CN114018472A

CN114018472A - Swing arm, calibration device, method and system for torque sensor calibration

Info

Publication number: CN114018472A
Application number: CN202111232267.XA
Authority: CN
Inventors: 宋庭科; 田连刚; 安然
Original assignee: Feixi Technology Co ltd; Foshan Feixi Robot Technology Co ltd
Current assignee: Feixi Technology Co ltd; Foshan Feixi Robot Technology Co ltd
Priority date: 2021-10-22
Filing date: 2021-10-22
Publication date: 2022-02-08
Anticipated expiration: 2041-10-22
Also published as: CN114018472B

Abstract

The invention relates to a swing arm for calibrating a torque sensor, which comprises a fixed seat and at least one support arm, wherein the fixed seat is provided with a shaft hole which is configured to be used for connecting a transmission shaft of the torque sensor; the fixing seat is further provided with a plurality of first mounting areas which are circumferentially arranged around the shaft hole, each first mounting area is provided with a first mounting direction, the first mounting direction is parallel to one radial direction of the shaft hole, and each first mounting area is configured to be used for mounting the level bubble along the first mounting direction; one end of the support arm is connected with the fixed seat and is vertical to the axis of the shaft hole, and the other end of the support arm is suspended and is configured to be connected with a load. The first installation region of installation air level has been reserved to the swing arm to limited the first installation orientation of first installation region, can form accurate angle for the installation of air level and prescribe a limit to, make the air level install behind the first installation region, can be according to the directional angle of first installation orientation, supplementary angle to the swing arm for the horizontality is adjusted.

Description

Swing arm, calibration device, method and system for torque sensor calibration

Technical Field

The invention relates to the technical field of robots, in particular to a swing arm for calibrating a torque sensor, a torque sensor calibration device, a torque sensor calibration method, a torque sensor calibration system and a robot calibration system.

Background

With the development of the robot technology, the human-computer cooperative type mechanical arm gets more and more attention, and a robot joint is used as an important ring in the human-computer cooperative type mechanical arm and has very important influence on the operation precision of the mechanical arm. Therefore, the moment sensor is arranged in the robot joint, the moment sensor can transmit moment on one hand, and can measure the moment value of the sensor on the other hand, the measured moment value of the sensor is compared with the theoretical moment, the difference between the measured moment value and the theoretical moment can be calculated, and the robot-cooperative mechanical arm can be adjusted according to the difference, so that the robot-cooperative mechanical arm can accurately reach a preset position. Therefore, in order to accurately operate the human-machine cooperative type robot arm, calibration of the torque sensor in the robot joint becomes important.

At present, when a torque sensor is calibrated, the torque sensor is fixedly arranged on a support, a swing arm for assisting in measuring torque is arranged on a transmission shaft of the torque sensor, test objects with different weights are hung at the tail end of the swing arm, a sensor torque value measured by the torque sensor is utilized on one side, a theoretical torque is calculated on the other side according to the actual hanging condition, and the sensor torque value and the theoretical torque are compared, so that whether the torque sensor needs to be calibrated or not can be judged.

However, in the calibration method for the torque sensor, when the angle of the swing arm to the horizontal plane is adjusted, a person skilled in the art mostly adjusts the angle of the swing arm by visual observation, which undoubtedly causes an error in the measurement result of the torque, and thus results in an inaccurate calibration result of the torque sensor.

Disclosure of Invention

Based on this, it is necessary to provide a swing arm, a torque sensor calibration device, a method and a system, and a robot calibration system for torque sensor calibration, aiming at the problem of inaccurate calibration of the torque sensor.

The invention provides a swing arm for torque sensor calibration, comprising:

the fixing seat is provided with a shaft hole, and the shaft hole is configured to be connected with a transmission shaft of the torque sensor; the fixed seat is further provided with a plurality of first mounting areas arranged circumferentially around the shaft hole, each first mounting area is provided with a first mounting direction, the first mounting direction is parallel to one radial direction of the shaft hole, and each first mounting area is configured to be used for mounting the level bubble along the first mounting direction;

and one end of the support arm is connected with the fixed seat and is vertical to the axis of the shaft hole, and the other end of the support arm is suspended and is configured to be connected with a load.

