CN114252192A

CN114252192A - Method and apparatus for diagnosing a force reaction sensor assembly

Info

Publication number: CN114252192A
Application number: CN202011003682.3A
Authority: CN
Inventors: 郭伦文; 刘延斌; 文杰; 付玲; 蒋凯歌
Original assignee: Zoomlion Heavy Industry Science and Technology Co Ltd
Current assignee: Zoomlion Heavy Industry Science and Technology Co Ltd
Priority date: 2020-09-22
Filing date: 2020-09-22
Publication date: 2022-03-29
Anticipated expiration: 2040-09-22
Also published as: CN114252192B

Abstract

The embodiment of the invention provides a method and a device for diagnosing a stressed sensor assembly, and belongs to the technical field of engineering machinery. The method comprises the following steps: calculating a first value of a reaction force according to the output voltage of the first bridge circuit, and calculating a second value of the reaction force according to the output voltage of the third bridge circuit; judging whether the difference between the first reaction force value and the second reaction force value is smaller than a difference threshold value; judging whether data jumping exists between the first counter force value and the second counter force value; and determining that the force sensor component has no fault when the difference between the first counter force value and the second counter force value is smaller than the difference threshold value and no data jump exists between the first counter force value and the second counter force value. Through mutual inspection and self-checking of the first counter force value and the second counter force value, whether a fault exists in the supporting leg counter force sensor assembly can be effectively judged, and therefore effectiveness of supporting leg counter force is guaranteed.

Description

Method and apparatus for diagnosing a force reaction sensor assembly

Technical Field

The invention relates to the technical field of engineering machinery, in particular to a method and a device for diagnosing a stressed sensor assembly.

Background

In mechanical structures, counter force measurements are often necessary. For example, in a construction machine, it is necessary to measure a leg reaction force.

In order to improve the anti-overturning capability of engineering machinery (such as an automobile crane, a pump truck, a fire truck and the like) during operation, a supporting leg supporting structure generally extends to the periphery, and the supporting force of the supporting structure directly reflects the current supporting safety condition of the engineering truck, for example: (1) when the counter force of any supporting leg is larger than the designed bearing limit of the supporting leg, the supporting leg has the risk of instability and failure, and the whole machine has the possibility of rollover accidents; (2) when the counter force of any supporting leg is close to the bearing capacity of the ground, the supporting ground has a collapse and settlement risk, and the engineering machinery can be tipped over; (3) when the counter force of any supporting leg is close to zero, the supporting leg is indicated to generate a 'virtual leg', and construction potential safety hazards exist; (4) more seriously, when the counter force of any two adjacent supporting legs is close to zero, the engineering machinery has serious risk of overturning and instability.

It is therefore necessary to use a detection device to detect the counter force. For the detection device, it is important to efficiently diagnose whether the device has a failure.

Disclosure of Invention

An object of the embodiments of the present invention is to provide a method and an apparatus for diagnosing a force sensor assembly, which can effectively diagnose whether a force sensor assembly has a fault.

In order to achieve the above object, an embodiment of the present invention provides a method for diagnosing a force-receiving sensor assembly, in which a first bridge circuit composed of a first set of strain gauges and a third bridge circuit composed of a third set of strain gauges are disposed, the method including: calculating a first value of a reaction force according to the output voltage of the first bridge circuit, and calculating a second value of the reaction force according to the output voltage of the third bridge circuit; judging whether the difference between the first reaction force value and the second reaction force value is smaller than a difference threshold value; judging whether data jumping exists between the first counter force value and the second counter force value; and determining that the force sensor component is not in fault when the difference between the first counter force value and the second counter force value is smaller than a difference threshold value and no data jump exists between the first counter force value and the second counter force value.

Optionally, the determining whether a difference between the first reaction force value and the second reaction force value is smaller than a difference threshold includes: determining that a difference between the first value of the reaction force and the second value of the reaction force is less than the difference threshold value when:

wherein, X₁(t) is a first value of the reaction force at the present time, X₂(t) is the second value of the reaction force at the current time, t is the current time, η_XA difference amount threshold.

Optionally, the determining whether there is a data transition between the first counter force value and the second counter force value includes: determining that there is no data transition in both the first value of the counter force and the second value of the counter force if the following condition is satisfied:

|X₁(t)-(2X₁(t-T)-X₁(t-2T))|＜a_X，

|X₂(t)-(2X₂(t-T)-X₂(t-2T))|＜a_X，

wherein, X₁(t) is a first value of the reaction force at the present time, X₂(t) is the second value of the reaction force at the current time, t is the current time, η_XA difference threshold, T is a sampling period, a_XTo measure the continuity threshold.

Optionally, the force sensor assembly is installed at a piston rod body of a vertical support cylinder of the engineering machinery support leg, and is used for measuring the counter force of the support leg, and the method further includes: determining a final leg reaction force according to the first reaction force value and the second reaction force value under the condition that the stress sensor assembly has no fault; acquiring current weight estimation of the whole vehicle and bending moment vector estimation based on the center position of a frame of the whole vehicle from torque limiter data of the engineering machinery; and determining the reliability of the measurement result of the stress sensor assembly according to the final support leg counter force of each support leg of the engineering machinery, the current weight estimation of the whole vehicle and the bending moment vector estimation based on the center position of the frame of the whole vehicle.

Optionally, determining the reliability of the measurement result of the force sensor assembly according to the final leg reaction force of each leg of the engineering machine, the current weight estimation of the whole vehicle, and the bending moment vector estimation based on the center position of the frame of the whole vehicle includes: determining that the measurement of the force sensor assembly has reliability if the following conditions are met:

and is

Wherein i is the number of the support legs, N is the number of the support legs, F_GiFor the final leg reaction force determined for the leg numbered i,

in order to estimate the current weight of the whole vehicle,

is the bending moment vector estimation based on the center position of the whole vehicle frame, delta_GEstimating an error threshold, δ, for a preset weight_MAn error threshold is estimated for a preset bending moment,

is a coordinate vector from the center of the whole vehicle frame to the supporting position of the corresponding supporting leg,

to aim at the braidThe final leg reaction force vector determined by the leg with the number i.

Optionally, the force sensor assembly includes: the upper surface of the bearing area is used for bearing the load applied by the structure to be tested; a fixed region for mechanical connection with a structure under test, wherein the fixed region is disposed around the load-bearing region; the strain sensitive area is positioned below the fixed area and is provided with a cavity; and a support region below the strain sensitive region for supporting.

Optionally, a second bridge circuit formed by a second group of strain gauges is further disposed in the force sensor assembly, two fixed resistors connected in series are connected in parallel in the second bridge circuit, and calculating a first counter force value according to the output voltage of the first bridge circuit and calculating a second counter force value according to the output voltage of the third bridge circuit includes: acquiring the output voltage of the first bridge circuit and the output voltage of the third bridge circuit; acquiring a first half-bridge voltage and a second half-bridge voltage which are respectively output by two half-bridges of the second bridge circuit; acquiring included angles between an X axis, a Y axis and a Z axis in a three-dimensional Cartesian coordinate system and the gravity direction respectively, wherein the Z axis in the three-dimensional Cartesian coordinate system is a central axis of the supporting leg reaction force sensor assembly, and the X axis points to the installation position of a strain gauge; calculating a first counter force value according to the output voltage of the first bridge circuit, the first half-bridge voltage, the second half-bridge voltage and the included angles of the X axis, the Y axis and the Z axis with the gravity direction respectively; and calculating the second counter force value according to the output voltage of the third bridge circuit, the first half-bridge voltage, the second half-bridge voltage and the included angles of the X axis, the Y axis and the Z axis with the gravity direction respectively.

Accordingly, an embodiment of the present invention further provides an apparatus for diagnosing a force-receiving sensor assembly, where a first bridge circuit including a first set of strain gauges and a third bridge circuit including a third set of strain gauges are disposed in the force-receiving sensor assembly, and the apparatus includes: the calculating module is used for calculating a first counter force value according to the output voltage of the first bridge circuit and a second counter force value according to the output voltage of the third bridge circuit; a first judgment module for judging whether the difference between the first counter force value and the second counter force value is smaller than a difference threshold; the second judging module is used for judging whether data jumping exists between the first counter force value and the second counter force value; and a first determination module configured to determine that the force sensor assembly is not faulty when a difference between the first reaction force value and the second reaction force value is smaller than a difference threshold and no data transition is present between the first reaction force value and the second reaction force value.

Optionally, the first determining module is configured to determine that a difference between the first reaction force value and the second reaction force value is smaller than the difference threshold when the following conditions are met:

Optionally, the second determining module is configured to determine that there is no data jump between the first counter force value and the second counter force value when the following conditions are met:

|X₁(t)-(2X₁(t-T)-X₁(t-2T))|＜a_X，

|X₂(t)-(2X₂(t-T)-X₂(t-2T))|＜a_X，

Optionally, the force sensor assembly is installed in the vertical support cylinder piston rod body of the engineering machinery landing leg for measuring the counterforce of the landing leg, the device further includes: a second determination module for determining a final leg reaction force according to the first reaction force value and the second reaction force value when the leg reaction force sensor assembly is not in failure; the acquisition module is used for acquiring the current weight estimation of the whole vehicle and the bending moment vector estimation based on the center position of the frame of the whole vehicle from the torque limiter data of the engineering machinery; and the third determining module is used for determining the reliability of the measuring result of the stress sensor assembly according to the final support leg counter force of each support leg of the engineering machinery, the current weight estimation of the whole vehicle and the bending moment vector estimation based on the center position of the frame of the whole vehicle.

Optionally, the third determining module is configured to determine that the measurement result of the force sensor assembly has reliability if the following condition is satisfied:

and is

Wherein i is the number of the support legs, N is the number of the support legs, F_GiThe resulting leg reaction force for the leg numbered i,

in order to estimate the current weight of the whole vehicle,

is a coordinate vector from the center of the whole vehicle frame to the supporting position of the supporting leg with the number i,

the final leg reaction force vector of the leg numbered i.

Optionally, the leg reaction force sensor assembly includes: the upper surface of the bearing area is used for bearing the load applied by the structure to be tested; a fixed region for mechanical connection with a structure under test, wherein the fixed region is disposed around the load-bearing region; the strain sensitive area is positioned below the fixed area and is provided with a cavity; and a support region below the strain sensitive region for supporting.

