CN116818072A - Method and device for determining load weight, storage medium and electronic device - Google Patents
Method and device for determining load weight, storage medium and electronic device Download PDFInfo
- Publication number
- CN116818072A CN116818072A CN202310800214.6A CN202310800214A CN116818072A CN 116818072 A CN116818072 A CN 116818072A CN 202310800214 A CN202310800214 A CN 202310800214A CN 116818072 A CN116818072 A CN 116818072A
- Authority
- CN
- China
- Prior art keywords
- curve
- target
- load
- weight
- determining
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 90
- 238000003860 storage Methods 0.000 title claims abstract description 17
- 238000006073 displacement reaction Methods 0.000 claims abstract description 161
- 230000007246 mechanism Effects 0.000 claims abstract description 106
- 230000008569 process Effects 0.000 claims abstract description 41
- 230000008859 change Effects 0.000 claims abstract description 31
- 238000010008 shearing Methods 0.000 claims abstract description 25
- 238000004590 computer program Methods 0.000 claims description 16
- 238000012545 processing Methods 0.000 claims description 9
- 230000004044 response Effects 0.000 claims description 7
- 238000005516 engineering process Methods 0.000 abstract description 7
- 230000006870 function Effects 0.000 description 16
- 238000005259 measurement Methods 0.000 description 13
- 239000000463 material Substances 0.000 description 12
- 238000010586 diagram Methods 0.000 description 11
- 230000033001 locomotion Effects 0.000 description 11
- 230000003287 optical effect Effects 0.000 description 11
- 230000005540 biological transmission Effects 0.000 description 6
- 238000004519 manufacturing process Methods 0.000 description 6
- 230000005484 gravity Effects 0.000 description 5
- 238000000691 measurement method Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 238000001125 extrusion Methods 0.000 description 3
- 230000001960 triggered effect Effects 0.000 description 3
- 230000009471 action Effects 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 238000011088 calibration curve Methods 0.000 description 2
- 238000004891 communication Methods 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 238000007689 inspection Methods 0.000 description 2
- 238000013178 mathematical model Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 238000005303 weighing Methods 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000000712 assembly Effects 0.000 description 1
- 238000000429 assembly Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 230000002146 bilateral effect Effects 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000010295 mobile communication Methods 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 229920001084 poly(chloroprene) Polymers 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
- B66F9/00—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
- B66F9/06—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
- B66F9/075—Constructional features or details
- B66F9/07504—Accessories, e.g. for towing, charging, locking
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
- B66F9/00—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
- B66F9/06—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
- B66F9/075—Constructional features or details
- B66F9/0755—Position control; Position detectors
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01G—WEIGHING
- G01G19/00—Weighing apparatus or methods adapted for special purposes not provided for in the preceding groups
- G01G19/08—Weighing apparatus or methods adapted for special purposes not provided for in the preceding groups for incorporation in vehicles
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01G—WEIGHING
- G01G19/00—Weighing apparatus or methods adapted for special purposes not provided for in the preceding groups
- G01G19/08—Weighing apparatus or methods adapted for special purposes not provided for in the preceding groups for incorporation in vehicles
- G01G19/083—Weighing apparatus or methods adapted for special purposes not provided for in the preceding groups for incorporation in vehicles lift truck scale
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01G—WEIGHING
- G01G3/00—Weighing apparatus characterised by the use of elastically-deformable members, e.g. spring balances
- G01G3/12—Weighing apparatus characterised by the use of elastically-deformable members, e.g. spring balances wherein the weighing element is in the form of a solid body stressed by pressure or tension during weighing
Landscapes
- Engineering & Computer Science (AREA)
- Transportation (AREA)
- Structural Engineering (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Civil Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Mechanical Engineering (AREA)
- Forklifts And Lifting Vehicles (AREA)
Abstract
The embodiment of the invention provides a method and a device for determining load weight, a storage medium and an electronic device, wherein the method comprises the following steps: controlling a fork shearing mechanism of the automatic guide vehicle to execute a first lifting operation; acquiring N pairs of displacement amounts in the first lifting operation process, and determining a target curve based on the N pairs of displacement amounts, wherein the N pairs of displacement amounts represent the horizontal displacement amounts of the screw rods and the vertical displacement amounts of the trays acquired at N moments, and the target curve represents the change relation between the horizontal displacement amounts of the screw rods and the vertical displacement amounts of the trays; and determining the weight of the target load according to the target curve and a preset M curve, wherein the M curves represent different change relations between the horizontal displacement of the screw rod and the vertical displacement of the tray in the first lifting operation process of the scissor mechanism when the tray is respectively loaded with M loads with known weights. The invention solves the technical problem of lower accuracy of determining the load weight in the related technology.
Description
Technical Field
The embodiment of the invention relates to the technical field of robots, in particular to a method and a device for determining load weight, a storage medium and an electronic device.
Background
Automatic guided vehicles (Automated Guided Vehicle, AGV) receive widespread attention from industrial manufacturing in the context of intelligent manufacturing and robotic replacement policies becoming widely accepted. AGV is the automatic travelling bogie that can replace the manual work to carry out intelligent transport, because of its characteristics that have degree of automation higher, unmanned transport have become intelligent transport equipment's important component to among wide application in industries such as storage, commodity circulation, improved production efficiency to a great extent, reduced manufacturing cost. In the process of carrying goods, in order to reasonably distribute the position of materials in a goods shelf, judge overload and increase the running stability of an AGV trolley, part of AGV trolleys start to increase the demand for measuring the weight of the materials. After the weight measurement function of the materials is realized, on one hand, the placement position of the heavy-load materials on a goods shelf can be optimized, and the stability of the goods shelf and the safety of taking and placing the materials are improved; on the other hand can make AGV dolly select the travel speed of matching load weight, increase transport efficiency and stability. The weight measurement function of the existing AGV trolley is often realized by adding a weight measurement sensor at a lifting mechanism or a tray, but the weight measurement mode can be influenced by the placement position of the weight measurement sensor, and if the placement position of a material is eccentric, errors are very easy to generate, and meanwhile, the design cost can be increased. It can be seen that the related art mainly relies on a weight measurement sensor to determine the load weight, but this method is prone to generate a large error, resulting in a low accuracy of the determined load weight.
Aiming at the technical problem of lower accuracy of determining the load capacity in the related art, no effective solution is proposed at present.
Disclosure of Invention
The embodiment of the invention provides a method and a device for determining load weight, a storage medium and an electronic device, which are used for at least solving the technical problem of lower accuracy of determining the load weight in the related technology.
According to an embodiment of the present invention, there is provided a method of determining a load weight, including: under the condition that a tray of the automatic guided vehicle is loaded with a target load, responding to a received first target instruction, controlling a fork shearing mechanism of the automatic guided vehicle to execute a first lifting operation, wherein the tray is arranged above the fork shearing mechanism, and the first lifting operation is used for controlling a screw rod in the automatic guided vehicle to move a first distance along a horizontal direction and driving the fork shearing mechanism to move a second distance along a vertical direction by the screw rod; acquiring N pairs of displacement amounts in the process of executing the first lifting operation, and determining a target curve based on the N pairs of displacement amounts, wherein the N pairs of displacement amounts are used for representing the horizontal displacement amounts of the screw rods and the vertical displacement amounts of the trays acquired at N moments in the process of executing the first lifting operation, N is a positive integer greater than or equal to 2, and the target curve represents a change relationship between the horizontal displacement amounts of the screw rods and the vertical displacement amounts of the trays in the process of controlling the scissor mechanism to execute the first lifting operation under the condition that the trays are loaded with the target load; and determining the weight of the target load according to the target curve and a preset M curve, wherein the M curves are used for representing different change relations between the horizontal displacement amount of the screw rod and the vertical displacement amount of the tray in the process of controlling the scissor mechanism to execute the first lifting operation under the condition that the tray is respectively loaded with M loads with known weights and different weights, and the different change relations are related to different deformations generated by the weights of the M loads on joint nodes in the scissor mechanism, and M is a positive integer greater than or equal to 2.