In one embodiment, the included angle between the first installation direction of each first installation area and the same support arm is within a preset distribution included angle range; and/or the included angle of the first installation direction of the adjacent first installation area is within the range of the preset interval included angle.

In one embodiment, the included distribution angle ranges from 0 ° -360 °, 0 ° -90 °, 90 ° -180 °, 180 ° -270 °, or 270 ° -360 °; and/or the included angle of the interval is in the range of 5-45 degrees.

In one embodiment, at least one of the support arms includes a reference support arm, the distribution included angle ranges from 0 ° to 360 °, the number of the first installation areas is 36, the included angles between the first installation directions of adjacent first installation areas are 10 °, and the included angle between the first installation direction of one of the installation areas and the reference support arm is 0 °;

or at least one of the support arms comprises a reference support arm, the number of the first installation areas is 4, the distribution included angle ranges from 0 degree to 90 degrees, and the included angles between the first installation directions of the 4 first installation areas and the reference support arm are respectively 0 degree, 30 degrees, 45 degrees and 90 degrees;

or at least one of the support arms comprises a reference support arm, the distribution included angle range is 90-180 degrees, the number of the first installation areas is 4, and the included angles between the first installation directions of the 4 first installation areas and the reference support arm are 90 degrees, 120 degrees, 135 degrees and 180 degrees respectively;

or at least one of the support arms comprises a reference support arm, the distribution included angle range is 180 degrees to 270 degrees, the number of the first installation areas is 4, and the included angles between the first installation directions of the 4 first installation areas and the reference support arm are 180 degrees, 210 degrees, 255 degrees and 270 degrees respectively;

or, at least one of the support arms comprises a reference support arm, the distribution included angle range is 270 degrees to 360 degrees, the number of the first installation areas is 4, and the included angles between the first installation directions of the 4 first installation areas and the reference support arm are 270 degrees, 300 degrees, 315 degrees and 360 degrees respectively.

In one embodiment, the first installation area is an installation groove formed in the end face of the fixed seat, and the installation groove is configured for installing a level bubble along the first installation direction;

or, the first mounting area is an adhesive area arranged on the end surface of the fixed seat, and the adhesive area is configured to be used for adhering a level bubble along the first mounting direction;

or, the first installation area is a magnetic attraction area arranged on the end surface of the fixing seat, and the magnetic attraction area is configured to be used for magnetically assembling the level bubble along the first installation direction.

In one embodiment, the number of the support arms is 2, the included angle of 2 support arms is 180 °, at least one support arm is provided with at least one second installation area, the second installation area has a second installation direction, the second installation direction is parallel to the length direction of the support arm, and the second installation area is configured to install the level bubble along the second installation direction.

In one embodiment, the second mounting region is located at the cantilevered end of the arm.

In one embodiment, at least one of the first mounting regions has a vial mounted therein; and/or a vial is mounted in at least one of the second mounting regions.

In one embodiment, the support arm is provided with a plurality of hoisting parts along the length direction, the distance between every two adjacent hoisting parts is equal, and the hoisting parts are configured to be used for connecting loads.

In one embodiment, the hoisting part is a hoisting hole formed in the support arm.

The invention also provides a torque sensor calibration device, comprising:

a bracket configured for mounting a torque sensor to be calibrated;

the shaft hole of the swing arm is configured to be used for connecting a transmission shaft of the torque sensor.

The invention also provides a torque sensor calibration method, and according to the torque sensor calibration device, the method comprises the following steps:

installing a torque sensor to be calibrated between the bracket and the swing arm;

rotating the swing arm, rotating the swing arm to a preset target angle by means of a level bubble located in the first installation area, and connecting a load to the swing arm;

and acquiring a sensor torque value of the swing arm by using the torque sensor, calculating a theoretical torque value of the swing arm, and calculating a torque difference value between the sensor torque value and the theoretical torque.