Optionally, a second bridge circuit formed by a second group of strain gauges is further disposed in the force sensor assembly, two fixed resistors connected in series are connected in parallel in the second bridge circuit, and the calculation module includes: a first obtaining unit, configured to obtain an output voltage of the first bridge circuit and an output voltage of the third bridge circuit; a second obtaining unit, configured to obtain a first half-bridge voltage and a second half-bridge voltage output by each of two half-bridges of the second bridge circuit; the third acquisition unit is used for acquiring included angles between an X axis, a Y axis and a Z axis in a three-dimensional Cartesian coordinate system and the gravity direction respectively, wherein the Z axis in the three-dimensional Cartesian coordinate system is a central axis of the supporting leg reaction force sensor assembly, and the X axis points to the installation position of a strain gauge; a computing unit to: calculating a first counter force value according to the output voltage of the first bridge circuit, the first half-bridge voltage, the second half-bridge voltage and the included angles of the X axis, the Y axis and the Z axis with the gravity direction respectively; and calculating the second counter force value according to the output voltage of the third bridge circuit, the first half-bridge voltage, the second half-bridge voltage and the included angles of the X axis, the Y axis and the Z axis with the gravity direction respectively.

Accordingly, embodiments of the present invention also provide a machine-readable storage medium having stored thereon instructions for causing a machine to perform the above-described method of diagnosing a force sensor assembly.

Through the technical scheme, the self-checking of the first counter force value and the second counter force value can be realized by judging whether the difference between the first counter force value and the second counter force value is smaller than the difference threshold value or not, judging whether data jumping exists between the first counter force value and the second counter force value or not, and realizing the self-checking of the first counter force value and the second counter force value. Through mutual inspection and self-checking, whether the stress sensor assembly has a fault can be effectively judged, and therefore effectiveness of counter force measurement is guaranteed.

Additional features and advantages of embodiments of the invention will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the embodiments of the invention without limiting the embodiments of the invention. In the drawings:

FIG. 1 illustrates a schematic view of the installation of a force sensor assembly as a leg reaction sensor assembly according to an embodiment of the invention;

FIG. 2 illustrates a schematic diagram showing the structure and installation of a force-bearing sensor assembly as a leg reaction force sensor assembly according to an embodiment of the invention;

fig. 3(a) shows a plan view of the leg reaction force sensor assembly shown in fig. 2, and fig. 3(b) shows a perspective view of the leg reaction force sensor assembly shown in fig. 2;

FIG. 4 shows a cross-sectional view of the leg reaction force sensor assembly shown in FIG. 2;

FIG. 5 illustrates the blocking effect of the annular groove on the distributed transmission of the foot support plate contact force;

FIG. 6 shows a dimensional schematic of the annular groove;

FIG. 7 shows a schematic diagram of a bridge circuit formed by strain gauges;

FIG. 8 shows a leg reaction load path transfer diagram;

FIG. 9 is a schematic diagram illustrating the construction and installation of a force sensor assembly as a leg reaction force sensor assembly according to one embodiment of the invention;

FIGS. 10(a) to 10(c) show a top view, a side view, and a perspective view, respectively, of the force sensor assembly shown in FIG. 9 as a leg reaction force sensor assembly;

FIG. 11 shows a cross-sectional view of the leg reaction force sensor assembly shown in FIG. 9;

FIG. 12 shows a schematic inclination of the leg reaction force sensor assembly;

FIG. 13 is a block diagram showing the structure of a reaction force measuring device according to an embodiment of the invention;

FIG. 14 shows a schematic diagram of a second bridge circuit;

FIG. 15 shows a schematic diagram of a first bridge circuit;

FIG. 16 shows a schematic view of the angle between the first and second sets of strain gages;

FIG. 17 is a schematic diagram showing some of the parameters involved in the counter force measurement method in the case of a force applied to the force sensor assembly when tilted;

FIG. 18 shows a flow diagram of a method of counter force measurement according to an embodiment of the invention;

FIG. 19 shows a flow diagram of a counter force measurement method according to another embodiment of the invention;

FIG. 20 shows a schematic flow diagram of a method of diagnosing a leg reaction force sensor assembly according to an embodiment of the invention;

FIG. 21 shows a block diagram of a system for diagnosing a leg reaction force sensor assembly according to an embodiment of the invention; and

fig. 22 is a block diagram showing the structure of an apparatus for diagnosing a leg reaction force sensor assembly according to an embodiment of the present invention.

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating embodiments of the invention, are given by way of illustration and explanation only, not limitation.

It should be noted that, the orientation relationship described in the embodiments of the present invention is described by taking the case where the force sensor assembly is vertically placed (the bearing area is above and the supporting area is below), and in the case where the placing direction of the force sensor assembly is changed, the orientation relationship may also be changed correspondingly. The terms "surround", "annular" and the like mean a closed ring formed in various shapes such as a square, a circle and the like. In addition, the force sensor assembly provided by the invention can be used for detecting transverse force besides vertical force.

An embodiment of the present invention provides a force sensor assembly, which may include: the upper surface of the bearing area is used for bearing the load applied by the structure to be tested; a fixed region for mechanical connection with a structure under test, wherein the fixed region is disposed around the load-bearing region; the strain sensitive area is positioned below the fixed area, and one or more groups of strain gauges are arranged on the inner wall of the cavity of the strain sensitive area, wherein each group of strain gauges form a bridge circuit; and a support region below the strain sensitive region for supporting.

The load bearing zone, anchor zone, strain sensitive zone, support zone may each be a separate component, or preferably the load bearing zone, anchor zone, strain sensitive zone, support zone may be integrally formed.

The support region may be provided with an annular groove. The annular groove can block the dispersion of a force transmission path of the sensor assembly, so that the strain of the strain sensitive area is insensitive to the contact force distribution change at the bottom of the supporting area, and the measurement precision is improved. The annular groove is arranged, so that when the force sensor assembly provided by the invention is used as a reaction sensor assembly to measure reaction force, the influence of the distribution change of the reaction contact surface on measurement can be reduced, and the measurement accuracy of the reaction force is improved.

The strain sensitive region may be any suitable structure provided with a cavity, and may be, for example, a cylindrical strain sensitive region, preferably a cylindrical strain sensitive region, but is not limited thereto, and may also be, for example, a square cylindrical strain sensitive region or other types of strain sensitive regions.

The support area is preferably of the ball head type. Under the condition that the supporting area is the supporting area, a bottom foot supporting plate can be further arranged, and the supporting area of the ball head type and the bottom foot supporting plate can be in contact connection through a ball head and ball socket pair, so that the supporting effect is achieved. The support areas may also be of a cuboid shape, in which case the footing support plates may not be provided.

The inner side section of the annular groove is in a circular arc shape or other transitional circular arc shapes. The annular groove may be provided in the lower half of the support region. The groove ring of the annular groove can be in a shape of equal height or in a shape of unequal height. The groove height (or average height) is too small to easily form stress concentration on the inner side, the height is too large to reduce the structural strength, and there is a safety risk, and a suitable groove height is 1/10 to 1/2 of the diameter of the support region. Similarly, the annular groove has a neck diameter that is too large and the contact force breaking effect is insignificant, and too small, affecting structural strength, so suitable neck diameters are 1/5 to 9/10 of the diameter of the support zone. In the case of a support zone of the ball-head type, the diameter of the support zone is the diameter of the ball-head type. In the case of a support zone of the cuboid type, the diameter of the support zone is the cuboid transverse width.

The opening of the annular groove may preferably face horizontally to the outside, but the embodiment of the present invention is not limited thereto, and the opening direction of the annular groove may be set to be arbitrary, and the opening direction may face a direction at an arbitrary angle with the horizontal direction, for example, the opening direction may be obliquely upward or obliquely downward. The provision of a horizontally outwardly facing annular groove opening is more advantageous to machine than annular grooves in other directions and such an arrangement minimizes material removal and structural load bearing losses.

The fixation region may mechanically connect the force sensor assembly to the structure under test via a transition piece structure, and the fixation region may mechanically connect to the transition piece structure via a fastener. The fasteners may be, for example, bolts or the like. In an alternative, the fastening region may also be fastened to the transition piece structure by welding. Additionally, it will be appreciated that the use of a transition piece structure may not be required if the structure being measured matches the structure of the force sensor assembly. The fixed area is directly connected with the tested structure mechanically.

The bearing area can be arranged as a stop table, and the stop table has the advantages of resisting horizontal lateral force and avoiding the sliding dislocation of the bearing area. The stop land may be a stop boss or a stop recess land. It will be appreciated that the location of the load bearing zone is not limited to a stop and may be other types of load bearing zones, for example, the middle of the load bearing zone may not have a cavity as the stop.

The stop abutment may preferably be a stop boss, since the upper surface of the stop boss is located at a greater distance from the strain gauge on which the strain sensitive area is located, thus providing greater measurement accuracy. The stop boss may be annular and the wall thickness of the stop boss may be arranged to be greater than the wall thickness of the strain sensitive region. The transition between the stop lug and the strain sensitive region may have a thickness variation such that the wall thickness of the stop lug is greater than the wall thickness of the barrel-type strain sensitive region. This may be advantageous to reduce the strain effect of the detent boss contact force distribution on the barrel strain sensitive area. This is because the contact surface of the stopper boss is increased, so that the contact stress is reduced; and the thickness of the opening of the stop boss is increased, the structural rigidity is increased, and the contact stress distribution is not easily influenced by deformation. The beneficial effect who sets up like this is that the distribution of strain of barrel-type strain sensitive area is very even, is favorable to eliminating the precision influence that foil gage process error brought for measurement accuracy is very high.

In order to form the strain sensitive region required by the strain gauge, while making the stress distribution of the sensing region more uniform, and considering the structural strength safety, the wall thickness of the strain sensitive region is preferably reduced to 50% to 95% of the wall thickness of the stop boss.

The fixation section and transition piece structure may be configured to be a tight fit or a clearance fit, preferably both. In the loading process of the stress sensor assembly, the upper surface of the bearing area in the normal load transfer relation is a load bearing surface, however, the stress sensor assembly body can generate tiny compression elastic deformation, and the fixed area partially bears partial load. In order to keep only the bearing region carrying the load and to avoid that the fixing region carries the load partially, at least a part of the upper surface of the fixing region may be arranged to be clearance-fitted with the transition piece structure, i.e. at least a part of the gap may be arranged between the fixing region and the connection face of the transition piece structure. For example, it may be particularly provided that a portion of the upper surface of the fixing zone is in close contact with the transition piece structure and another portion is in clearance fit with the transition piece structure. For example, one half of the upper surface of the fixation section may be provided in intimate contact with the transition piece structure and the other half of the upper surface may be provided in clearance fit with the transition piece structure. Alternatively, the upper surfaces of the fixation areas may all be provided in clearance fit with the transition piece structure.