In an exemplary embodiment, the determining a target curve based on the N pairs of displacement amounts includes: obtaining a plurality of line segments based on the N pairs of displacement amounts, wherein the line segments are obtained by sequentially connecting coordinate points represented by each pair of displacement amounts in the N pairs of displacement amounts; fitting the line segments to obtain the target curve; or fitting coordinate points represented by each pair of displacement amounts in the N pairs of displacement amounts to obtain the target curve.
In one exemplary embodiment, before the controlling the scissor mechanism of the automated guided vehicle to perform the first lifting operation, the method further comprises: for an ith load in the M loads, executing the following operations to obtain an ith curve corresponding to the ith load, wherein i is a positive integer greater than or equal to 1 and less than or equal to M, and the M curves comprise the ith curve: controlling the scissor mechanism to execute the first lifting operation and acquire a P pair of displacement amounts in response to a received second target instruction when the tray is loaded with the ith load, wherein the P pair of displacement amounts are used for representing the horizontal displacement amounts of the screw rod and the vertical displacement amounts of the tray, which are acquired at P moments in the process of executing the first lifting operation and are in the case that the weight of the ith load generates the ith deformation on a joint node in the scissor mechanism, and P is a positive integer greater than or equal to 2; obtaining the ith curve based on the P pairs of displacement, wherein the ith curve corresponds to the weight of the ith load; and obtaining the M curves according to the ith curve.
In an exemplary embodiment, the determining the weight of the target load according to the target curve and a preset M curves includes: searching curves matched with the target curve in the M curves; and under the condition that the curve matched with the target curve is found, determining the weight of the target load according to the weight corresponding to the curve matched with the target curve.
In an exemplary embodiment, said searching for a curve matching the target curve among the M curves includes: the following operations are executed on each curve in the M curves respectively, wherein the each curve is a current curve when the following operations are executed: determining a first set of points on the current curve and a second set of points on the target curve, wherein the first set of points and the second set of points each comprise Q points, and the abscissa of the Q points in the first set of points is the same as the abscissa of the Q points in the second set of points, wherein Q is a positive integer greater than or equal to 1; determining differences between the ordinate of the Q points in the first set of points and the ordinate of the Q points in the second set of points, resulting in Q differences altogether; determining an average value or an accumulated value of the Q differences as a distance between the current curve and the target curve; determining that the current curve is a curve matched with the target curve under the condition that the distance between the current curve and the target curve is smaller than or equal to a preset threshold value; and determining that the current curve is not a curve matched with the target curve under the condition that the distance between the current curve and the target curve is larger than the preset threshold value.
In an exemplary embodiment, the determining the weight of the target load according to the weight corresponding to the curve matching the target curve includes: determining the weight corresponding to the curve matched with the target curve as the weight of the target load under the condition that one curve matched with the target curve is found; or under the condition that two adjacent curves matched with the target curve are found, weighting and summing weights corresponding to the two adjacent curves to obtain the weight of the target load.
In one exemplary embodiment, after said determining the weight of the target load, the method further comprises: and determining an operating parameter of the automatic guided vehicle according to the weight of the target load, wherein the operating parameter comprises the operating speed of the automatic guided vehicle.
According to another embodiment of the present invention, there is also provided a load weight determining apparatus including: the control module is used for responding to the received first target instruction under the condition that a tray of the automatic guiding vehicle is loaded with the target load, and controlling a fork shearing mechanism of the automatic guiding vehicle to execute a first lifting operation, wherein the tray is arranged above the fork shearing mechanism, and the first lifting operation is used for controlling a screw rod in the automatic guiding vehicle to move a first distance along the horizontal direction and driving the fork shearing mechanism to move a second distance along the vertical direction by the screw rod; a processing module configured to acquire N pairs of displacement amounts during execution of the first lifting operation, and determine a target curve based on the N pairs of displacement amounts, where the N pairs of displacement amounts are used to represent a horizontal displacement amount of the screw and a vertical displacement amount of the tray acquired at N times during execution of the first lifting operation, and N is a positive integer greater than or equal to 2, and the target curve represents a change relationship between the horizontal displacement amount of the screw and the vertical displacement amount of the tray during control of the scissor mechanism during execution of the first lifting operation in a case where the tray is loaded with the target load; the first determining module is configured to determine the weight of the target load according to the target curve and a preset M curves, where the M curves are used to represent different change relationships between the horizontal displacement amount of the screw rod and the vertical displacement amount of the tray in the process of controlling the scissor mechanism to execute the first lifting operation when the tray is loaded with M loads with known and different weights, and M is a positive integer greater than or equal to 2.
According to a further embodiment of the invention, there is also provided a computer readable storage medium having stored therein a computer program, wherein the computer program is arranged to perform the steps of any of the method embodiments described above when run.
According to a further embodiment of the invention, there is also provided an electronic device comprising a memory having stored therein a computer program and a processor arranged to run the computer program to perform the steps of any of the method embodiments described above.
According to the invention, when the tray of the automatic guided vehicle is loaded with a target load, the first lifting operation is controlled to be executed by the fork shearing mechanism of the automatic guided vehicle in response to a received first target instruction, wherein the first lifting operation is used for controlling the lead screw of the automatic guided vehicle to move a first distance along the horizontal direction and the fork shearing mechanism is driven by the lead screw to move a second distance along the vertical direction, N pairs of displacement amounts are obtained at N moments in the process of executing the first lifting operation, and a target curve is determined based on the N pairs of displacement amounts, namely a change relation curve between the horizontal displacement amount of the lead screw and the vertical displacement amount of the tray in the process of executing the first lifting operation by the fork shearing mechanism is determined under the condition that the tray is loaded with the target load; and then, determining the weight of the target load according to the target curve and a preset M curve, wherein the M curve represents different change relations between the horizontal displacement amount of the screw rod and the vertical displacement amount of the tray in the process of executing the first lifting operation by the scissor mechanism under the condition that the weight of each load in the M loads generates different deformations to the joint nodes in the scissor mechanism when the tray is respectively loaded with M loads with known different weights. The method for determining the weight of the load by mainly adopting the weight measuring sensor in the related technology is avoided, and the problem of larger error caused by the influence of the placement position of the weight measuring sensor and the gravity center offset or the load eccentricity is easily solved. Therefore, the technical problem of lower accuracy of determining the load weight in the related technology is solved, and the effect of improving the accuracy of determining the load weight is achieved.
Drawings
FIG. 1 is a block diagram of a mobile terminal hardware configuration of a method for determining a load weight according to an embodiment of the present invention;
FIG. 2 is a flow chart of a method of determining load weight according to an embodiment of the invention;
FIG. 3 is a schematic view of the AGV's carriage profile according to an embodiment of the present invention;
FIG. 4 is a schematic view of an AGV cart scissor assembly according to an embodiment of the invention;
FIG. 5 is a block diagram of an AGV control system according to an embodiment of the invention;
FIG. 6 is a flow chart of a load measurement method according to an embodiment of the invention;
FIG. 7 is a schematic diagram of theoretical lifting and lateral displacement variation of a scissor mechanism according to an embodiment of the invention;
FIG. 8 is a schematic diagram of actual lifting and lateral displacement variation of a scissor mechanism according to an embodiment of the invention;
FIG. 9 is a schematic diagram of a calibration function curve according to an embodiment of the invention;
fig. 10 is a block diagram of a load weight determining apparatus according to an embodiment of the present invention.
Detailed Description
Embodiments of the present invention will be described in detail below with reference to the accompanying drawings in conjunction with the embodiments.
It should be noted that the terms "first," "first," and the like in the description and the claims of the present invention and the above-described drawings are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order.