In one embodiment, the method comprises the following steps:

the method comprises the following steps: setting a plurality of target angles, and calculating the moment difference value under each target angle in sequence;

step two: when all the moment difference values are within a preset threshold value, finishing calibration;

step three: and when any one torque difference value is not within a preset threshold value, the torque sensor is overhauled, and the first step and the second step are repeated.

The invention also provides a torque sensor calibration system, comprising:

the torque sensor calibration device;

the processing unit is configured to acquire a sensor torque value of the swing arm measured by the torque sensor, calculate a theoretical torque value of the swing arm, calculate a torque difference value between the sensor torque value and the theoretical torque, and compare the torque difference value with a preset threshold value to generate a calibration result.

In one embodiment, the processing unit includes:

a first processor configured to acquire a sensor torque value of the swing arm measured by the torque sensor;

a second processor configured for calculating a theoretical moment value of the swing arm;

a third processor configured to calculate a torque difference value between the sensor torque value and the theoretical torque, and compare the torque difference value with a preset threshold value to generate a calibration result.

The invention also provides a robot calibration system, which is characterized by comprising:

the swing arm; or,

the torque sensor calibration device; or,

the torque sensor calibrates the system.

Above-mentioned a swing arm for torque sensor calibration, reserved the first installation region who is used for installing the air level, and limited first installation orientation of first installation region, so, can form accurate angle for the installation of air level and prescribe a limit to, make the air level install behind first installation region, can be according to the directional angle of first installation orientation, supplementary angle to the swing arm for the horizontality is adjusted, when this can guarantee that the swing arm is used for correcting torque sensor, provide accurate swing arm turned angle, and then guarantee that the correction result is accurate.

Drawings

FIG. 1 is a front view of a swing arm according to one embodiment of the present invention;

FIG. 2 is a front view of the anchor block in accordance with one embodiment of the present invention;

FIG. 3 is a schematic view of a first mounting region and a first mounting direction thereof according to an embodiment of the present invention;

FIG. 4 is a schematic view of a first mounting region and a first mounting direction thereof according to another embodiment of the present invention;

FIG. 5 is a schematic view of a second mounting region and a second mounting direction thereof according to an embodiment of the present invention;

FIG. 6 is a perspective view of a swing arm according to one embodiment of the present invention;

FIG. 7 is a perspective view of a mounting base according to one embodiment of the present invention;

FIG. 8 is a perspective view of a vial-mounted holder according to one embodiment of the present invention;

FIG. 9 is an enlarged view of a portion of the mounting bracket shown in FIG. 8;

FIG. 10 is a front view of a torque sensor calibration device according to one embodiment of the present invention;

FIG. 11 is a perspective view of a torque sensor calibration device according to one embodiment of the present invention;

fig. 12 is a theoretical schematic diagram of the deflection of the swing arm according to an embodiment of the present invention.

Reference numerals:

100. swinging arms; 200. a torque sensor; 300. a support;

110. a fixed seat; 120. a support arm; 130. a level bubble;

111. a shaft hole; 112. a first mounting area; 113. a first mounting direction;

121. a second mounting area; 122. a second mounting direction; 123. a hoisting part.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

Referring to fig. 1 to 9, an embodiment of the present invention provides a swing arm 100 for calibrating a torque sensor 200, where the swing arm 100 includes: the moment sensor comprises a fixed seat 110 and at least one support arm 120, wherein the fixed seat 110 is provided with a shaft hole 111, and the shaft hole 111 is configured to be used for connecting a transmission shaft of the moment sensor 200; the fixed seat 110 is further provided with a plurality of first mounting regions 112 circumferentially arranged around the shaft hole 111, the first mounting regions 112 have a first mounting direction 113, the first mounting direction 113 is parallel to one radial direction of the shaft hole 111, and the first mounting regions 112 are configured for mounting the level bubble 130 along the first mounting direction 113; one end of the support arm 120 is connected with the fixing base 110 and is perpendicular to the axis of the shaft hole 111, the other end of the support arm 120 is suspended and configured to be connected with a load, the number of the support arms 120 can be one or more, and when the number of the support arms 120 is multiple, the support arms 120 can be arranged in a mutually matched manner at a proper angle, for example, the number of the support arms 120 is two, the two support arms 120 can be arranged in a state of having an included angle according to requirements, and the included angle can be 180 degrees or any other angle.