A suitable gap size u (also referred to as height) is required to prevent the portion of the clearance fit from taking part of the load due to the compressive elastic deformation. The size u (which may be referred to as height) of the gap is set to satisfy the requirement of equation 1 below:

wherein, F_mFor the rated load of the landing leg, a is the area of the upper surface of the movable boss (i.e., the area of the load acting surface), h is the height of the boss, E is the material elastic modulus of the landing leg reaction force sensor assembly, and k is a safety coefficient and is a known value.

The size u of the gap must have sufficient redundancy design in consideration of machining errors, but the excessive gap brings requirements on sealing, safety, protection and the like, so the comprehensive consideration of the surface gap u is preferably in the range of 0.1mm to 1.0 mm. It should be noted that the size of the gap according to the embodiment of the present invention refers to the size of the gap when the force sensor assembly is not loaded.

The gap may be filled with a sealant, which will not be described herein. May be used to seal dust or the like from outside the sensor assembly. The sealant is preferably a soft sealant, such as a weatherable soft sealant. Because the elastic modulus difference of the metal and the soft sealant is very large, the force transmitted by the sealant can be ignored, and the detection precision is not influenced.

The stress sensor assembly provided by the embodiment of the invention has the following advantages:

(1) the annular groove is formed in the supporting area, so that the force transmission path of the sensor assembly can be blocked from being dispersed, the strain of the strain sensitive area is insensitive to the contact force distribution change at the bottom of the supporting area, and the measurement precision is improved;

(2) the device can be mechanically connected with a structure to be detected, and can be matched with a strain gauge arranged in a cavity of a strain sensitive area, so that the device can monitor stress in real time;

(3) the method has the advantages of high reliability, high comprehensive precision, good dynamic measurement performance, low delay and the like, can ensure the bearing safety and the protective performance, and has small change on the whole engineering machine and convenient maintenance and replacement when being applied to the engineering machine.

The force sensor assembly provided by the invention can be used for measuring the counter force of any structure to be measured, or can be used for measuring horizontal side force and the like (in the case that the force sensor assembly is inclined). Alternatively, the force sensor assembly may be used as a leg reaction force sensor assembly to measure leg reaction forces.

In the related art, a method for detecting the magnitude of the counterforce of the support leg by the engineering machine is generally realized by detecting the oil pressure of the support leg oil cylinder, but the method has the following defects: (1) an oil pressure sensor needs to be arranged in the oil cylinder for detecting the oil pressure, so that the risk of oil leakage is increased; (2) due to the factors of friction, lateral load, pressure abandoning and the like, the oil pressure thrust and the supporting force are possibly greatly different, so that the measurement precision is very low, and the maximum error is more than 15%; (3) the oil pressure measurement mode is that the landing leg load is transmitted to the pressure sensor through hydraulic oil, is an indirect measurement of the reaction force, has serious hysteresis of signal, and the maximum hysteresis is more than 5 s. The stress sensor assembly provided by the invention is used as a support leg reaction force sensor assembly to measure the support leg reaction force, so that the defects can be avoided.

When the sensor assembly is applied as a supporting leg reaction force sensor assembly, the fixed area can be mechanically connected with a vertical oil cylinder piston rod body of a supporting leg through a transition connecting piece structure, wherein the transition connecting piece structure is fixed at the vertical supporting oil cylinder piston rod body of the supporting leg.

Next, the force receiving sensor assembly of the present invention will be exemplified as a leg reaction force sensor assembly by way of example. In each embodiment, the bearing region is a movable boss, the strain sensitive region is a cylindrical strain sensitive region, and the support region is a ball-head support region, i.e., the force sensor assembly is exemplified by using the preferred embodiment of the bearing region, the strain sensitive region, and the support region. It will be appreciated that in other embodiments, the implementation of the load bearing, strain sensitive, and support regions may be a combination of any of these alternative implementations. In the embodiments described below, the force sensor assembly is also referred to as a leg reaction force sensor assembly.

Fig. 1 shows a schematic view of the installation of a force-receiving sensor assembly as a leg reaction force sensor assembly according to an embodiment of the present invention. As shown in fig. 1, the leg reaction force sensor assembly 3 can be mechanically connected to the piston rod body of the vertical support cylinder 2 of the leg and installed below the leg beam of the construction machine. The leg reaction force signals detected by the leg reaction force sensor assembly 3 can be transmitted to the main controller by wire (e.g. by cable) or wirelessly (e.g. by radio), and the main controller derives further operation instructions by integrating the leg reaction force signals of a plurality of legs, or calculates required information such as the total weight, the position of the center of gravity, the safety state, etc.

Fig. 2 to 4 show a first embodiment of a leg reaction force sensor assembly according to an embodiment of the present invention. As shown in fig. 2, the leg reaction force sensor assembly 3.2b may be mechanically connected to the vertical support cylinder piston rod body 2.1 (a portion of which is shown in fig. 2) of the leg by a transition piece structure 3.1 b. The transition piece structure 3.1b may be integrally connected to the vertical support cylinder ram body 2.1, for example, by a filler weld process, the weld location being shown as b-1. The transition piece structure 3.1b may be cylindrical to match the shape of the vertical support cylinder ram body 2.1, and the overall width of the transition piece structure 3.1b may be slightly greater than the diameter of the vertical support cylinder ram body 2.1 or both may be substantially the same. The bottom of the transition piece structure 3.1a may be hollowed out in a portion, and the diameter of the hollowed out portion may be the same as the diameter of the stop boss, respectively, to accommodate the stop boss.

The fixing area of the leg reaction sensor assembly may be arranged as a ring, the diameter of which may be substantially the same as the diameter of the transition piece structure 3.1b, in the alternative, the fixing area may also be arranged as a square, etc. In this embodiment, the fixed area is an annular area, and the fixed area is referred to as an annular area in the detailed description. The annular region may be mechanically connected to the transition piece structure 3.1b by fasteners. The fastener may be, for example, bolt b-2. As shown in fig. 3(a) to 3(b), the annular region may be provided with a plurality of bolt holes, which may be evenly distributed. The transition piece structure 3.1b is provided with the same number of bolt holes to achieve a mechanical connection of the two by means of bolts b-2.

The annular region upper surface b-3 is clearance fit with the transition piece structure 3.1b, preferably in the range of 0.1mm to 1.0mm, or may be determined according to equation (1). The gap may be filled with, for example, a weather resistant soft sealant.

The upper surface b-4 of the stop boss is in intimate contact with the transition piece structure 3.1 b. The upper surface b-4 of the stop boss can bear the load of the support leg during operation. The stop boss may be an annular stop boss.

The structure of the support region may be a portion of a spherical structure or substantially the entire spherical structure. As shown in fig. 2, the overall width of the support region may be greater than that of the cylinder-type strain sensitive region and less than that of the annular region. The support area can be in contact connection with the foot support plate 4b through a ball-and-socket friction pair b-5. The surface portion of the support area in contact with the foot support plate 4b is arcuate. When the supporting leg is retracted, the supporting base of the foot can be hung at the contraction part of the supporting leg reaction force sensor assembly through structures such as an upper cover plate or a locking pin.

As shown in fig. 4, in this embodiment, the leg reaction force sensor assembly includes: a stop boss 3.2b-1, an annular zone 3.2b-2, the annular zone comprising a plurality of bolt holes, a cylindrical strain sensitive zone 3.2b-3 and a support zone 3.2 b-4. N1 in fig. 4 represents the applied load (i.e., the load carried by the upper surface of the stopper boss), and the broken line represents the load path in the leg reaction force sensor assembly, and F represents the resultant contact load force. The counterforce of the support leg is the vertical component of the resultant force of the contact load. A schematic diagram of the positive pressure force of the leg reaction force sensor assembly is shown in fig. 4. The stop boss 3.2b-1, the annular zone 3.2b-2, the barrel-type strain sensitive zone 3.2b-3 and the support zone 3.2b-4 may be integrally formed.

The wall thickness of the stop boss 3.2b-1 may be set larger than the wall thickness of the barrel-type strain sensitive area 3.2 b-3. The stop boss 3.2b-1 may have a thickness variation at the transition 3.2b-6 to the barrel-type strain sensitive area 3.2b-3 such that the wall thickness of the stop boss 3.2b-1 is greater than the wall thickness of the barrel-type strain sensitive area 3.2 b-3. This may be advantageous to reduce the strain effect of the detent boss contact force distribution on the barrel strain sensitive area. This is because the contact surface of the stopper boss is increased, so that the contact stress is reduced; and the thickness of the opening of the stop boss is increased, the structural rigidity is increased, and the contact stress distribution is not easily influenced by deformation. The beneficial effect who sets up like this is that the distribution of strain of barrel-type strain sensitive area is very even, is favorable to eliminating the precision influence that foil gage process error brought for measurement accuracy is very high.

In order to form the strain sensitive region required for the strain gauge, while making the stress distribution of the sensing region more uniform, and considering the structural strength safety, the wall thickness of the barrel-type strain sensitive region is preferably reduced to 50% to 95% of the wall thickness of the stopper boss.

The embodiment of the invention also has certain limitation on the bolt pretightening force used for mechanical connection with the transition connecting piece structure. As can be seen from the load path shown by the dotted line in fig. 4, the bolt pretightening force transmission path does not pass through the cylindrical strain sensitive area and is far away from the installation position of the strain patch, so that the influence on the measurement result of the support leg reaction force sensor assembly is small. However, when the pretightening force of the bolt is too large, the cylindrical structure can be radially deformed, and the transverse strain can be deviated. Therefore, when the supporting leg reaction force sensor assembly is used, the pretightening force of the bolt needs to be adjusted within a reasonable range, and the stability of initial output is ensured. Preferably, the bolt pretension force is reasonably in the range of 10 N.m to 80 N.m.

The support areas 3.2b-4 may be provided with annular grooves 3.2b-7 which may reduce the strain effect of variations in the contact force distribution of the support areas on the cartridge type strain sensitive areas. As can be seen from the load transmission path shown by the dotted line in fig. 4, the load is concentrated at the bottom portion of the foot supporting plate, thereby blocking the dispersed transmission of the contact force of the foot supporting plate, so that the cylinder type strain sensitive region strain is insensitive to the variation of the contact force distribution. The blocking effect of the annular groove is shown in fig. 5. The transmission path of the leg reaction force in the leg reaction force sensor assembly is shown by the dark area in the figure.

As shown in fig. 6, the inside cross-section of the annular groove is in the shape of a circular arc or other transitional circular arc. The annular groove may be provided in the lower half of the support region. The groove ring of the annular groove may be of the same height as shown or of different heights. The groove height is too small, stress concentration on the inner side is easy to form, the height is too large, the structural strength can be reduced, and safety risk exists, and a proper groove height dimension H is 1/10D-1/2D, wherein D is the diameter of the supporting area. Similarly, the necking diameter of the annular groove is too large, the contact force breaking effect is insignificant, and the necking diameter is too small, affecting the structural strength, so that suitable necking diameters D are 1/5D to 9/10D, where D is the diameter of the support zone.