The method embodiments provided in the embodiments of the present application may be performed in a mobile terminal, a computer terminal or similar computing device. Taking the operation on a mobile terminal as an example, fig. 1 is a block diagram of a mobile terminal hardware structure of a method for determining a load weight according to an embodiment of the present application. As shown in fig. 1, a mobile terminal may include one or more (only one is shown in fig. 1) processors 102 (the processor 102 may include, but is not limited to, a microprocessor MCU or a processing device such as a programmable logic device FPGA) and a memory 104 for storing data, wherein the mobile terminal may also include a transmission device 106 for communication functions and an input-output device 108. It will be appreciated by those skilled in the art that the structure shown in fig. 1 is merely illustrative and not limiting of the structure of the mobile terminal described above. For example, the mobile terminal may also include more or fewer components than shown in fig. 1, or have a different configuration than shown in fig. 1.
The memory 104 may be used to store a computer program, for example, a software program of application software and a module, such as a computer program corresponding to a method for determining a load weight in an embodiment of the present application, and the processor 102 executes the computer program stored in the memory 104 to perform various functional applications and data processing, that is, to implement the above-described method. Memory 104 may include high-speed random access memory, and may also include non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, the memory 104 may further include memory remotely located relative to the processor 102, which may be connected to the mobile terminal via a network. Examples of such networks include, but are not limited to, the internet, intranets, local area networks, mobile communication networks, and combinations thereof.
The transmission device 106 is used to receive or transmit data via a network. Specific examples of the network described above may include a wireless network provided by a communication provider of the mobile terminal. In one example, the transmission device 106 includes a network adapter (Network Interface Controller, simply referred to as NIC) that can connect to other network devices through a base station to communicate with the internet. In one example, the transmission device 106 may be a Radio Frequency (RF) module, which is configured to communicate with the internet wirelessly.
In this embodiment, a method for determining a load weight is provided, and fig. 2 is a flowchart of a method for determining a load weight according to an embodiment of the present invention, as shown in fig. 2, where the flowchart includes the following steps:
step S202, under the condition that a tray of an automatic guiding vehicle is loaded with a target load, responding to a received first target instruction, controlling a fork mechanism of the automatic guiding vehicle to execute a first lifting operation, wherein the tray is arranged above the fork mechanism, and the first lifting operation is used for controlling a screw rod in the automatic guiding vehicle to move a first distance along a horizontal direction and driving the fork mechanism to move a second distance along a vertical direction by the screw rod;
Step S204, acquiring N pairs of displacement amounts in the process of executing the first lifting operation, and determining a target curve based on the N pairs of displacement amounts, wherein the N pairs of displacement amounts are used for representing the horizontal displacement amounts of the screw rods and the vertical displacement amounts of the trays acquired at N moments in the process of executing the first lifting operation, N is a positive integer greater than or equal to 2, and the target curve represents a change relation between the horizontal displacement amounts of the screw rods and the vertical displacement amounts of the trays in the process of controlling the scissor mechanism to execute the first lifting operation under the condition that the trays are loaded with the target load;
and S206, determining the weight of the target load according to the target curve and a preset M curves, wherein the M curves are used for representing different change relations between the horizontal displacement amount of the screw rod and the vertical displacement amount of the tray in the process of controlling the scissor mechanism to execute the first lifting operation under the condition that the tray is respectively loaded with M loads with known and different weights, and M is a positive integer greater than or equal to 2.
Through the steps, when the tray of the automatic guided vehicle is loaded with the target load, the scissor mechanism of the automatic guided vehicle is controlled to execute a first lifting operation in response to a received first target instruction, wherein the first lifting operation is used for controlling the screw rod of the automatic guided vehicle to move a first distance along the horizontal direction and the screw rod drives the scissor mechanism to move a second distance along the vertical direction, N pairs of displacement amounts are obtained at N moments in the process of executing the first lifting operation, and a target curve is determined based on the N pairs of displacement amounts, namely a change relation curve between the horizontal displacement amount of the screw rod and the vertical displacement amount of the tray in the process of executing the first lifting operation of the scissor mechanism is determined under the condition that the tray is loaded with the target load; and then, determining the weight of the target load according to the target curve and a preset M curve, wherein the M curve represents different change relations between the horizontal displacement amount of the screw rod and the vertical displacement amount of the tray in the process of executing the first lifting operation by the scissor mechanism under the condition that the weight of each load in the M loads generates different deformations to the joint nodes in the scissor mechanism when the tray is respectively loaded with M loads with known different weights. The method for determining the weight of the load by mainly adopting the weight measuring sensor in the related technology is avoided, and the problem of larger error caused by the influence of the placement position of the weight measuring sensor and the gravity center offset or the load eccentricity is easily solved. Therefore, the technical problem of lower accuracy of determining the load weight in the related technology is solved, and the effect of improving the accuracy of determining the load weight is achieved.
The main execution body of the above steps may be a processor, or a controller, for example, a controller provided in an automatic guided vehicle, or a processor provided on a storage device and having man-machine interaction capability, or a processing device or a processing unit having similar processing capability, but is not limited thereto.
In the solution provided in step S202, the target load may be a load or a material, for example, the weight of the target load is now determined, where the conventional method is to determine the weight of the target load by using a weight measurement sensor disposed on an automatic guided vehicle (or called an AGV), but the conventional method is easily affected by the placement position of the weight measurement sensor and the center of gravity of the load or the eccentricity of the load, so that the error is large, and in the method in this embodiment, the target load is placed in a tray of the AGV, where the tray is disposed above a fork mechanism of the AGV, and when a first target command is received, the fork mechanism of the AGV is controlled to perform a first lifting operation, for example, the first target command may be sent by a controller or a motherboard in the AGV, or by remote control, where the first lifting operation may be to control a lead screw in the AGV to move a first distance, for example, 20cm or other distances, and the lead screw drives the fork mechanism to move a second distance in the vertical direction, and in fact, when the lead screw moves horizontally, the node of the fork mechanism also moves horizontally; alternatively, the first lifting operation may be only moved in one direction, for example, only lifting (or lifting) is performed, or only lowering is performed, or may be performed by first lifting a distance and then lowering a distance, or by first lowering a distance and then lifting a distance, and the specific first lifting operation may be set according to actual needs.
In the method for measuring the load weight in the embodiment of the application, a scissor type AGV is taken as an application example, and fig. 3 is a schematic view of the appearance of the AGV according to the embodiment of the application, wherein the scissor type AGV mainly comprises a chassis assembly 200 and a lifting assembly 100. The lifting assembly 100 (or referred to as a scissor assembly) mainly comprises a tray 1, an outer connecting rod 2, an optical axis 3, an inner connecting rod 4, a lifting motor 5, an optical axis support 6, a horizontal stay wire encoder 7, a motor bracket 8, an upper sliding rail assembly 9, a limit sensor 10, a lower sliding rail assembly 11, a limit piece 12, an adapter plate 13, a ball screw 14, a screw support 15, a linear guide rail 16 and a vertical stay wire encoder 17, as shown in fig. 4.