Vial 130, also known as vial 130, vial 130 has a different precision, and the measurement results are more accurate for the higher precision vial 130. The level bubble 130 is provided with a scale which can accurately reflect whether the rotation of the swing arm 100 reaches a desired rotation angle, and a plurality of pieces of relatively accurate rotation angle information of the swing arm 100 can be obtained without any program control. The precision of vial 130 refers to: the angle of inclination of the vial 130 when the bubble is moved 2mm axially along the vial 130. The fixing base 110 may be square, circular, or irregular, and is not limited herein. Moreover, the swing arm 100 can be used not only for the robot joint to quickly calibrate and measure the internal torque sensor 200 at a specific angle, but also for some occasions with precise requirements on specific angular positions. The relative relationship between the arm 120 and the fixing base 110 is that the arm 120 can be perpendicular to the axis of the axial hole 111 or at an angle, which depends on the requirement of calibrating the torque sensor 200, and is not limited herein.

This swing arm 100 has reserved the first installation region 112 that is used for installing the air level 130 to the first installation direction 113 of first installation region 112 has been injectd, so, can form accurate angle for the installation of air level 130 and have been injectd, make air level 130 install behind first installation region 112, can be according to the directional angle of first installation direction 113, supplementary angle to swing arm 100 for the horizontality is adjusted, when this can guarantee that swing arm 100 is used for correcting torque sensor 200, provide accurate swing arm 100 turned angle, and then guarantee that the result of correction is accurate. The angle adjusting mode is simple, rapid and direct, the possibility of misoperation basically does not exist, and the high-precision angle judging method is provided on the premise of ensuring low processing and using cost.

In addition, in order to facilitate the identification of the pointing angle of the first mounting direction 113 of each first mounting region 112, an angle marking device may be further disposed on the fixing base 110 and circumferentially surround the shaft hole 111, and the angle marking device is disposed based on the pointing angle capable of assisting in identifying the first mounting direction 113, for example, the angle marking device and the shaft hole are concentrically disposed. In some embodiments, the angle marking device is an angle scale having specific scales, so as to assist in identifying the pointing angle of the first mounting direction 113 and finding the angle on the angle scale at which the vial 130 points corresponding to the scales.

In the arrangement of the first mounting regions 112, the first mounting regions 112 may be a plurality of first mounting regions 112 that are capable of being used to mount a corresponding number of vials 130, although the specific number of vials 130 mounted may be equal to or less than the number of first mounting regions 112, and is not limited thereto. When the number of the first mounting areas 112 is plural, the included angle between the first mounting direction 113 of each of the first mounting areas 112 and the same one of the support arms 120 is within a preset distribution included angle range, which determines the possible setting angle of the vial 130, and further determines the adjustable angle of the swing arm 100, in this case, the same support arm 120 refers to the reference support arm 120 used as the reference among one or more support arms 120, and the included angles of the first mounting directions 113 of the first mounting areas 112 can be set according to the reference support arm 120. Meanwhile, the included angle of the first installation direction 113 adjacent to the first installation area 112 is within the preset interval included angle range, which determines the accuracy of the angle that the swing arm 100 can adjust.

In one embodiment, the included distribution angle ranges from 0 ° to 360 °, 0 ° to 90 °, 90 ° to 180 °, 180 ° to 270 °, or 270 ° to 360 °. The range of the interval included angle is 5-45 degrees, and besides, the range of the distribution included angle and the range of the interval included angle can also be other range values.

In one embodiment, at least one of the arms 120 includes a reference arm 120, the distribution included angle ranges from 0 ° to 360 °, the number of the first mounting regions 112 is 36, and the included angles between the first mounting directions 113 of adjacent first mounting regions 112 are 10 °, wherein the included angle between the first mounting direction 113 of one of the mounting regions and the reference arm 120 is 0 °, and at this time, the swing arm 100 can adjust 36 angles with an accuracy of every 10 °, and the torque sensor 200 is calibrated with this accuracy.