The design of the annular groove has the beneficial effects that when a large load is applied, the contact relation is severe, or the offset load is applied, the annular groove enables the strain of the cylindrical strain sensitive area to be insensitive to the contact force distribution change of the bottom of the ball head, so that high measurement precision is formed.

One or more groups of strain gauges 3.2b-5 can be stuck to the appropriate height position of the inner wall of the cavity of the cylinder type strain sensitive area 3.2b-3, and each group of strain gauges can comprise 4 strain gauge pairs which are annularly and symmetrically arranged. The strain gage pair may include transversely and longitudinally arranged strain gages arranged in the same position to form a T-shape or an inverted T-shape. Each set of strain gages may form a bridge circuit. The proper height is the place where the strain of the stress analysis is more uniform. In any embodiment of the present invention, it is only preferable that the strain gauge pairs are arranged in a T shape or an inverted T shape, and optionally, the strain gauge pairs may be arranged in an L shape or an inverted L shape, or any other shape.

Fig. 7 shows a schematic diagram of a bridge circuit formed by strain gauges. In fig. 7, Rv1 and Rh1, Rv2 and Rh2 … … are strain gauge pairs, respectively, where Rv1, Rv2 … … denote vertically arranged strain gauges, and Rh1, Rh2 … … denote laterally arranged strain gauges. Ui is the input voltage of the bridge circuit, and Uo is the output voltage. The side of the annular area can be provided with a cable hole, and a cable connected with the output of the bridge circuit extends out of the supporting leg reaction force sensor assembly through the cable hole. The output of the bridge circuit may also be transmitted wirelessly.

In this embodiment, one set of strain gauges is only used for example, and multiple sets of strain gauges may be disposed in the cavity of the barrel-type strain sensitive area. Different strain gauge groups can be arranged at different heights or the same height, and each strain gauge pair of the same strain gauge group is arranged at the same height.

Fig. 8 shows a leg reaction force load path transfer diagram. As shown in fig. 8, the leg reaction force load path is: the ground is greater than a footing support plate, a landing leg counter-force sensor component, a vertical oil cylinder, a combined landing leg beam and an engineering machine frame, wherein the ground is in contact with the footing support plate, the footing support plate is in contact connection with the landing leg counter-force sensor component through a ball head and ball socket pair, the landing leg counter-force sensor component is welded with the vertical oil cylinder through a transition connecting piece structure, the vertical oil cylinder is mechanically connected with the combined landing leg beam, and the combined landing leg beam and the engineering machine frame are stressed through a sliding block. Landing leg reaction force sensor subassembly direct embedding is in landing leg reaction force transmission route, therefore does not have other transmission routes to share the landing leg reaction and leads to landing leg reaction force sensor subassembly to measure the deviation, and the dynamometry direction of landing leg reaction force sensor subassembly is the vertical atress direction of perpendicular hydro-cylinder to structure itself is movable bulb structure, can effectively reduce the influence of side load to measurement accuracy.

A second embodiment of the leg reaction force sensor assembly according to the embodiment of the present invention is shown in fig. 9 to 11. As shown in fig. 9, the leg reaction force sensor assembly 3.2a may be mechanically connected to the vertical support cylinder piston rod body 2.1 (a portion of which is shown in fig. 2) of the leg by a transition piece structure 3.1 a. The transition piece structure 3.1a may be integrally connected to the vertical support cylinder ram body 2.1, for example, by a filler weld process, the weld location being shown as a-1. The transition piece formation 3.1a may be cylindrical to match the shape of the vertical support cylinder ram body 2.1 and may be substantially the same diameter. The bottom of the transition piece structure 3.1a may be hollowed out in a portion, and the diameter of the hollowed out portion may be the same as the diameter of the stop boss, respectively, to accommodate the stop boss.

The fixing area of the leg reaction sensor assembly may be arranged as a ring, the diameter of which may be substantially the same as the diameter of the transition piece structure 3.1a, in the alternative, the fixing area may also be arranged as a square, etc. In this embodiment, the fixed area is an annular area, and the fixed area is referred to as an annular area in the detailed description. The annular region may be mechanically connected to the transition piece structure 3.1a by fasteners. The fastener may be, for example, bolt a-2. As shown in fig. 10(a) to 10(c), the annular region may be provided with a plurality of bolt holes, which may be evenly distributed. The transition piece structure 3.1a is provided with the same number of bolt holes to achieve a mechanical connection of the two by means of bolts a-2.

One part of the upper surface of the annular region is in close contact with the transition piece structure 3.1a, and the other part a-3 is in clearance fit with the transition piece structure 3.1a, and the clearance can be filled with a weather-resistant soft sealant for example. For example, one half of the upper surface of the annular region may be provided in intimate contact with the transition piece structure 3.1a and the other half of the upper surface may be provided in clearance fit with the transition piece structure 3.1 a.

The upper surface a-4 of the stop boss is in intimate contact with the transition piece structure 3.1 a. The upper surface a-4 of the stop boss can bear the load of the support leg during operation. The stop boss may be an annular stop boss. In this embodiment, the stop boss, the annular region and the barrel-type strain sensitive region have cavities of substantially the same diameter. The diameter of the cavity of the cylinder type strain sensitive area can also be larger than the diameter of the cavity of the stop boss and the annular area, so that a better strain sensitive effect can be formed in the cylinder type strain sensitive area.

The structure of the support region may be a portion of a spherical structure or substantially the entire spherical structure. As shown in fig. 3(b), the overall width of the support region may be greater than that of the cylinder-type strain sensitive region and less than that of the annular region. The support area can be in contact connection with the foot support plate 4a via a ball-and-socket friction pair a-5. The surface portion of the support area in contact with the foot support plate 4a is arcuate. When the supporting leg is retracted, the supporting base of the foot can be hung at the contraction part of the supporting leg reaction force sensor assembly through structures such as an upper cover plate or a locking pin.

As shown in fig. 4, in this embodiment, the leg reaction force sensor assembly includes: a stop boss 3.2a-1, an annular zone 3.2a-2 containing a plurality of bolt holes, a cylindrical strain sensitive zone 3.2a-3 and a support zone 3.2 a-4. N1 in fig. 4 represents the applied load (i.e., the load carried by the upper surface of the stopper boss), and the broken line represents the load path in the leg reaction force sensor assembly, and F represents the resultant contact load force. The counterforce of the support leg is the vertical component of the resultant force of the contact load. A schematic diagram of the positive pressure force of the leg reaction force sensor assembly is shown in fig. 4. The stop boss 3.2a-1, the annular zone 3.2a-2, the barrel-type strain sensitive zone 3.2a-3 and the support zone 3.2a-4 may be integrally formed. The landing leg reaction force sensor assembly provided by the embodiment has the advantages of simple and compact structure, high reliability, high unbalance loading resistance, high safety and the like.

The wall thickness of the stop boss 3.2a-1 may be set substantially equal to the wall thickness of the barrel-type strain sensitive area 3.2 a-3. Alternatively, the wall thickness of the stop boss 3.2a-1 may be made greater than the wall thickness of the barrel-type strain sensitive area 3.2a-3, similar to the first embodiment, to reduce the effect of the stop boss contact force distribution on the barrel-type strain sensitive area strain.

One or more groups of strain gauges 3.2a-5 can be stuck on the inner wall of the cavity of the cylinder type strain sensitive area 3.2a-3 at proper height, and each group of strain gauges can comprise 4 strain gauge pairs which are annularly and symmetrically arranged. The strain gage pair may include transversely and longitudinally arranged strain gages arranged in the same position to form a T-shape or an inverted T-shape. Each set of strain gages may form a bridge circuit. The proper height is the place where the strain of the stress analysis is more uniform. In any embodiment of the present invention, it is only preferable that the strain gauge pairs are arranged in a T shape or an inverted T shape, and optionally, the strain gauge pairs may be arranged in an L shape or an inverted L shape, or any other shape.

In this embodiment, the bridge circuit formed by the strain gauge is the same as the bridge circuit shown in fig. 7, and will not be described again here. In addition, similarly, multiple groups of strain gauges can be arranged in the cavity of the cylinder type strain sensitive area. Different strain gauge groups can be arranged at different heights or the same height, and each strain gauge pair of the same strain gauge group is arranged at the same height.

In this embodiment, the limitation of the size of the gap in the clearance fit, the limitation of the bolt pretightening force, the transmission of the counterforce load path of the leg, and the like are the same as those of the first embodiment of the leg counterforce sensor assembly provided by the embodiment of the present invention, and will not be described again here.

When the stress sensor assembly provided by the embodiment of the invention is used as a supporting leg reaction force sensor assembly, the following advantages are achieved:

(1) the device is less influenced by installation and is insensitive to a contact boundary, particularly, the arranged annular groove can block the force transmission path dispersion of the sensor assembly, so that the strain of the cylindrical strain sensitive area is insensitive to the contact force distribution change at the bottom of the supporting area, the influence of the distribution change of the counterforce contact surface of the supporting leg on measurement is reduced, and the measurement precision is improved.

(2) When the supporting legs deflect, the connecting bolt is enabled to be hardly subjected to shearing force due to the design of the stop boss, the deflecting load is borne by the contact force of the front face and the side face of the boss, the fracture risk of the bolt is reduced, and the anti-deflecting load safety is high.

(3) The transition connecting piece structure and the oil cylinder piston rod body are welded into a whole, the supporting leg reaction force sensor assembly is disassembled and assembled only by fastening or loosening the connecting bolt, and the initial output (zero deviation) is insensitive to the variation of the pretightening force of the bolt because the bolt installation position is not between the supporting leg reaction force action position and the strain measurement area, so that the installation and the maintenance are convenient.

(4) On the other hand, the strategy of the annular groove in the supporting zone can reduce errors caused by uncertainty of contact points in the supporting zone structurally, and improves the measurement accuracy of counter force of the supporting leg under the conditions of lateral loads such as deformation of the supporting leg, inclination of a supporting plate of the bottom leg, oblique-pulling and oblique-hanging and the like.

Next, a counter force measuring method and device will be described, which can be any type of counter force, such as a leg counter force or other similar counter forces. The method and apparatus are applicable to any force sensor assembly described in any embodiment of the present invention, or any other sensor assembly that detects a counter force using a bridge circuit formed by strain gauges disposed in a strain sensitive region. The force sensor assembly according to any of the embodiments of the present invention is mainly described as an example.