The tray 1 is a steel plate with neoprene covered on the upper surface, is arranged above the scissor mechanism and is mainly used for placing a charging basket or lifting a goods shelf; the total number of the outer connecting rods 2 is four, and the outer connecting rods are assembled with the inner connecting rods 4 through the optical axis 3 and are mainly used for converting horizontal movement into vertical movement; the optical axes 3 are 5 in number, and are fixed between the connecting rods through a left end and a right end respectively, and are mainly used for combining the inner connecting rod and the outer connecting rod together; the two inner connecting rods 4 are assembled with the outer connecting rod 2 through the optical axis 3, and are mainly used for converting horizontal motion into vertical motion; the lifting motor 5 is a speed reduction integrated machine, is arranged on a motor bracket through a screw on a flange surface, is connected with the ball screw 14 through a coupler, and is mainly used for outputting power to the ball screw; the optical axis supports 6 are totally two and are respectively fixed on the outer sides of the connecting rods at the fixed side of the lifting assembly through clamp springs, and are mainly used for fixing and supporting the connecting rod mechanisms; the horizontal stay wire encoder 7 is fixed on the chassis, and the stay wire output end is connected with the side surface of the screw rod sliding block and used for detecting the horizontal displacement of the screw rod nut; the motor bracket 8 is fixed on the chassis assembly through screws and is mainly used for supporting the lifting motor; the upper slide rail assemblies 9 are two groups in total and are fixed below the tray through screws and are mainly used for sliding on the moving side above the connecting rod; the limit sensors 10 are totally two, are fixed on the lower slide rail assembly 11 through screws, trigger limit signals when the limit pieces are close, and transmit the limit signals to the main board; the lower sliding rail assembly 11 is fixed on the chassis assembly through screws and is mainly used for sliding on the moving side below the connecting rod; the limiting piece 12 is fixed in the clamping groove of the lower sliding rail assembly through the optical axis, can move back and forth in the clamping groove along with the optical axis, and triggers a limiting signal at a specific position; the adapter plate 13 connects the optical axis of the moving side of the connecting rod with the ball screw 14 through a screw, and the lower end of the adapter plate is connected with a slide block of the linear guide rail and is mainly used for transmitting the motion of the ball screw to the scissor mechanism; one end of the ball screw 14 is connected with the lifting motor 5 through a coupler, and the other end of the ball screw is connected with the connecting rod assembly through an adapter plate and is mainly used for converting lifting rotary motion into linear motion and transmitting the linear motion to the shearing fork mechanism; the screw rod support 15 is fixed on the chassis assembly through screws and is mainly used for supporting one end of the ball screw rod 14; the linear guide rail 16 is fixed on the chassis through a screw, and a sliding block of the linear guide rail is connected with the adapter plate and is mainly used for providing supporting force for the scissor assembly; the vertical stay wire encoder 17 is fixed on the chassis, and the stay wire output end is connected with the bottom of the tray and used for detecting the vertical displacement of the tray.
In the technical solution provided in the step S204, N pairs of displacement amounts may be obtained during the first lifting operation performed by the scissor mechanism, where N pairs of displacement amounts refer to a horizontal displacement amount of a screw rod and a vertical displacement amount of a tray, which are collected at N times during the first lifting operation performed, in practical application, the value of N may be set as required, for example, 20 (or 50, or other values) pairs of displacement amounts may be collected, and in combination with fig. 4, the horizontal displacement amount of the screw rod may be detected by the horizontal wire encoder 7, and the vertical displacement amount of the tray may be detected by the vertical wire encoder 17; and then determining a target curve according to the N pairs of displacement amounts, wherein the target curve is used for representing a change relation curve between the horizontal displacement amount of the screw rod and the vertical displacement amount of the tray in the process of executing the first lifting operation by the shearing fork mechanism when the tray is provided with the target load, for example, fitting by using a least square method according to N coordinate points corresponding to the N pairs of displacement amounts to obtain a target curve, or fitting a plurality of line segments, such as N-1 line segments, according to the N pairs of displacement amounts to obtain a target curve, wherein the obtained target curve is a smooth curve, and the change relation between the horizontal displacement amount and the vertical displacement amount of the shearing fork mechanism in the process of executing the first lifting operation can be seen from the target curve.
In the technical solution provided in step S206, the preset M curves may be predetermined curves corresponding to loads of M known weights, where the M curves represent M curves corresponding to loads of M known weights when the tray is loaded with different loads of M loads respectively, and different change relationships between the horizontal displacement amount of the screw rod and the vertical displacement amount of the tray during the first lifting operation are performed by controlling the scissor mechanism, where the different change relationships are obtained when different deformations of the joint nodes in the scissor mechanism are caused by the weights of the respective loads of the M loads, the joint nodes may be connection nodes between the scissor mechanism and the tray, or may be connection nodes between an outer link (e.g. the outer link 2 in fig. 4) and an inner link (e.g. the outer link 4 in fig. 4), so that the M curves corresponding to loads of M known weights may be obtained in advance, and thus, for example, whether there is a target load matching curve found in the M curves, and if there is a target load matching curve, the j may be determined that the target load matching curve is found in the M curves, and if there is a load matching the target load matching curve j. In this embodiment, by determining the target curve when the scissor mechanism executes the first lifting operation when the tray is loaded with the target load and combining the M curves corresponding to the M loads with known weights, the weight of the target load can be determined, so that the problem that the error is large due to the influence of the placement position of the weight measuring sensor and the load gravity center offset or the load eccentricity caused by the method of mainly adopting the weight measuring sensor to determine the weight of the load in the related art is avoided, and the purpose of saving the cost of the weight measuring sensor can be realized. Therefore, the technical problem of lower accuracy of determining the load weight in the related technology is solved, and the effect of improving the accuracy of determining the load weight is achieved.
In an alternative embodiment, the determining the target curve based on the N pairs of displacement amounts includes: obtaining a plurality of line segments based on the N pairs of displacement amounts, wherein the line segments are obtained by sequentially connecting coordinate points represented by each pair of displacement amounts in the N pairs of displacement amounts; fitting the line segments to obtain the target curve; or fitting coordinate points represented by each pair of displacement amounts in the N pairs of displacement amounts to obtain the target curve. In this embodiment, a plurality of line segments may be obtained based on N coordinate points corresponding to N pairs of displacement amounts, for example, N-1 line segments are obtained, and then the plurality of line segments are fitted to obtain a target curve; optionally, N coordinate points corresponding to the N pairs of displacement amounts may be fitted to obtain a target curve, for example, the N coordinate points may be fitted by using a least square method to obtain a smoother target curve. Through the embodiment, the purpose of obtaining the target curve based on the obtained N pairs of displacement is achieved.
In an alternative embodiment, before the controlling the scissor mechanism of the automated guided vehicle to perform the first lifting operation, the method further comprises: for an ith load in the M loads, executing the following operations to obtain an ith curve corresponding to the ith load, wherein i is a positive integer greater than or equal to 1 and less than or equal to M, and the M curves comprise the ith curve: controlling the scissor mechanism to execute the first lifting operation and acquire a P pair of displacement amounts in response to a received second target instruction when the tray is loaded with the ith load, wherein the P pair of displacement amounts are used for representing the horizontal displacement amounts of the screw rod and the vertical displacement amounts of the tray, which are acquired at P moments in the process of executing the first lifting operation and are in the case that the weight of the ith load generates the ith deformation on a joint node in the scissor mechanism, and P is a positive integer greater than or equal to 2; obtaining the ith curve based on the P pairs of displacement, wherein the ith curve corresponds to the weight of the ith load; and obtaining the M curves according to the ith curve. In this embodiment, for any one of M loads, such as the ith load, the above operation is performed to obtain an ith curve corresponding to the ith load, where the above operation includes controlling the scissors mechanism to perform the above first lifting operation when the ith load is loaded on the tray, and obtaining a P pair of displacement amounts, where P may be greater than N or less than N, which is not limited in this respect, and in practical application, where the placement of loads of different weights in the tray may generate different deformations to the joint node in the scissors mechanism, for example, the weight of the ith load generates a deformation in the ith to the joint node in the scissors mechanism, where the P pair of displacement amounts are obtained when the deformation is generated, and the ith curve may be obtained based on the P pair of displacement amounts; and the curves corresponding to other loads in the M loads can be obtained by analogy, so that the preset M curves can be obtained. In practical applications, the above operation process may be referred to as a calibration process, i.e. using loads of known weights to detect respectively to obtain corresponding calibration curves.