In another embodiment, at least one of the arms 120 includes a reference arm 120, the distribution angle ranges from 0 ° to 90 °, the number of the first mounting regions 112 is 4, the angles between the first mounting directions 113 of the 4 first mounting regions 112 and the reference arm 120 are 0 °, 30 °, 45 ° and 90 °, respectively, if the reference arm 120 refers to the arm 120 on the left side in fig. 1, the vial 130 may be disposed at a position within 90 ° around the upper left corner of the shaft hole 111, and the swing arm 100 is rotated to angles of 0 °, 30 °, 45 ° and 90 ° with respect to the horizontal state.

In another embodiment, at least one of the arms 120 includes a reference arm 120, the distribution angle is in a range of 90 ° to 180 °, the number of the first mounting regions 112 is 4, the angles between the first mounting directions 113 of the 4 first mounting regions 112 and the reference arm 120 are 90 °, 120 °, 135 ° and 180 °, respectively, if the reference arm 120 refers to the arm 120 on the left side in fig. 1, the vial 130 may be disposed at a position within 90 ° around the upper right corner of the shaft hole 111, and the swing arm 100 is rotated to an angle of 90 °, 120 °, 135 ° and 180 ° with respect to the horizontal.

In another embodiment, at least one of the arms 120 includes a reference arm 120, the distribution angle is 180 ° -270 °, the number of the first installation regions 112 is 4, the angles between the first installation directions 113 of the 4 first installation regions 112 and the reference arm 120 are 180 °, 210 °, 255 ° and 270 °, respectively, if the reference arm 120 refers to the arm 120 on the left side in fig. 1, the vial 130 may be located within 90 ° around the lower right corner of the shaft hole 111, and the swing arm 100 is rotated to the angles of 180 °, 210 °, 255 ° and 270 ° with respect to the horizontal state.

In another embodiment, at least one of the arms 120 includes a reference arm 120, the distribution angle ranges from 270 ° to 360 °, the number of the first mounting regions 112 is 4, the angles between the first mounting directions 113 of the 4 first mounting regions 112 and the reference arm 120 are 270 °, 300 °, 315 ° and 360 °, respectively, if the reference arm 120 refers to the arm 120 on the left side in fig. 1, the vial 130 may be disposed at a position within 90 ° of the lower left corner around the shaft hole 111, and the swing arm 100 is rotated to angles of 270 °, 300 °, 315 ° and 360 ° with respect to the horizontal state.

After the first mounting regions 112 are disposed in different directions around the pivot holes 111 (e.g., upper left, upper right, lower left, lower right as previously described), the vials 130 can be allowed to be mounted in different directions around the pivot holes 111, which can facilitate replacement of the first mounting regions 112 and vials 130 in different directions, increase the lifetime, and rotate the swing arm 100 clockwise or counterclockwise to a desired angle as desired.

However, the above angle ranges are only provided as partial examples, and those skilled in the art may set the number of the first mounting areas 112 and the interval angles according to actual requirements, so as to meet the calibration requirements of the specific torque sensor 200, which is not limited herein.

As for the specific form of the first mounting region 112, the first mounting region 112 is a mounting groove opened on the end surface of the fixing base 110, and the mounting groove is configured for mounting the level bubble 130 along the first mounting direction 113. The first mounting region 112 may also be an adhesive region provided at an end face of the mounting base 110, the adhesive region being configured for adhering vials 130 in the first mounting direction 113. The first mounting region 112 may also be a magnetically attractive area disposed on an end surface of the mounting base 110, and the magnetically attractive area is configured to magnetically mount the vial 130 along the first mounting direction 113. In addition, the first mounting area 112 may be a bayonet connection, a screw connection, or any other corresponding connection, which is not limited herein.

Referring to fig. 7 to 9, corresponding to the structure of the mounting groove, the swing arm 100 may be provided with a corresponding mounting groove at a desired angle, the accuracy of the position and the dimensional accuracy of the mounting grooves may be very high (0.01mm accuracy level) by machining, and after the mounting groove is formed, the level bubble 130 may be mounted in the mounting groove.