The counter-force measuring precision of the stressed sensor assembly is related to structural factors of the elastic body of the sensor, and is also related to using environment factors such as assembling conditions, stress conditions, using conditions and the like. In practical applications, the structure to be measured (e.g., a leg structure) may deflect and deform under load in relation to the position of the center of gravity, the total weight, and the ground conditions, which may cause the force sensor assembly to tilt and to receive lateral forces. As shown in fig. 12, the stop boss is subjected to an axial load N1 and a side load N2, where F represents the resultant contact load. In some cases, the foot support plate tilting may also cause the force sensor assembly to experience lateral forces. This will result in a deviation of the measured value of the counter force measured using conventional methods from the actual vertical counter force. When the stress sensor assembly is used, the contact part of the support area and the bottom supporting plate is fully lubricated, and under the condition that the support area is a ball head type support area, the tangential friction force of a ball head contact surface can be ignored, and then the contact force of the ball head type support area can be along the negative normal direction of the bottom surface of the ball head type support area.

In order to solve the technical problem, an aspect of the embodiments of the present invention provides a reaction force measuring device, as shown in fig. 13, where the reaction force measuring device may include: an included angle measuring module 1310, configured to obtain an included angle between a resultant force of a contact load borne by the force sensor assembly and the central axis, and obtain an included angle between a plane formed by the resultant force of the contact load and the central axis and a plane formed by the central axis and an installation position of a strain gauge in a strain sensitive area of the force sensor assembly; an inclination angle detecting device 1320, configured to detect inclination angles of an X axis, a Y axis, and a Z axis in a three-dimensional cartesian coordinate system with a gravity direction, respectively, where the Z axis in the three-dimensional cartesian coordinate system is a central axis of the force sensor assembly, and the X axis points to an installation position of the strain gauge; and a controller 1330, configured to obtain the counter force borne by the force sensor assembly according to an angle between the resultant force of the contact loads, an angle between the resultant force of the contact loads and the central axis, an angle between a plane formed by the resultant force of the contact loads and the central axis and a plane formed by the central axis and an installation position of a strain gauge, and angles between an X axis, a Y axis, and a Z axis in the three-dimensional cartesian coordinate system and the gravity direction, respectively.

The tilt angle detection device 1320 may be a tilt angle sensor or an acceleration sensor, which may be disposed at the bottom of the strain sensitive area (e.g., the bottom of the cavity of the barrel-type strain sensitive area), preferably fixed at the center of the bottom, especially at the very center. The tilt sensor may be any suitable sensor, such as a MEMS tilt sensor. In a three-dimensional cartesian coordinate system of the inclination angle detection device, a Z axis is a central axis of the force sensor assembly, an X axis points to an installation position of a strain gauge (which may be any one of the two sets of strain gauges), and a Y axis is correspondingly determined after the X axis is determined. The inclination angle detection device can detect the included angles gamma between the X axis, the Y axis and the Z axis and the gravity direction respectively_x,γ_y,γ_z。

The angle measurement module 1310 is located on the inner wall of the cavity of the strain sensitive region, and may include 4 pairs of strain gauges arranged circumferentially and symmetrically at a second height of the strain sensitive region of the force sensor assembly. Each of the strain gage pairs includes a transversely disposed strain gage and a longitudinally disposed strain gage, thereby being configured to be mounted in a T-shape or an inverted T-shape.

Optionally, the angle measurement module 1310 may be a second bridge circuit. Fig. 14 shows a schematic diagram of a second bridge circuit. As shown in fig. 14, the 4 strain pairs are a first strain gauge pair composed of rz1 and Rcc1, a second strain gauge pair composed of rz2 and Rcc2, a third strain gauge pair composed of rz3 and Rcc3, and a fourth strain gauge pair composed of rz4 and Rcc4, wherein the first strain gauge pair and the third strain gauge pair are symmetrically arranged, and the second strain gauge pair and the fourth strain gauge pair are symmetrically arranged. Each strain gage pair is configured to be mounted in a T-shape or an inverted T-shape, wherein longitudinal strain gages are respectively designated as rz1, rz2, rz3, rz4, and transverse strain gages are respectively designated as Rcc1, Rcc2, Rcc3, Rcc4, in the counterclockwise direction from the X-axis. The strain gauges Rzz1 and Rzz3 are connected in series to form a first arm of the second bridge circuit, the strain gauges Rzz1 and Rcc3 are connected in series to form a second arm of the second bridge circuit, the strain gauges Rcc2 and Rzz4 are connected in series to form a third arm of the second bridge circuit, and the strain gauges Rzz2 and Rcc4 are connected in series to form a fourth arm of the second bridge circuit. The first and second arms constitute a first half-bridge of the second bridge circuit, and the third and fourth arms constitute a second half-bridge of the second bridge circuit.

One or more pairs of fixed resistors connected in series are also connected in parallel in the second bridge circuit. As shown in fig. 14, a pair of fixed resistors R connected in series may be connected in parallel in the second bridge circuit. When the second bridge circuit is used, the half-bridge output voltage U of the second bridge circuit needs to be measured_x1And U_x2Wherein the input voltage U of the second bridge circuit_iKnown in advance. The second bridge circuit formed by the second group of strain gauges is an improved bridge circuit.

Alternatively, the angle measurement module 1310 may be composed of two circuits. For example, the first arm and the second arm in fig. 14 may be connected in series and simultaneously connected in parallel with two fixed resistors R connected in series to form one of two circuits. The third and fourth arms of figure 14 are used to connect in series, while connecting in parallel two further pairs of fixed resistors R connected in series, to form the other of the two circuits. Both circuits having the same input voltage U_i. In a similar manner to fig. 14, the output voltages of the two circuits were measured separately.

In a further alternative embodiment, the present invention provides that the counter-force measuring device may further comprise a first bridge circuit. The first bridge circuit consists of 4 pairs of strain gages arranged circumferentially symmetrically at a first height of the strain sensitive area. The processor can also obtain the resultant force of the contact load according to the output voltage of the first bridge circuit and the included angle between the resultant force of the contact load and the central axis.

The two strain gauges of each strain gauge pair of the first bridge circuit are arranged to be mounted in a T-shape or inverted T-shape at the same position. Fig. 15 shows a schematic diagram of a first bridge circuit. The 4 pairs of strain patches were Rz1 and Rc1, Rz2 and Rc2, Rz3 and Rc3, Rz4 and Rc4, respectively, each set to beThe mounting is in a T shape or an inverted T shape, wherein the longitudinal strain gauges are respectively designated as Rz1, Rz2, Rz3 and Rz4, and the transverse strain gauges are respectively designated as Rc1, Rc2, Rc3 and Rc4 in the counterclockwise direction with the X axis as a starting point. Wherein, the strain gauges Rz1 and Rz3 constitute a first arm, Rc1 and Rc3 constitute a second arm, Rc2 and Rc4 constitute a third arm, and Rz2 and Rz4 constitute a fourth arm. The first arm and the second arm form a first half-bridge, and the third arm and the fourth arm form a second half-bridge. The first bridge circuit formed by the first group of strain gauges is a conventional bridge circuit. For the first bridge circuit, measuring the output voltage U of the first bridge circuit_o. The first bridge circuit and the included angle measuring module have the same input voltage U_i。

In an embodiment of the invention, the first height and the second height are the same or different. The strain gage pairs of the first and second sets of strain gages may be arranged circumferentially crosswise with the first and second heights being the same. Under the condition that the first height and the second height are different, the strain gauge pairs of the first group of strain gauges and the second group of strain gauges can have a circumferential included angle or do not have a circumferential included angle.

The hoop included angle between each strain gage of the first group of strain gages and each strain gage of the second group of strain gages can be understood as the included angle between the vertical straight line of the central shaft and the installation position of the second group of strain gages and the second strain gage adjacent to the first strain gage in the second group of strain gages, and under the condition that the two groups of strain gages are not at the same height, the hoop included angle can be determined by mapping the two vertical straight lines to the same plane. The hoop included angle may be any value between 0 degrees and 90 degrees, but is not equal to 0 degrees and 90 degrees. The hoop angle between each strain gage of the first set of strain gages and each strain gage of the second set of strain gages can be set to be β, as shown in fig. 16. During the calculation, beta is a known quantity.

The functions performed by the controller can be configured separately, and in one embodiment, the counter force measuring device can include the first bridge circuit, the second bridge circuit, and the tilt angle sensing device described above. Correspondingly, the embodiment of the invention provides a force sensor assembly which comprises the counterforce measuring device.

Next, a description will be given of a reaction force measuring method provided by an embodiment of the present invention, which is used for a reaction force measuring device and can be executed by a controller. Fig. 17 shows a schematic diagram of some parameters involved in the counter force measurement method in the case of a force applied by tilting the force sensor assembly. As shown in fig. 17, it is assumed that an angle between the resultant force of the contact load and the central axis of the force sensor assembly is α, an angle between a plane formed by the resultant force of the contact load and the central axis of the force sensor assembly and a plane formed by the central axis and a mounting position of a strain gauge (which may be any strain gauge) is θ, and an inner radius of the strain sensitive region is r₁The outer radius of the strain sensitive region is r₂The vertical distance from the equivalent spherical center of the support area of the stress sensor assembly to the mounting position of the second group of strain gauges is h₁。r₁、r₂And h₁May be known in advance. The included angles in the embodiments of the present invention are relatively small angles. In the invention, the equivalent spherical center refers to the intersection point in the stress direction in the stress surface of the support area. And under the condition that the supporting area is a ball head type supporting area, the equivalent spherical center is a spherical center O point of the ball head type supporting area. The angle measurement module is taken as the second bridge circuit for explanation.

For a first bridge circuit, measuring an output voltage of the first bridge circuit and having:

in formula (2), U_oIs the output voltage of the first bridge circuit, U_iThe input voltage of the first bridge circuit is K, the sensitivity coefficient of the strain gauge is K, v is the Poisson's ratio of the material of the stress sensor assembly, E is the elastic modulus of the material of the stress sensor assembly, and F is the resultant force of the contact load.

From equation 2, the resultant force F of the contact load is the ratio of the included angle α to the output voltage and the input voltage of the first bridge circuit

I.e.:

in the formula (3), f_F() As a function of the resultant force F of the contact load.