In an alternative embodiment, the determining the weight of the target load according to the target curve and the preset M curves includes: searching curves matched with the target curve in the M curves; and under the condition that the curve matched with the target curve is found, determining the weight of the target load according to the weight corresponding to the curve matched with the target curve. In this embodiment, a curve matching the target curve may be found in the M curves, and when it is found that there is a curve matching the target curve, the weight of the target load may be determined according to the weight corresponding to the curve matching the target curve, in practical application, one or more curves may exist in the M curves and match the target curve, for example, when there is a curve (such as a j-th curve) matching the target curve, the weight of the load (such as a j-th load in the M loads) corresponding to the j-th curve is determined as the weight of the target load; alternatively, when there are two curves (e.g., the kth and the (r) th curves) that match the target curve, the weight of the target load may be determined by combining the weight corresponding to the kth curve (e.g., the kth load of the M loads) and the weight corresponding to the (r) th curve (e.g., the (r) th load of the M loads). In the process of searching whether each curve in the M curves is matched with the target curve, the determination can be performed through the error or the distance between each curve and the target curve, for example, a plurality of points can be selected from the two curves, and the difference between the points before the ordinate is the same as the abscissa is compared to determine the error or the distance between the two curves. By the embodiment, the aim of determining the weight of the target load by comparing the target curve with the preset M curves is fulfilled.
In an alternative embodiment, said searching for a curve matching the target curve among the M curves includes: the following operations are executed on each curve in the M curves respectively, wherein the each curve is a current curve when the following operations are executed: determining a first set of points on the current curve and a second set of points on the target curve, wherein the first set of points and the second set of points each comprise Q points, and the abscissa of the Q points in the first set of points is the same as the abscissa of the Q points in the second set of points, wherein Q is a positive integer greater than or equal to 1; determining differences between the ordinate of the Q points in the first set of points and the ordinate of the Q points in the second set of points, resulting in Q differences altogether; determining an average value or an accumulated value of the Q differences as a distance between the current curve and the target curve; determining that the current curve is a curve matched with the target curve under the condition that the distance between the current curve and the target curve is smaller than or equal to a preset threshold value; and determining that the current curve is not a curve matched with the target curve under the condition that the distance between the current curve and the target curve is larger than the preset threshold value. In this embodiment, the difference between the ordinate of the Q points in the current curve and the ordinate of the Q points in the target curve may be obtained by comparing the difference between the abscissa of the Q points in the current curve and the ordinate of the Q points in the target curve in the case where the abscissa of the Q points in the current curve is the same, and then the distance between the current curve and the target curve is determined according to the Q differences, for example, the average value of the Q differences may be used as the distance between the two curves (i.e., the current curve and the target curve), or the accumulated value (or accumulated value) of the Q differences may be used as the distance between the two curves; when the distance between the two curves is less than or equal to a preset threshold, it may be determined that the current curve and the target curve are matched, and when the distance between the two curves is greater than the preset threshold, it may be determined that the current curve and the target curve are not matched. By the embodiment, the purpose of searching whether the curve matched with the target curve exists in the M curves is achieved.
In an alternative embodiment, the determining the weight of the target load according to the weight corresponding to the curve matching the target curve includes: determining the weight corresponding to the curve matched with the target curve as the weight of the target load under the condition that one curve matched with the target curve is found; or under the condition that two adjacent curves matched with the target curve are found, weighting and summing weights corresponding to the two adjacent curves to obtain the weight of the target load. In this embodiment, when it is found that one curve (for example, a jth curve) in the M curves matches the target curve, the weight of the load corresponding to the jth curve may be determined as the weight of the target load; or when two curves (such as a kth curve and a kth curve) in the M curves are found to be matched with the target curve, the weight of the target load can be determined by combining the weight (such as Qk) corresponding to the kth curve and the weight (such as Qr) corresponding to the kth curve, for example, the Qk and the Qr are subjected to weighted summation to obtain the weight of the target load, and when the weighted summation is performed, the weighted coefficient can be determined according to the distance between the target curve and the kth curve and the distance between the target curve and the kth curve; alternatively, the weighting coefficient may be set according to the distance between the target curve and the kth curve, the weight of the kth load, and the weight of the kth load. By the embodiment, the aim of determining the weight of the target load under the condition that the curve matched with the target curve is found is fulfilled.
In an alternative embodiment, after said determining the weight of the target load, the method further comprises: and determining an operating parameter of the automatic guided vehicle according to the weight of the target load, wherein the operating parameter comprises the operating speed of the automatic guided vehicle. In this embodiment, after determining the weight of the target load, for example, after determining the weight of the load or the material currently loaded by the AGV, further, the operation parameters of the AGV trolley may be optimized according to the determined weight of the target load, the optimal storage shelf position may be allocated to the target load according to the determined weight of the target load, and the optimal operation speed may be set for the AGV according to the weight of the target load, so that the operation speed may be maximized on the premise of ensuring no rollover, thereby improving the production and warehouse management efficiency.
It will be apparent that the embodiments described above are merely some, but not all, embodiments of the application. The present application will be specifically described with reference to examples.
Aiming at the problem that an additional weight measuring sensor is easily influenced by the eccentricity of a cargo position in the load measuring process of an AGV, the embodiment of the application provides a load measuring method based on a lifting curve of a scissor mechanism, firstly, a model among variables such as different load weights, joint deformation and lifting heights is established based on a multi-joint mechanical principle and stress analysis of the scissor mechanism, and a lifting motion curve under different loads is obtained; secondly, setting a horizontal stay wire encoder and a vertical stay wire encoder, collecting the horizontal displacement and the vertical displacement of the scissor mechanism in real time, and determining correction coefficients corresponding to different load weights in a lifting motion curve of the scissor mechanism through multi-load calibration; and finally, comparing an actual lifting change curve with a calibration value in the use process, and determining a corresponding lifting curve change coefficient, so that the load weight is determined, real-time data is provided for an anti-overturning algorithm, the motion stability of the vehicle body is improved, the influence of material eccentricity on a weight measurement result is reduced, the weight measurement accuracy of the material is improved, and meanwhile, the use cost of a weight measurement sensor is reduced.
In order to better explain the working steps of a load measuring method based on a lifting curve of a scissor mechanism, the working steps are explained with reference to a system composition diagram of fig. 5 and a flow chart of the measuring method of fig. 6.
FIG. 5 is a diagram of the components of an AGV control system according to an embodiment of the invention, which essentially comprises: the lifting device comprises a main board, a driver, a lifting motor, a screw rod, a fork shearing mechanism, a tray, a photoelectric limit sensor, a horizontal stay wire encoder and a vertical stay wire encoder, wherein the main board is used for sending control parameters (or commands) to the driver, the driver drives the lifting motor to work, so that the lifting mechanism (or the fork shearing mechanism) can perform lifting or descending operation, and the photoelectric limit sensor is used for monitoring whether the lifting mechanism triggers an upper limit signal in the lifting process; the stay wire output end of the horizontal stay wire encoder is connected with the side surface of the screw rod sliding block and used for detecting the horizontal displacement of the screw rod nut, namely, collecting horizontal displacement data, and the stay wire output end of the vertical stay wire encoder is connected with the bottom of the tray and used for detecting the vertical displacement of the tray, namely, collecting vertical displacement data.