In one embodiment, the number of the arms 120 is 2, the included angle of 2 arms 120 is 180 °, at least one of the arms 120 is provided with at least one second mounting region 121, the second mounting region 121 has a second mounting direction 122, the second mounting direction 122 is parallel to the length direction of the arm 120, and the second mounting region 121 is configured to mount the vial 130 along the second mounting direction 122. At this time, in addition to the first mounting region 112, the second mounting region 121 also provides a position where the vial 130 can be mounted on the arm 120, and the second mounting region 121 and the second mounting direction 122 may have the same or different structures as the first mounting region 112 and the first mounting direction 113, so the technical contents of the first mounting region 112 and the first mounting direction 113 may be referred to, and the same contents are not repeated.

The second mounting area 121 serves as a structure for mounting the vial 130, and the second mounting area 121 may be disposed at any position on the swing arm 100, for example, the second mounting area 121 is located at one end of the arm 120 from which it is suspended, or the second mounting area 121 is located at a central position between both ends of the arm 120.

The first mounting region 112 and the second mounting region 121 serve as a structure for mounting the vials 130 and do not limit whether the vials 130 are actually mounted, but rather provide the possibility of being able to mount the vials 130. In actual use, the number and the installation positions of the vials 130 may be selected according to requirements, and the vials 130 may be installed in at least one of the first installation regions 112, or the vials 130 may be installed in all of the first installation regions 112, or the vials 130 may be installed in at least one of the second installation regions 121, or the vials 130 may be installed in all of the second installation regions 121. For example, only a single vial 130 may be used to switch between different first mounting areas 112 and second mounting areas 121.

Moreover, since the first mounting region 112 or the second mounting region 121 is a slotted mounting groove structure, it is not limited to the mounting groove being formed on the surface of the holder 110 or the arm 120, for example, the mounting groove may be formed inside the holder 110 or the arm 120, as long as the vial 130 can be mounted and dismounted in the mounting groove, and the corresponding portion of the holder 110 or the arm 120 corresponding to the mounting groove may also be formed with a transparent structure to read the reading of the vial 130.

Meanwhile, the specific shape of the first or second mounting

regions

112 or 121 may be set according to the shape of the vials 130 to be mounted, and is not limited to a regular or irregular shape including a rectangle, a square, etc., as long as the vials 130 can be stably and directionally accurately mounted.

When the leveling bubble 130 is installed on both the support arms 120, the leveling bubble 130 on both the support arms 120 can be used for mutual calibration, and the deformation of the swing arm 100 after load installation can be observed, so as to calculate the values of deflection, rigidity and the like.

For the calculation of the above-mentioned deflection and stiffness, the calculation method is as follows:

the swing arm 100 is simplified into a model as shown in fig. 12, a solid line in fig. 12 is an initial position of the swing arm 100, a dashed line in fig. 12 is a position where the swing arm 100 is deformed by a force, a deformation amount y is a deflection of the swing arm 100, and a stiffness k is defined as a moment required to be applied to generate a deformation amount per radian.

The value of the deflection y can be calculated from the reading of vial 130 and then based on the formula, assuming that vial 130 has a precision rating of a (in degrees/2 mm, i.e., the angle for each 2mm of bubble movement) and vial 130 has a reading of x (in mm) for the dashed line position in FIG. 12.

At this time, the deflection of the suspension end of the swing arm 100 is deformed

A rigidity of

When the rigidity of the swing arm 100 is very large (much higher than the rigidity of the harmonic reducer), the measured rigidity k can be regarded as the rigidity of the harmonic reducer, and when the rigidity of the swing arm 100 is very small (much lower than the rigidity of the harmonic reducer), the measured rigidity k can be regarded as the rigidity of the swing arm 100 itself.

In one embodiment, the support arm 120 is provided with a plurality of lifting portions 123 along the length direction thereof, the distances between adjacent lifting portions 123 are equal, and the lifting portions 123 are configured to be used for connecting loads. For example, the arm 120 may be 0.6m to 1.2m, such as 0.6m, 0.7m, 0.8m, 0.9m, 1m, 1.1m, 1.2m, etc., and then the distances between the adjacent lifting portions 123 are equal, so that the actual distance between the load and the fixing base 110 when the load is lifted at a certain lifting portion 123 can be calculated, and the distance is also the length of the actual moment arm. The hoisting part 123 may be a hoisting hole formed in the support arm 120, or an alternative structure such as a buckle structure or a threaded connection structure that can realize load connection, and is not limited herein.