For the second bridge circuit, the voltage output by each of the two half-bridges of the second bridge circuit is measured and recorded as the first half-bridge voltage U_x1And a second half-bridge voltage U_x2The second bridge circuit and the first bridge circuit may have the same input voltage U_iThen, it has:

in the formula:

the function f for calculating alpha can be obtained from the

formulas

4, 5 and 6_α()：

Accordingly, a function f can be obtained for calculating θ_θ()：

Substituting equation 7 into equation 3 yields the resultant force of the contact load, which is:

while the actual reaction force F_GThe vertical component of the resultant force F for the contact load is:

F_G＝F×(cosαcosγ_z+sinαcosθcosγ_x+sinαsinθcosγ_y) (formula 10)

Based on the formulas (2) to (10), the first embodiment of the reaction force measuring method provided by the present invention, as shown in fig. 18, may include the following steps:

in step S1710, an included angle α between the resultant force of the contact load borne by the force-receiving sensor assembly and the central axis of the force-receiving sensor assembly, an included angle θ between the plane formed by the central axis and the installation position of a strain gauge in the strain sensitive area of the force-receiving sensor assembly are obtained.

Alpha, theta can be obtained according to equations 4-8. Or any other suitable method may be used to obtain α, θ.

In step S1720, tilt angles γ between the X-axis, the Y-axis, and the Z-axis of the three-dimensional cartesian coordinate system and the gravity direction are detected_x,γ_y,γ_z。

The Z axis in the three-dimensional Cartesian coordinate system is the central axis of the stress sensor assembly, and the X axis points to the installation position of the strain gauge. Gamma ray_x,γ_y,γ_zCan be detected by the inclination angle detection device.

In step S1730, according to the resultant force F of the contact load, the included angle α between the resultant force of the contact load and the central axis, the included angle θ between the plane formed by the resultant force of the contact load and the central axis and the plane formed by the central axis and the installation position of a strain gauge, and the included angles γ between the X-axis, the Y-axis, and the Z-axis in the three-dimensional cartesian coordinate system and the gravity direction_x,γ_y,γ_zObtaining the reaction force F borne by the stress sensor assembly_G。

Wherein, can be based on the first bridgeOutput voltage U of formula circuit_oAnd obtaining the resultant contact load force F according to an included angle alpha between the resultant contact load force and the central axis, wherein the resultant contact load force F can be obtained according to a

formula

2 or 3. Alternatively, the resultant contact load force F may be detected using other force sensor assemblies.

The reaction force F borne by the force sensor assembly can be obtained according to the formula (10)_G。

Further, substituting equations 8 and 9 into equation 10 results in calculating the reaction force F_GFunction f of_g()：

According to the derivation process, the following steps are carried out: the calculation functions of α and θ are both related to the two half-bridge output voltages of the second bridge circuit, i.e., α and θ can be calculated from the two half-bridge output voltages of the second bridge circuit; reaction force F_GIs the output voltage U of the first bridge circuit_oTwo half-bridge output voltages U of a second bridge circuit_x1And U_x2Angle of gamma_x,γ_y,γ_zAs a function of (c).

Based on equation (11), taking the example that the reaction force measuring apparatus may include the first bridge circuit, the second bridge circuit and the inclination angle detecting device, the second embodiment of the reaction force measuring method provided by the present invention, as shown in fig. 19, may include the following steps:

in step S1810, the output voltage U of the first bridge circuit is obtained_o。

In step S1820, a first half-bridge voltage U output by each of two half-bridges of the second bridge circuit is obtained_x1And a second half-bridge voltage U_x2。

In step S1830, included angles γ between the X-axis, the Y-axis, and the Z-axis of the three-dimensional Cartesian coordinate system detected by the tilt detector and the gravity direction are obtained_x、γ_y、γ_z。

Output voltage U of first bridge circuit output by reaction force sensor assembly_oThe second bridgeFirst half-bridge voltage U of the circuit_x1And a second half-bridge voltage U_x2Angle of gamma_x、γ_y、γ_zMay be provided to the controller by wire or wirelessly.

In step S1840, according to the output voltage U of the first bridge circuit_oThe first half-bridge voltage U_x1The second half-bridge voltage U_x2And the included angles gamma between the X axis, the Y axis and the Z axis and the gravity direction respectively_x、γ_y、γ_zTo calculate the reaction force F_G。

In the first embodiment, after obtaining the parameters according to steps 1910 to 1930, in step S1940, an angle α between the resultant force of the contact load and the central axis, and an angle θ between a plane formed by the resultant force of the contact load and the central axis and a plane formed by the central axis and a mounting position of a strain gauge may be obtained according to the first half-bridge voltage and the second half-bridge voltage. Specifically, α may be calculated according to equation 7, and θ may be calculated according to equation 8. And then, obtaining the resultant force of the contact load according to the output voltage of the first bridge circuit and the included angle alpha between the resultant force of the contact load and the central axis, and specifically, calculating according to a formula 3 to obtain the resultant force of the contact load. And then, obtaining the counter force according to the contact load resultant force, the included angle between the contact load resultant force and the central axis, the included angle between the plane formed by the contact load resultant force and the central axis and the plane formed by the central axis and the installation position of a strain gauge, and the included angles between the X axis, the Y axis and the Z axis in the three-dimensional Cartesian coordinate system and the gravity direction respectively. Specifically, the reaction force can be calculated according to equation 10.

In the second embodiment, after obtaining the respective parameters according to steps 1810 to 1830, the reaction force may be calculated using a function for calculating the reaction force obtained in advance at step S1840.

In an alternative case, the function for calculating the counter force can be derived in advance from

equations

2, 4, 5, 6, 10.

In another alternative, the reaction force F is known according to equation 11_GBeing a first bridgeOutput voltage, two half-bridge output voltages of the second bridge, and included angle gamma_x,γ_y,γ_zIn the case of the function of (3), the function f for calculating the reaction force may be obtained by fitting experimental data using a neural network algorithm in advance_g() The model of (1). The input of the neural network algorithm is the independent variable in formula 11, and the output is the counterforce F_G。

The intermediate parameters alpha, theta, contact load resultant force and the like obtained in the first embodiment can be used for calculating other parameters under the condition of need, and the second embodiment can calculate the counter force more efficiently and quickly in real time.

The counter-force measuring method and the counter-force measuring device provided by the embodiment of the invention can effectively solve the influence of the side load on the counter-force measurement due to deflection deformation, inclination of the footing support plate and the like, and effectively improve the counter-force measurement precision.

Correspondingly, the embodiment of the invention also provides engineering machinery, and the engineering machinery is provided with the counter force measuring device or the stress sensor assembly according to any embodiment of the invention. The engineering machine can be a crane or a pump truck. Fire engine, etc., the measured counter force may be a leg counter force.

Further, embodiments of the present invention also provide a method for diagnosing a force sensor assembly, which may be performed by a controller and may be applied to any force sensor assembly having a strain sensitive area, for example, the method may be applied to the force sensor assembly provided by any of the embodiments of the present invention. When the force sensor assembly is used for measuring the counterforce of the support leg, the method can also be executed by a host controller of the engineering machine. In order to implement the method, a first bridge circuit composed of a first group of strain gauges and a third bridge circuit composed of a third group of strain gauges are arranged in a strain sensitive area of the stress sensor assembly. The first bridge circuit may be the same as the first bridge circuit described in the above-described reaction force measuring method. The third bridge circuit may be considered a redundant circuit of the first bridge circuit, which may be formed similarly to the first bridge circuit. The third bridge circuit is composed of a third group of strain gauges which are arranged at a third height position of the inner wall of the cavity of the strain sensitive area and are circumferentially and uniformly distributed, the third group of strain gauges and the first group of strain gauges can have the same number of strain gauge pairs, for example, 4 strain gauge pairs, and two strain gauges of each strain gauge pair are arranged to be installed in a T shape or an inverted T shape. The first height and the third height are the same or different. The pairs of strain gages of the first and third sets of strain gages may be arranged circumferentially crosswise, with the first and third heights being the same. The circumferential included angle of the first group of strain gauges and the third group of strain gauges can be arbitrary, preferably, the first group of strain gauges and the third group of strain gauges are arranged at the same height, and the circumferential included angle is 45 degrees. On the same height, the circumferential distribution of the first group of strain gauges and the third group of strain gauges is more uniform, and the precision is higher.

As shown in fig. 20, the method may include steps S1910 to S1940.

In step S1910, a reaction force first value is calculated from the output voltage of the first bridge circuit, and a reaction force second value is calculated from the output voltage of the third bridge circuit.

In one case, the first value of the counter force and the second value of the counter force can be calculated using conventional methods, without regard to deflection of the apparatus or tilting of the foot support plate. In this conventional method, assuming that the angle α between the resultant force of the contact load and the central axis of the force-receiving sensor assembly is 0, the counter force is equal to the resultant force of the contact load. Therefore, the reaction force first value can be calculated from the output voltage of the first bridge circuit using equation (2), α at the time of calculation takes 0, the reaction force is equal to the contact load resultant force, and the reaction force second value can be calculated similarly.

In another case, the first counter force value and the second counter force value may be calculated using the first implementation of the counter force measurement method provided in the embodiments of the present invention.

Specifically, a second bridge circuit composed of a second group of strain gauges can be further arranged in the stress sensor assembly, and two fixed resistors connected in series are connected in parallel in the second bridge circuit. This second bridge circuit is the same as the second bridge circuit described in the above-described reaction force measuring method. The second height of the second group of strain gauges can be the same as, partially the same as or different from the first height and the third height.

When calculating the first value of counter force, can acquire first bridge circuit's output voltage first half bridge voltage second half bridge voltage and X axle, Y axle, Z axle respectively with the contained angle of gravity direction, then according to 7 calculation contact load resultant force with the contained angle of axis, according to 8 calculation contact load resultant force with the contained angle between the plane that the axis constitutes with the mounted position of axis and a foil gage constitutes. Then, the resultant contact load force can be calculated according to equation 3. Thereafter, the first value of the reaction force may be calculated according to equation 10. When a second counter force value is calculated, the output voltage of a third bridge circuit, the first half-bridge voltage, the second half-bridge voltage and the included angles of the X axis, the Y axis and the Z axis with the gravity direction can be obtained, then the included angle of the contact load resultant force and the central axis is calculated according to a formula 7, and the included angle between the plane formed by the contact load resultant force and the central axis and the plane formed by the central axis and the installation position of a strain gauge is calculated according to a formula 8. Then, the resultant contact load force can be calculated according to equation 3. Thereafter, a second value of the reaction force may be calculated according to equation 10.

In yet another case, the first counter force value and the second counter force value may be calculated using the second implementation of the leg counter force measurement method provided in the embodiments of the present invention.