Fig. 6 is a flow chart of a load measurement method according to an embodiment of the invention, the flow comprising:
S602, starting;
s604, calibrating: before starting to enter into work, standard load (corresponding to the M loads) calibration is required to be carried out on the AGV;
s606, placing a standard weight: standard weights with standard unit mass are placed on a tray of the AGV trolley; standard loads with different masses (or weights) can be calibrated by continuously increasing standard weights;
s608, self-checking: after goods or a material frame or a standard load is placed on a lifting tray, a photoelectric sensor (or a photoelectric limit sensor) below the tray detects that a distance signal changes, and the picking success is judged, a main board starts to send a self-checking command (corresponding to the second target command) to a lifting driver, firstly, a lifting mechanism lifts upwards for a certain distance, if the upper limit signal is not triggered, the lifting mechanism is ready to rotate reversely after lifting for a specified distance, if the upper limit signal is triggered, the lifting motor stops to rotate reversely immediately, the output current of the driver is detected in real time in the forward rotation process of the lifting motor, if the output current does not exceed a safety value, the operation is continued, otherwise, the overload fault of the lifting motor is reported, and the self-checking command is stopped; then the driver sends out a reverse driving signal, the lifting mechanism starts to descend downwards, the self-checking action is stopped after the lower limit signal is triggered, the output current of the driver is detected in real time in the same lifting motor reverse transmission process, if the output current does not exceed a safety value, the operation is continued, otherwise, the overload fault of the lifting motor is reported, and the self-checking command is stopped;
S610, detecting displacement by a double-stay wire encoder: during the self-inspection of the lifting motor, the horizontal and vertical stay wire encoders start to detect displacement variation (corresponding to the aforementioned N pairs of displacement or P pairs of displacement) in real time;
s612, calculating a lifting change curve (corresponding to each of the M curves): after a lifting change curve under the condition of load is acquired, a mathematical model established according to the invention is utilized to calculate a curvature coefficient A and a zero drift coefficient B of a lifting function in the model by utilizing least square fitting;
s614, judging whether the weight is larger than the full scale range, namely judging whether the weight of the standard load exceeds the full scale range;
if the judgment result is negative, returning to the step S606, and continuing to increase the standard weight with unit mass for calibration; if yes, go to step S616; that is, if the weight of the calibration is greater than the measurement maximum value, ending the calibration to enter a task mode, otherwise continuing to circulate steps S606-S612;
s616, calibration is completed.
S618, entering a task mode: after the calibration action is completed, the AGV formally enters a working mode, and can accept the instruction issued by the platform;
s620, running to a specified position to butt-joint materials: after the AGVs pass through the carrying nodes, the logistics system places cargoes on a tray of the AGV trolley through a mechanical arm or a conveyor belt, and then the AGV trolley starts to carry out self-inspection on loads;
S622, self-checking command: after the AGV detects the goods, starting to execute a self-checking instruction (corresponding to the first target instruction);
s624, calculating the load weight according to the lifting model: after the on-load self-test, matching the closest calibration model according to an actual load lifting curve acquired by the double-pull-wire encoder to obtain a corresponding load weight;
s626, provide data to the following algorithm: the calculated load weight can be used for an optimization algorithm of the vehicle body operation parameters;
s628, calculating an optimal cargo placement position: the optimal storage shelf position can be allocated according to the load weight;
s630, calculating the most efficient and stable running speed: the maximum running speed can be set on the premise of ensuring that the vehicle is not overturned according to the weight of the load, so that the production efficiency is improved;
s632, finishing, completing the task instruction and entering an idle mode.
It should be noted that, the steps S602-S616 are not necessarily executed each time, for example, only the calibration operation is performed when the AGV is first put into use, and the calibration curves corresponding to all the standard loads are recorded, and optionally, the calibration operation may be performed on the AGV every other period; after the AGV finishes the calibration operation, the AGV can be directly put into use and can be directly used for determining the weight of the load to be measured, namely, in the subsequent process of carrying and determining the weight each time, only the operation after the step S616 is needed to be executed.
The original shear fork mechanism stress analysis based on virtual displacement does not consider the joint deformation, but the actual process exists, so the joint deformation is introduced when the shear fork mechanism stress equation is constructed.
The two-stage shearing fork mechanism used in the embodiment of the application has a bilateral symmetry structure, and can be considered that the stress of each node has symmetry, and the number of the shearing fork mechanism and the tray are 4, so that the stress of each node is one fourth of the load, and according to the virtual displacement principle:wherein Q represents the load weight, F represents the lead screw thrust, dy 0 Representing virtual displacement in the vertical direction，dx 0 Representing a virtual displacement in the horizontal direction. Expressing load Q as with other variables, yields: />Wherein dy 0 /dx 0 It can be considered as the curvature k of the lifting curve. A link between the lift height and the horizontal displacement can thus be established: y is 1 ＝x 1 tanθ 1 As shown in FIG. 7, wherein x 1 Represents the transverse displacement of a theoretical shearing fork mechanism, y 1 (corresponding to h in FIG. 7) 1 ) Represents the lifting height theta of a theoretical shearing fork mechanism 1 Indicating the angles between the theoretical scissor links and the horizontal plane (not shown in fig. 7), P11 (P12), P21, P31 (P32), P41, P51 (P52) indicate the articulation nodes of the scissor, and iota is the length of the outer links.
In the actual operation process, under the condition of load compression, as in fig. 8, under the extrusion of the gravity Ga of the load, the joint point of the scissor mechanism can generate deformation errors and dislocation errors due to stress, and the relation between the actual lifting height and the horizontal displacement is as follows: y is 2 ＝x 2 tanθ 2 Wherein x is 2 Represents the actual transverse displacement of the scissor mechanism, y 2 (corresponding to h in FIG. 8) 2 ) Represents the actual lifting height of the scissor mechanism, theta 2 Indicating the actual angle of the scissor linkage to the horizontal (not shown in fig. 8). As shown in fig. 8, by analyzing the structure of the two-stage scissor mechanism, the actual scissor mechanism lifts by a height h 2 Lifting height h relative to theoretical scissor mechanism 1 The errors mainly occur in the deformation errors and dislocation errors of five joints P11 (P12), P21, P31 (P32), P41, P51 (P52) (corresponding to the joints P '11, P'12, P '21, P'31, P '32, P'41, P '51, P'52 after deformation in fig. 8), which can be expressed as: y is 2 ＝y 1 -5 (δ+ζ), wherein δ represents the deformation error of a single node and ζ represents the misalignment error of a single node. The same actual transverse displacement x of the scissor mechanism 2 Relative to the theoretical shear fork mechanism transverse displacement x 1 The error mainly arises from the variation of two points P51, P52 (corresponding to P '51, P'52 in FIG. 8) Shape errors and misalignment errors, which can be expressed as: x is x 2 ＝x 1 +2 (delta+ζ). The angle theta of the actual scissor mechanism after being extruded by the load 2 Can generate change due to joint point clearance and extrusion, and the angle theta between the joint point clearance and the extrusion and the theoretical angle theta 1 The relationship of (2) is as follows:the simplification is as follows: />It is displayed:
expressed in a form related to the basis function tan θ: y is 1 ＝Ax 1 +B, whereRepresenting the curvature coefficient of the actual lifting function,indicating the zero drift coefficient of the actual lifting function. Thus, after the lifting function slope k is obtained, the load Q is expressed in a form related to the lifting function curve k:the curvature coefficient A and the zero-shift coefficient B of the actual lifting function can be obtained by fitting displacement data collected in the self-checking process, and then performing a dichotomy difference with the calibration function Q (m) =f { A, B }, namely, matching with the calibration model (or calibration function), wherein FIG. 9 is a schematic diagram of a calibration function curve according to an embodiment of the application, and FIG. 9A 1 、A 2 、A 3 And determining the calibration function closest to the actual lifting function for curvature coefficients corresponding to loads with different weights respectively, so as to obtain the actual load mass m and the actual load weight Q.
The embodiment of the application has the following beneficial effects: 1) Compared with the traditional AGV which measures the load by adding a weight measuring sensor, the application can measure the weight of the load based on the change trend of the scissor mechanism, reduce the sensor setting and save the related cost; 2) Compared with the traditional AGV weight measurement method, the method has the advantages that on the basis of analyzing the stress condition of the scissor mechanism, a multi-joint clearance variable is introduced, a mathematical model of lifting load and lifting change curve is established, and a theoretical basis is provided for a load measurement method; 3) Compared with the traditional AGV weighing method, the single-point slope is utilized for weighing, standard weight calibration is carried out in advance, the load weight is determined based on the curvature change of the lifting curve, the calculated amount can be remarkably reduced, and the measurement accuracy can be improved.
From the description of the above embodiments, it will be clear to a person skilled in the art that the method according to the above embodiments may be implemented by means of software plus the necessary general hardware platform, but of course also by means of hardware, but in many cases the former is a preferred embodiment. Based on such understanding, the technical solution of the present invention may be embodied essentially or in a part contributing to the prior art in the form of a software product stored in a storage medium (e.g. ROM/RAM, magnetic disk, optical disk) comprising instructions for causing a terminal device (which may be a mobile phone, a computer, a server, or a network device, etc.) to perform the method according to the embodiments of the present invention.