Referring to fig. 10 and 11, the present invention further provides a torque sensor 200 calibration apparatus, including a bracket 300 and a swing arm 100, wherein the bracket 300 is configured to mount the torque sensor 200 to be calibrated, and a shaft hole 111 of the swing arm 100 is configured to connect to a transmission shaft of the torque sensor 200. Moment sensor 200 can include for stiff end and loose end, when needs calibration moment sensor 200, can with moment sensor 200's stiff end fixed connection on support 300, moment sensor 200's loose end can include the transmission shaft, and the transmission shaft can take place to rotate for moment sensor 200, and swing arm 100 installs promptly on moment sensor 200's transmission shaft to assemble with the transmission shaft through shaft hole 111. At this time, according to the calibration requirement, a desired level bubble 130 can be installed by means of the first installation region 112, and the angle of the swing arm 100 is adjusted by means of the level bubble 130, thereby performing calibration of the torque sensor 200. Since the detailed structure, functional principle and technical effect of the swing arm 100 are described in detail in the foregoing, detailed description thereof is omitted. Reference is made to the above description for any technical content related to the swing arm 100.

The invention also provides a torque sensor 200 calibration method, and according to the torque sensor 200 calibration device, the method comprises the following steps: mounting a torque sensor 200 to be calibrated between the bracket 300 and the swing arm 100; rotating the swing arm 100, rotating the swing arm 100 to a preset target angle by means of the level vial 130 located in the first mounting region 112, and connecting a load on the swing arm 100; the moment sensor 200 is used for acquiring a sensor moment value of the swing arm 100, calculating a theoretical moment value of the swing arm 100, and calculating a moment difference value between the sensor moment value and the theoretical moment. After the moment difference value is obtained, the moment difference value can be compared with a threshold value conveniently, and if the moment difference value is not within the threshold value, the moment measurement function of the moment sensor 200 is defective and needs to be overhauled. The threshold value represents the degree of stability of the operating state of the expected torque sensor 200, and may be defined according to the requirement.

In the detailed calibration method, the torque sensor 200 calibration method further includes the steps of: the method comprises the following steps: setting a plurality of target angles, and calculating the moment difference value under each target angle in sequence; step two: when all the moment difference values are within a preset threshold value, finishing calibration; step three: and when any one torque difference value is not within the preset threshold value, overhauling the torque sensor 200, and repeating the first step and the second step.

According to the first step and the second step, if the torque difference after comparison is within the threshold, the torque sensor 200 is in a qualified state, but once the torque difference measured by the swing arm 100 at any angle is not within the threshold, the working state of the torque sensor 200 at the angle is at least proved to be a non-qualified state, so that maintenance is required to be performed, and the torque sensor 200 is ensured to have a relatively stable working state. And recalibrating after maintenance until the torque sensor 200 is in a proper state under a plurality of preset target angles. Wherein servicing the torque sensor 200 may be understood as reworking the torque sensor 200, such as re-assembling components, re-commissioning, etc., so that the force sensor's defects are repaired.

It should be noted that the calibration method is suitable for manual calibration or automatic control calibration.

The invention further provides a torque sensor 200 calibration system, which comprises the torque sensor 200 calibration device and a processing unit, wherein the processing unit is configured to obtain a sensor torque value of the swing arm 100 measured by the torque sensor 200, calculate a theoretical torque value of the swing arm 100, calculate a torque difference value between the sensor torque value and the theoretical torque, and compare the torque difference value with a preset threshold value to generate a calibration result. At this time, according to the logic judgment, the processing unit may be used to automatically control calibration until the torque difference is compared with the preset threshold value, so as to obtain an intuitive calibration result, where the calibration result may at least include a qualified or unqualified result, or may also provide a subdivided result, such as a better state, a suboptimal state, a worse state, and the like, of the torque sensor 200 according to the setting of the threshold value, so as to embody the intelligence of the automatic control calibration, which is not limited herein.