Specifically, a second bridge circuit composed of a second group of strain gauges may be further provided in the leg reaction force sensor assembly, and two fixed resistors connected in series are connected in parallel in the second bridge circuit. This second bridge circuit is the same as the second bridge circuit described in the above-described leg reaction force measurement method. When the first value of the reaction force is calculated, the output voltage of the first bridge circuit, the first half-bridge voltage, the second half-bridge voltage, and the included angles between the X-axis, the Y-axis, and the Z-axis and the gravity direction respectively can be obtained, and then the first value of the reaction force is calculated by using a function which is obtained in advance and used for calculating the reaction force of the support leg. When the second counter force value is calculated, the output voltage of the third bridge circuit, the first half-bridge voltage, the second half-bridge voltage, and the included angles between the X axis, the Y axis, and the Z axis and the gravity direction respectively may be obtained, and then the second counter force value may be calculated using a function obtained in advance for calculating the counter force of the leg.

In step S1920, it is determined whether or not the difference between the first reaction force value and the second reaction force value is smaller than a difference threshold.

Specifically, it may be determined that the difference between the first value of the reaction force and the second value of the reaction force is smaller than the difference threshold if the following condition is satisfied:

wherein, X₁(t) is a first value of the reaction force at the present time, X₂(t) is the second value of the reaction force at the current time, t is the current time, η_XA difference amount threshold. It is to be understood that the determination conditions shown in equation 13 are for example only and not for limitation.

In step S1930, it is determined whether or not there is a data transition between the first reaction force value and the second reaction force value.

Determining that there is no data transition in both the first value of the counter force and the second value of the counter force if the following condition is satisfied:

|X₁(t)-(2X₁(t-T)-X₁(t-2T))|＜a_X(formula 16)

|X₂(t)－(2x₂(t-T)-X₂(t-2T))|＜a_X(formula 17)

Wherein, X₁(t) is a first value of the reaction force at the present time, X₂(t) is the second value of the reaction force at the current time, t is the current time, η_XA difference threshold, T is a sampling period, a_XTo measure the continuity threshold. The sampling period T is a self-defined time period and is a period for judging whether data abnormally jumps. In the embodiment of the invention, the measured value used for calculating the counterforce of the supporting leg is the result after filtering by the filter, and 1/T needs to be far larger than the high cut-off frequency of the filterAnd (4) rate.

It is to be understood that the judgment conditions shown in equations 16 and 17 are for example only and not for limitation.

In step S1940, it is determined that the force sensor assembly is not malfunctioning when a difference between the first reaction force value and the second reaction force value is smaller than a difference threshold and there is no data transition between the first reaction force value and the second reaction force value.

Step S1920 and step S1930 may be executed simultaneously, or both may be executed in any order, wherein in case that the judgment result of one of the steps is no, the other step may not be executed any more, and it is determined that the force-receiving sensor assembly has a fault. Through mutual inspection and self-checking of the first counter force value and the second counter force value, whether the stress sensor assembly has a fault or not can be effectively judged.

Further, as described above, the force sensor assembly can be used as a leg reaction force sensor assembly to measure leg reaction force, and can be installed at the vertical support cylinder piston rod body of the engineering machinery leg. In the case where it is determined that the force sensor assembly is not faulty, a final leg reaction force may be determined from the first reaction force value and the second reaction force value. Final leg reaction force F_G1(t) may be an average of the first value of the reaction force and the second value of the reaction force, and the calculation formula is as follows:

alternatively, the final leg reaction force may be calculated using a weighted average, or either one of the reaction force first value and the reaction force second value may be selected as the final leg reaction force. Where the force sensor assembly is used to measure other counterforces, such as leg counterforces, the method described herein may also be used to determine the resulting counterforces.

The method for diagnosing the stressed sensor assembly provided by the embodiment of the invention can further judge the reliability of the final measurement result of the counterforce of the supporting leg. After the final support leg counter force is determined, the current weight estimation of the whole vehicle and the bending moment vector estimation based on the center position of the frame of the whole vehicle can be obtained from the torque limiter data of the engineering machinery, and then the reliability of the measurement result of the stress sensor assembly is determined according to the final support leg counter force of each support leg of the engineering machinery, the current weight estimation of the whole vehicle and the bending moment vector estimation based on the center position of the frame of the whole vehicle.

Specifically, the measurement result of the force sensor assembly is determined to have reliability under the condition that the following conditions are satisfied:

and is

in order to estimate the current weight of the whole vehicle,

the final leg reaction force vector determined for the leg numbered i. The magnitude of the final leg reaction force vector is the final leg reaction force calculated above, and the direction is vertically upward. Vehicle capable of being completedThe center of the frame is the origin, and the coordinate vector of the support position of the corresponding support leg is calculated to obtain

When the conditions of equation 13, equation 16, equation 17, equation 18, and equation 19 are satisfied, the force sensor assembly has no failure and the measurement results have reliability. And when any one or more of the conditions of formula 13, formula 16, formula 17, formula 18, and formula 19 is not satisfied, it can be determined that the force sensor assembly has a failure and the measurement result has no reliability. According to the method for diagnosing the stress sensor assembly provided by the embodiment of the invention, the measurement accuracy of the stress sensor assembly can be further improved.

Embodiments of the present invention also provide a system for diagnosing a force sensor assembly, which may be used for any force sensor assembly having a strain sensitive region. As shown in fig. 21, the system may include: a first bridge circuit 2010 consisting of a first set of strain gages and a third bridge circuit 2020 consisting of a third set of strain gages; and a controller 2030 for determining whether or not the leg reaction force sensor assembly is malfunctioning based on the output voltage of the first bridge circuit and the output voltage of the third bridge circuit. Controller 2030 may specifically perform a method of diagnosing a force sensor assembly according to any embodiment of the present invention.

The first and third sets of strain gages may be located in a strain sensitive region of the force sensor assembly, for example, when the force sensor assembly is a force sensor assembly as described in any of the embodiments of the present application, the first and third sets of strain gages may be located in an inner wall of a cavity of the strain sensitive region. The first and third sets of strain gages may include an equal number of pairs of strain gages, which may be configured to be mounted in a T-shape or an inverted T-shape. The first set of strain gages is arranged in an annular symmetry at a first height of the strain sensitive region, and the third set of strain gages is arranged in an annular symmetry at a third height of the strain sensitive region. For a detailed description of the first bridge circuit formed by the first group of strain gauges, a detailed description of the third bridge circuit formed by the third group of strain gauges, and a detailed description of the steps executed by the controller, please refer to the detailed description of the method for diagnosing the force-receiving sensor assembly, and will not be described herein again.

Further, in the case that the force sensor assembly is installed at a piston rod body of a vertical support cylinder of a leg of an engineering machine for measuring a counter force of the leg, the system for diagnosing the force sensor assembly may further include: and the main machine controller acquires the current weight estimation of the whole vehicle and the bending moment vector estimation based on the center position of the frame of the whole vehicle from the data of the moment limiter. The host controller is also used for determining final support reaction force according to the first reaction force value and the second reaction force value under the condition that the support reaction force sensor assembly has no fault; and determining the reliability of the measurement result of the stress sensor assembly according to the final support leg counter force of each support leg of the engineering machinery, the current weight estimation of the whole vehicle and the bending moment vector estimation based on the central position of the frame of the whole vehicle.

The specific working principle and benefits of the system for diagnosing a stressed sensor assembly provided by the embodiment of the invention are the same as those of the method for diagnosing a support leg reaction force sensor assembly provided by the embodiment of the invention, and the detailed description is omitted here.

Correspondingly, the embodiment of the invention also provides engineering machinery, which comprises the system for diagnosing the stress sensor assembly provided by any embodiment of the invention and the stress sensor assembly provided by any embodiment of the invention, wherein the first group of strain gauges and the third group of strain gauges can be arranged on the inner wall of the cavity of the cylinder-type strain sensitive area of the supporting leg reaction force sensor assembly.

Further, the system for diagnosing a force sensor assembly may further include: a second bridge circuit composed of a second set of strain gages, and a tilt angle detection device. Wherein the second bridge circuit is connected in parallel with two fixed resistors connected in series, and the second bridge circuit is the same as the second bridge circuit described in the counter force measuring method. The inclination angle detection equipment can be an MEMS inclination angle sensor or an acceleration sensor and is used for detecting included angles between an X axis, a Y axis and a Z axis in a three-dimensional Cartesian coordinate system and the gravity direction respectively, wherein the Z axis in the three-dimensional Cartesian coordinate system is a central axis of the supporting leg reaction force sensor assembly, and the X axis points to the installation position of a strain gauge. The host controller can determine a first counter force value according to the output voltage of the first bridge circuit, the first half-bridge voltage of the second bridge circuit, the second half-bridge voltage of the second bridge circuit, and the included angles between the X-axis, the Y-axis and the Z-axis and the gravity direction respectively. The controller may determine a second value of the counter force according to the output voltage of the third bridge circuit, the first half-bridge voltage of the second bridge circuit, the second half-bridge voltage of the second bridge circuit, and angles between the X-axis, the Y-axis, and the Z-axis and the gravity direction, respectively. For a detailed description of the calculation of the first value of the reaction force and the second value of the reaction force by the second bridge circuit composed of the second group of strain gauges and the host controller, please refer to a detailed description of the method for diagnosing the stressed sensor assembly, which will not be described herein again.

The second set of strain gages may be mounted on an inner wall of the cavity of the strain sensitive region of the leg reaction sensor assembly. The first bridge circuit, the second bridge circuit and the third bridge circuit can be respectively connected with the controller through cables. In the alternative, the controller may be connected wirelessly.

The mounting heights of the strain gauge pairs belonging to the same group of strain gauges are the same, and the mounting heights of the strain gauge pairs belonging to different groups of strain gauges can be the same or different. In an expandable embodiment, the controller may control the alarm device to give an alarm, where the alarm device may be an audible and visual alarm or the like, in case it is determined that the force sensor assembly is faulty and/or the measurement result is not reliable. Or the controller can control a display device of the engineering machinery to give out a prompt so as to draw the attention of a driver and ensure safe operation.

FIG. 22 illustrates a block diagram of an apparatus for diagnosing a force sensor assembly, in accordance with an embodiment of the present invention. As shown in fig. 22, an embodiment of the present invention further provides an apparatus for diagnosing a force sensor assembly, which may be used for a host controller of a construction machine. The apparatus may include: a calculating module 2110 for calculating a first counter force value according to the output voltage of the first bridge circuit and a second counter force value according to the output voltage of the third bridge circuit; a first determining module 2120 configured to determine whether a difference between the first reaction force value and the second reaction force value is smaller than a difference threshold; a second judging module 2130, configured to judge whether there is a data transition between the first counter force value and the second counter force value; and a first determining module 2140 configured to determine that the force sensor component is not faulty if the difference between the first counter force value and the second counter force value is smaller than a difference threshold and there is no data transition between the first counter force value and the second counter force value.