There is also provided in this embodiment a load weight determining apparatus, fig. 10 is a block diagram of a load weight determining apparatus according to an embodiment of the present invention, as shown in fig. 10, including:
the control module 1002 is configured to, in case that a tray of the automatic guided vehicle is loaded with a target load, control a fork mechanism of the automatic guided vehicle to perform a first lifting operation in response to a received first target instruction, where the tray is disposed above the fork mechanism, and the first lifting operation is configured to control a screw in the automatic guided vehicle to move a first distance in a horizontal direction and drive the fork mechanism to move a second distance in a vertical direction by the screw;
A processing module 1004, configured to acquire N pairs of displacement amounts during execution of the first lifting operation, and determine a target curve based on the N pairs of displacement amounts, where the N pairs of displacement amounts are used to represent a horizontal displacement amount of the screw and a vertical displacement amount of the tray acquired at N times during execution of the first lifting operation, and N is a positive integer greater than or equal to 2, and the target curve represents a change relationship between the horizontal displacement amount of the screw and the vertical displacement amount of the tray during control of the scissor mechanism to execute the first lifting operation when the tray is loaded with the target load;
a first determining module 1006, configured to determine the weight of the target load according to the target curve and a preset M curves, where the M curves are used to represent different changing relationships between the horizontal displacement amount of the screw rod and the vertical displacement amount of the tray in the process of controlling the scissor mechanism to execute the first lifting operation when the tray is loaded with M loads with known and different weights, and M is a positive integer greater than or equal to 2.
In an alternative embodiment, the processing module 1004 includes: the obtaining unit is used for obtaining a plurality of line segments based on the N pairs of displacement amounts, wherein the line segments are obtained by sequentially connecting coordinate points represented by each pair of displacement amounts in the N pairs of displacement amounts; the first fitting unit is used for fitting the plurality of line segments to obtain the target curve; or a second fitting unit, configured to fit coordinate points represented by each pair of displacement amounts in the N pairs of displacement amounts, so as to obtain the target curve.
In an alternative embodiment, the apparatus further comprises: the execution module is used for executing the following operations for an ith load in the M loads before the first lifting operation is executed by the control automatic guided vehicle fork mechanism, so as to obtain an ith curve corresponding to the ith load, wherein i is a positive integer which is greater than or equal to 1 and less than or equal to M, and the M curves comprise the ith curve: controlling the scissor mechanism to execute the first lifting operation and acquire a P pair of displacement amounts in response to a received second target instruction when the tray is loaded with the ith load, wherein the P pair of displacement amounts are used for representing the horizontal displacement amounts of the screw rod and the vertical displacement amounts of the tray, which are acquired at P moments in the process of executing the first lifting operation and are in the case that the weight of the ith load generates the ith deformation on a joint node in the scissor mechanism, and P is a positive integer greater than or equal to 2; obtaining the ith curve based on the P pairs of displacement, wherein the ith curve corresponds to the weight of the ith load; and the obtaining module is used for obtaining the M curves according to the ith curve.
In an alternative embodiment, the first determining module 1006 includes: the searching unit is used for searching a curve matched with the target curve in the M curves; and the determining unit is used for determining the weight of the target load according to the weight corresponding to the curve matched with the target curve under the condition that the curve matched with the target curve is found.
In an alternative embodiment, the searching unit includes: an operation subunit, configured to perform the following operations on each curve of the M curves, where each curve is a current curve when the following operations are performed: determining a first set of points on the current curve and a second set of points on the target curve, wherein the first set of points and the second set of points each comprise Q points, and the abscissa of the Q points in the first set of points is the same as the abscissa of the Q points in the second set of points, wherein Q is a positive integer greater than or equal to 1; determining differences between the ordinate of the Q points in the first set of points and the ordinate of the Q points in the second set of points, resulting in Q differences altogether; determining an average value or an accumulated value of the Q differences as a distance between the current curve and the target curve; determining that the current curve is a curve matched with the target curve under the condition that the distance between the current curve and the target curve is smaller than or equal to a preset threshold value; and determining that the current curve is not a curve matched with the target curve under the condition that the distance between the current curve and the target curve is larger than the preset threshold value.
In an alternative embodiment, the determining unit includes: a determining subunit, configured to determine, when one curve matching the target curve is found, a weight corresponding to the curve matching the target curve as a weight of the target load; or the obtaining subunit is used for carrying out weighted summation on the weights corresponding to the two adjacent curves under the condition that the two adjacent curves matched with the target curve are found, so as to obtain the weight of the target load.
In an alternative embodiment, the apparatus further comprises: and the second determining module is used for determining the operation parameters of the automatic guided vehicle according to the weight of the target load after the weight of the target load is determined, wherein the operation parameters comprise the operation speed of the automatic guided vehicle.
It should be noted that each of the above modules may be implemented by software or hardware, and for the latter, it may be implemented by, but not limited to: the modules are all located in the same processor; alternatively, the above modules may be located in different processors in any combination.
Embodiments of the present invention also provide a computer readable storage medium having a computer program stored therein, wherein the computer program is arranged to perform the steps of any of the method embodiments described above when run.
In one exemplary embodiment, the computer readable storage medium may include, but is not limited to: a usb disk, a Read-Only Memory (ROM), a random access Memory (Random Access Memory, RAM), a removable hard disk, a magnetic disk, or an optical disk, or other various media capable of storing a computer program.
An embodiment of the invention also provides an electronic device comprising a memory having stored therein a computer program and a processor arranged to run the computer program to perform the steps of any of the method embodiments described above.
In an exemplary embodiment, the electronic apparatus may further include a transmission device connected to the processor, and an input/output device connected to the processor.
Specific examples in this embodiment may refer to the examples described in the foregoing embodiments and the exemplary implementation, and this embodiment is not described herein.
It will be appreciated by those skilled in the art that the modules or steps of the invention described above may be implemented in a general purpose computing device, they may be concentrated on a single computing device, or distributed across a network of computing devices, they may be implemented in program code executable by computing devices, so that they may be stored in a storage device for execution by computing devices, and in some cases, the steps shown or described may be performed in a different order than that shown or described herein, or they may be separately fabricated into individual integrated circuit modules, or multiple modules or steps of them may be fabricated into a single integrated circuit module. Thus, the present invention is not limited to any specific combination of hardware and software.
The above description is only of the preferred embodiments of the present invention and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A method of determining the weight of a load, comprising:
under the condition that a tray of the automatic guided vehicle is loaded with a target load, responding to a received first target instruction, controlling a fork shearing mechanism of the automatic guided vehicle to execute a first lifting operation, wherein the tray is arranged above the fork shearing mechanism, and the first lifting operation is used for controlling a screw rod in the automatic guided vehicle to move a first distance along a horizontal direction and driving the fork shearing mechanism to move a second distance along a vertical direction by the screw rod;
acquiring N pairs of displacement amounts in the process of executing the first lifting operation, and determining a target curve based on the N pairs of displacement amounts, wherein the N pairs of displacement amounts are used for representing the horizontal displacement amounts of the screw rods and the vertical displacement amounts of the trays acquired at N moments in the process of executing the first lifting operation, N is a positive integer greater than or equal to 2, and the target curve represents a change relationship between the horizontal displacement amounts of the screw rods and the vertical displacement amounts of the trays in the process of controlling the scissor mechanism to execute the first lifting operation under the condition that the trays are loaded with the target load;
And determining the weight of the target load according to the target curve and a preset M curve, wherein the M curves are used for representing different change relations between the horizontal displacement amount of the screw rod and the vertical displacement amount of the tray in the process of controlling the scissor mechanism to execute the first lifting operation under the condition that the tray is respectively loaded with M loads with known weights and different weights, and the different change relations are related to different deformations generated by the weights of the M loads on joint nodes in the scissor mechanism, and M is a positive integer greater than or equal to 2.