In one embodiment, the processing unit comprises a first processor, a second processor, and a third processor, the first processor is configured to obtain a sensor torque value of the swing arm 100 measured by the torque sensor 200; the second processor is configured for calculating a theoretical moment value of the swing arm 100; the third processor is configured to calculate a torque difference value between the sensor torque value and the theoretical torque, and compare the torque difference value with a preset threshold value to generate a calibration result. The first processor, the second processor, and the third processor may optionally adopt a wired or wireless data transmission manner according to requirements, and are not limited herein. Meanwhile, a matched interaction unit can be arranged, and the interaction unit can be equipment such as a display and the like and is used for displaying necessary information such as data, prompt information, a calibration result and the like of the calibration process.

The invention also provides a robot calibration system, which is characterized by comprising the swing arm 100; alternatively, the torque sensor 200 calibrates the device; alternatively, the torque sensor 200 calibrates the system. Since the specific structures, functional principles and technical effects of the swing arm 100, the torque sensor 200 calibration device and the torque sensor 200 calibration system are described in detail in the foregoing, detailed description is omitted here. Reference is made to the above description for any technical contents relating to the swing arm 100, the torque sensor 200 calibration device, and the torque sensor 200 calibration system.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A swing arm for torque sensor calibration, the swing arm comprising:

2. The swing arm according to claim 1, wherein the included angle between the first installation direction of each first installation area and the same support arm is within a preset distribution included angle range; and/or the included angle of the first installation direction of the adjacent first installation area is within the range of the preset interval included angle.

3. The swing arm of claim 2 wherein the distribution included angle ranges from 0 ° -360 °, 0 ° -90 °, 90 ° -180 °, 180 ° -270 °, or 270 ° -360 °; and/or the included angle of the interval is in the range of 5-45 degrees.

4. The swing arm according to claim 3, wherein at least one of the support arms comprises a reference support arm, the distribution included angle ranges from 0 ° to 360 °, the number of the first mounting areas is 36, the included angles between the first mounting directions of the adjacent first mounting areas are 10 °, and the included angle between the first mounting direction of one of the mounting areas and the reference support arm is 0 °;

5. The swing arm of claim 1 wherein the first mounting area is a mounting slot opening in an end face of the mount, the mounting slot configured for mounting a vial in the first mounting direction;

6. The swing arm of any one of claims 1 to 5 wherein the number of arms is 2, the angle of 2 arms is 180 °, at least one of the arms is provided with at least one second mounting region having a second mounting direction parallel to the length of the arm, the second mounting region being configured for mounting a vial in the second mounting direction.

7. The swing arm of claim 6 wherein the second mounting area is located at an end of the suspension of the arm.

8. The swing arm of claim 6 wherein at least one of the first mounting regions has a level vial mounted therein; and/or a vial is mounted in at least one of the second mounting regions.

9. The swing arm of claim 6, wherein the support arm is provided with a plurality of hoisting parts along the length direction, the distance between every two adjacent hoisting parts is equal, and the hoisting parts are configured for connecting loads.

10. The swing arm of claim 9 wherein the sling is a hole drilled in the arm.

11. A torque sensor calibration device, comprising:

a bracket configured for mounting a torque sensor to be calibrated;

the swing arm according to any one of claims 1 to 10, wherein the shaft hole of the swing arm is configured for connecting a transmission shaft of the torque sensor.

12. A torque sensor calibration method, characterized in that the torque sensor calibration device according to claim 11, comprises the steps of:

13. The torque sensor calibration method according to claim 12, comprising the steps of:

14. A torque sensor calibration system, comprising:

the torque sensor calibration device of claim 11;

15. The torque sensor calibration system of claim 14, wherein the processing unit comprises:

16. A robot calibration system, comprising:

the swing arm of any one of claims 1 to 10; or,

the torque sensor calibration device of claim 11; or,

the torque sensor calibration system of claim 14 or 15.