In some embodiments, the force sensor assembly is installed at a piston rod body of a vertical support cylinder of a support leg of an engineering machine for measuring a reaction force of the support leg, and the apparatus may further include: a second determination module for determining a final leg reaction force according to the first reaction force value and the second reaction force value when the leg reaction force sensor assembly is not in failure; the acquisition module is used for acquiring the current weight estimation of the whole vehicle and the bending moment vector estimation based on the center position of the frame of the whole vehicle from the torque limiter data of the engineering machinery; and the third determining module is used for determining the reliability of the measuring result of the stress sensor assembly according to the final support leg counter force of each support leg of the engineering machinery, the current weight estimation of the whole vehicle and the bending moment vector estimation based on the center position of the frame of the whole vehicle.

In some embodiments, the calculation module 2110 may include: a first obtaining unit, configured to obtain an output voltage of the first bridge circuit and an output voltage of the third bridge circuit; a second obtaining unit, configured to obtain a first half-bridge voltage and a second half-bridge voltage output by each of two half-bridges of the second bridge circuit; the third acquisition unit is used for acquiring included angles between an X axis, a Y axis and a Z axis in a three-dimensional Cartesian coordinate system and the gravity direction respectively, wherein the Z axis in the three-dimensional Cartesian coordinate system is a central axis of the supporting leg reaction force sensor assembly, and the X axis points to the installation position of a strain gauge; a computing unit to: calculating a first counter force value according to the output voltage of the first bridge circuit, the first half-bridge voltage, the second half-bridge voltage and the included angles of the X axis, the Y axis and the Z axis with the gravity direction respectively; and calculating the second counter force value according to the output voltage of the third bridge circuit, the first half-bridge voltage, the second half-bridge voltage and the included angles of the X axis, the Y axis and the Z axis with the gravity direction respectively.

The specific working principle and benefits of the device for diagnosing a force-receiving sensor assembly provided by the embodiment of the invention are the same as those of the method for diagnosing a force-receiving sensor assembly provided by the embodiment of the invention, and the detailed description is omitted here.

Accordingly, an embodiment of the present invention further provides a machine-readable storage medium, where the machine-readable storage medium has instructions stored thereon, and the instructions are configured to cause a machine to perform: a method of measuring a counter force according to any embodiment of the invention; and/or a method of diagnosing a force sensor assembly according to any embodiment of the present invention.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

In a typical configuration, a computing device includes one or more processors (CPUs), input/output interfaces, network interfaces, and memory.

The memory may include forms of volatile memory in a computer readable medium, Random Access Memory (RAM) and/or non-volatile memory, such as Read Only Memory (ROM) or flash memory (flash RAM). The memory is an example of a computer-readable medium.

Computer-readable media, including both non-transitory and non-transitory, removable and non-removable media, may implement information storage by any method or technology. The information may be computer readable instructions, data structures, modules of a program, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), other types of Random Access Memory (RAM), Read Only Memory (ROM), Electrically Erasable Programmable Read Only Memory (EEPROM), flash memory or other memory technology, compact disc read only memory (CD-ROM), Digital Versatile Discs (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information that can be accessed by a computing device. As defined herein, a computer readable medium does not include a transitory computer readable medium such as a modulated data signal and a carrier wave.

It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in the process, method, article, or apparatus that comprises the element.

The above are merely examples of the present application and are not intended to limit the present application. Various modifications and changes may occur to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A method of diagnosing a force sensor assembly having a first bridge circuit comprising a first set of strain gages and a third bridge circuit comprising a third set of strain gages disposed therein, the method comprising:

calculating a first value of a reaction force according to the output voltage of the first bridge circuit, and calculating a second value of the reaction force according to the output voltage of the third bridge circuit;

judging whether the difference between the first reaction force value and the second reaction force value is smaller than a difference threshold value;

judging whether data jumping exists between the first counter force value and the second counter force value; and

and determining that the force sensor component has no fault when the difference between the first reaction force value and the second reaction force value is smaller than a difference threshold value and no data jump exists between the first reaction force value and the second reaction force value.

2. The method of claim 1, wherein the determining whether the amount of difference between the first value of the reaction force and the second value of the reaction force is less than a difference threshold value comprises: determining that a difference between the first value of the reaction force and the second value of the reaction force is less than the difference threshold value when:

3. The method of claim 1 or 2, wherein determining whether there is a data transition between the first counter force value and the second counter force value comprises: determining that there is no data transition in both the first value of the counter force and the second value of the counter force if the following condition is satisfied:

|X₁(t)-(2X₁(t-T)-X₁(t-2T))|＜a_X，

|X₂(t)-(2X₂(t-T)-X₂(t-2T))|＜a_X，

4. The method of claim 1, wherein the force sensor assembly is mounted at a vertical support cylinder piston rod body of a support leg of the construction machine for measuring a support leg reaction force, the method further comprising:

determining a final leg reaction force according to the first reaction force value and the second reaction force value under the condition that the stress sensor assembly has no fault;

acquiring current weight estimation of the whole vehicle and bending moment vector estimation based on the center position of a frame of the whole vehicle from torque limiter data of the engineering machinery; and

and determining the reliability of the measurement result of the stress sensor assembly according to the final support leg counter force of each support leg of the engineering machinery, the current weight estimation of the whole vehicle and the bending moment vector estimation based on the central position of the frame of the whole vehicle.

5. The method of claim 4, wherein determining the reliability of the measurement of the force sensor assembly based on the final leg reaction force of each leg of the work machine, the current weight estimate of the entire vehicle, and the bending moment vector estimate based on the center position of the frame of the entire vehicle comprises: determining that the measurement of the force sensor assembly has reliability if the following conditions are met:

and is

in order to estimate the current weight of the whole vehicle,

based on the bending moment vector of the center position of the whole vehicle frameEstimate, δ_GEstimating an error threshold, δ, for a preset weight_MAn error threshold is estimated for a preset bending moment,

the final leg reaction force vector determined for the leg numbered i.

6. The method of claim 1, wherein the force sensor assembly comprises:

the upper surface of the bearing area is used for bearing the load applied by the structure to be tested;

a fixed region for mechanical connection with a structure under test, wherein the fixed region is disposed around the load-bearing region;

the strain sensitive area is positioned below the fixed area and is provided with a cavity; and

and the support region is positioned below the strain sensitive region to play a supporting role.

7. The method of claim 6, wherein a second bridge circuit comprising a second set of strain gages is provided in the force sensor assembly, wherein two fixed resistors connected in series are connected in parallel in the second bridge circuit,

calculating a first value of a reaction force from the output voltage of the first bridge circuit and a second value of the reaction force from the output voltage of the third bridge circuit includes:

acquiring the output voltage of the first bridge circuit and the output voltage of the third bridge circuit;

acquiring a first half-bridge voltage and a second half-bridge voltage which are respectively output by two half-bridges of the second bridge circuit;

acquiring included angles between an X axis, a Y axis and a Z axis in a three-dimensional Cartesian coordinate system and the gravity direction respectively, wherein the Z axis in the three-dimensional Cartesian coordinate system is a central axis of the supporting leg reaction force sensor assembly, and the X axis points to the installation position of a strain gauge;

calculating a first counter force value according to the output voltage of the first bridge circuit, the first half-bridge voltage, the second half-bridge voltage and the included angles of the X axis, the Y axis and the Z axis with the gravity direction respectively; and

and calculating the second counter force value according to the output voltage of the third bridge circuit, the first half-bridge voltage, the second half-bridge voltage and the included angles of the X axis, the Y axis and the Z axis with the gravity direction respectively.

8. An apparatus for diagnosing a force sensor assembly having a first bridge circuit comprising a first set of strain gages and a third bridge circuit comprising a third set of strain gages disposed therein, the apparatus comprising:

the calculating module is used for calculating a first counter force value according to the output voltage of the first bridge circuit and a second counter force value according to the output voltage of the third bridge circuit;

a first judgment module for judging whether the difference between the first counter force value and the second counter force value is smaller than a difference threshold;

the second judging module is used for judging whether data jumping exists between the first counter force value and the second counter force value; and

and a first determination module configured to determine that the force sensor assembly is not faulty when a difference between the first reaction force value and the second reaction force value is smaller than a difference threshold and no data transition is present between the first reaction force value and the second reaction force value.

9. The apparatus of claim 8, wherein the first determining module is configured to determine that the first value of the reaction force and the second value of the reaction force differ by an amount less than the difference threshold if:

10. The apparatus of claim 8 or 9, wherein the second determining module is configured to determine that there is no data transition between the first counter force value and the second counter force value if the following condition is met:

|X₁(t)-(2X₁(t-T)-X₁(t-2T))|＜a_X，

|X₂(t)-(2X₂(t-T)-X₂(t-2T))|＜a_X，

11. The apparatus of claim 8, wherein the force sensor assembly is mounted at a piston rod body of a vertical support cylinder of the engineering machinery leg for measuring a leg reaction force, the apparatus further comprising:

a second determination module for determining a final leg reaction force according to the first reaction force value and the second reaction force value when the leg reaction force sensor assembly is not in failure;

the acquisition module is used for acquiring the current weight estimation of the whole vehicle and the bending moment vector estimation based on the center position of the frame of the whole vehicle from the torque limiter data of the engineering machinery; and

and the third determining module is used for determining the reliability of the measuring result of the stress sensor assembly according to the final support leg counter force of each support leg of the engineering machinery, the current weight estimation of the whole vehicle and the bending moment vector estimation based on the center position of the frame of the whole vehicle.

12. The apparatus of claim 11, wherein the third determination module is configured to determine that the measurement of the force sensor assembly is reliable if the following condition is met:

and is

in order to estimate the current weight of the whole vehicle,

the final leg reaction force vector of the leg numbered i.

13. The apparatus of claim 8, wherein the leg reaction force sensor assembly comprises:

14. The apparatus of claim 13, wherein a second bridge circuit comprising a second set of strain gages is disposed in the force sensor assembly, and two fixed resistors connected in series are connected in parallel in the second bridge circuit, and the computing module comprises:

a first obtaining unit, configured to obtain an output voltage of the first bridge circuit and an output voltage of the third bridge circuit;

a second obtaining unit, configured to obtain a first half-bridge voltage and a second half-bridge voltage output by each of two half-bridges of the second bridge circuit;

the third acquisition unit is used for acquiring included angles between an X axis, a Y axis and a Z axis in a three-dimensional Cartesian coordinate system and the gravity direction respectively, wherein the Z axis in the three-dimensional Cartesian coordinate system is a central axis of the supporting leg reaction force sensor assembly, and the X axis points to the installation position of a strain gauge;

a computing unit to:

15. A machine-readable storage medium having stored thereon instructions for causing a machine to perform the method of diagnosing a force sensor assembly of any of claims 1-7.