2. The method of claim 1, wherein the determining a target curve based on the N pairs of displacement amounts comprises:
obtaining a plurality of line segments based on the N pairs of displacement amounts, wherein the line segments are obtained by sequentially connecting coordinate points represented by each pair of displacement amounts in the N pairs of displacement amounts; fitting the line segments to obtain the target curve; or alternatively
Fitting coordinate points represented by each pair of displacement in the N pairs of displacement to obtain the target curve.
3. The method of claim 1, wherein prior to the controlling the scissor mechanism of the automated guided vehicle to perform the first lifting operation, the method further comprises:
For an ith load in the M loads, executing the following operations to obtain an ith curve corresponding to the ith load, wherein i is a positive integer greater than or equal to 1 and less than or equal to M, and the M curves comprise the ith curve: controlling the scissor mechanism to execute the first lifting operation and acquire a P pair of displacement amounts in response to a received second target instruction when the tray is loaded with the ith load, wherein the P pair of displacement amounts are used for representing the horizontal displacement amounts of the screw rod and the vertical displacement amounts of the tray, which are acquired at P moments in the process of executing the first lifting operation and are in the case that the weight of the ith load generates the ith deformation on a joint node in the scissor mechanism, and P is a positive integer greater than or equal to 2; obtaining the ith curve based on the P pairs of displacement, wherein the ith curve corresponds to the weight of the ith load;
and obtaining the M curves according to the ith curve.
4. The method of claim 1, wherein determining the weight of the target load from the target curve and a predetermined M curves comprises:
Searching curves matched with the target curve in the M curves;
and under the condition that the curve matched with the target curve is found, determining the weight of the target load according to the weight corresponding to the curve matched with the target curve.
5. The method of claim 4, wherein the finding a curve in the M curves that matches the target curve comprises:
the following operations are executed on each curve in the M curves respectively, wherein the each curve is a current curve when the following operations are executed:
determining a first set of points on the current curve and a second set of points on the target curve, wherein the first set of points and the second set of points each comprise Q points, and the abscissa of the Q points in the first set of points is the same as the abscissa of the Q points in the second set of points, wherein Q is a positive integer greater than or equal to 1;
determining differences between the ordinate of the Q points in the first set of points and the ordinate of the Q points in the second set of points, resulting in Q differences altogether;
determining an average value or an accumulated value of the Q differences as a distance between the current curve and the target curve;
Determining that the current curve is a curve matched with the target curve under the condition that the distance between the current curve and the target curve is smaller than or equal to a preset threshold value;
and determining that the current curve is not a curve matched with the target curve under the condition that the distance between the current curve and the target curve is larger than the preset threshold value.
6. The method of claim 4, wherein determining the weight of the target load from the weight corresponding to the curve matching the target curve comprises:
determining the weight corresponding to the curve matched with the target curve as the weight of the target load under the condition that one curve matched with the target curve is found; or alternatively
And under the condition that two adjacent curves matched with the target curve are found, carrying out weighted summation on weights corresponding to the two adjacent curves to obtain the weight of the target load.
7. The method according to any one of claims 1 to 6, wherein after said determining the weight of the target load, the method further comprises:
and determining an operating parameter of the automatic guided vehicle according to the weight of the target load, wherein the operating parameter comprises the operating speed of the automatic guided vehicle.
8. A load weight determining apparatus, comprising:
the control module is used for responding to the received first target instruction under the condition that a tray of the automatic guiding vehicle is loaded with the target load, and controlling a fork shearing mechanism of the automatic guiding vehicle to execute a first lifting operation, wherein the tray is arranged above the fork shearing mechanism, and the first lifting operation is used for controlling a screw rod in the automatic guiding vehicle to move a first distance along the horizontal direction and driving the fork shearing mechanism to move a second distance along the vertical direction by the screw rod;
a processing module configured to acquire N pairs of displacement amounts during execution of the first lifting operation, and determine a target curve based on the N pairs of displacement amounts, where the N pairs of displacement amounts are used to represent a horizontal displacement amount of the screw and a vertical displacement amount of the tray acquired at N times during execution of the first lifting operation, and N is a positive integer greater than or equal to 2, and the target curve represents a change relationship between the horizontal displacement amount of the screw and the vertical displacement amount of the tray during control of the scissor mechanism during execution of the first lifting operation in a case where the tray is loaded with the target load;
The first determining module is configured to determine the weight of the target load according to the target curve and a preset M curves, where the M curves are used to represent different change relationships between the horizontal displacement amount of the screw rod and the vertical displacement amount of the tray in the process of controlling the scissor mechanism to execute the first lifting operation when the tray is loaded with M loads with known and different weights, and M is a positive integer greater than or equal to 2.
9. A computer readable storage medium, characterized in that a computer program is stored in the computer readable storage medium, wherein the computer program, when being executed by a processor, implements the steps of the method according to any of the claims 1 to 7.
10. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, characterized in that the processor implements the steps of the method of any one of claims 1 to 7 when the computer program is executed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310800214.6A CN116818072A (en) | 2023-06-30 | 2023-06-30 | Method and device for determining load weight, storage medium and electronic device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310800214.6A CN116818072A (en) | 2023-06-30 | 2023-06-30 | Method and device for determining load weight, storage medium and electronic device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116818072A true CN116818072A (en) | 2023-09-29 |
Family
ID=88127264
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310800214.6A Pending CN116818072A (en) | 2023-06-30 | 2023-06-30 | Method and device for determining load weight, storage medium and electronic device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116818072A (en) |
-
2023
- 2023-06-30 CN CN202310800214.6A patent/CN116818072A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP3106423A1 (en) | Systems and methods for weight determination and closed loop speed control | |
| US9870002B1 (en) | Velocity control of position-controlled motor controllers | |
| CN109987550B (en) | Calibration method and storage medium for high-position forklift and returning storage container | |
| CN108146960A (en) | A kind of article automatic access device | |
| JPH0747403B2 (en) | Program-controlled box / container operation / transfer device | |
| WO2023020157A1 (en) | Automated guided vehicle and automated guided vehicle system | |
| JP2021062964A (en) | Goods transport system using autonomous traveling forklift and automated guided vehicle | |
| CN109335531B (en) | Material taking and discharging method for shuttle vehicle | |
| CN116495677B (en) | Transfer robot with guiding mechanism | |
| CN112573241A (en) | Automatic loading and unloading system and unloading method for reel materials | |
| CN116818072A (en) | Method and device for determining load weight, storage medium and electronic device | |
| CN112793982B (en) | Stacker goods taking and placing system and application method thereof | |
| Cui et al. | Design of a novel AGV with automatic pick-and-place system based on scissor lifting platform | |
| CN115571537B (en) | Long rod piece electric power material self-loading and unloading robot and self-loading and unloading system | |
| Özbaran et al. | Mechatronic System Design of A Smart Mobile Warehouse Robot for Automated Storage/Retrieval Systems | |
| US11983013B2 (en) | Traveling parameter optimization system and traveling parameter optimization method | |
| US20220073325A1 (en) | Automatic traveling system and traveling instruction method | |
| Soyaslan et al. | An approach of control system for automated storage and retrieval system (AS/RS) | |
| CN113173505A (en) | Automatic bottom-opening stacking method and system for gantry crane storage yard, storage medium and gantry crane | |
| CN110668056A (en) | Intelligent warehousing system | |
| CN218287934U (en) | Carrier and carrier system | |
| JP3997597B2 (en) | Delivery shelf selection method and delivery shelf selection device in automatic warehouse | |
| CN112550521B (en) | Intelligent loading and unloading robot, system and control method for intelligent factory | |
| CN114455508B (en) | AGV lifting high-precision stopping device and control method thereof | |
| Shen et al. | Movement and binding control strategy based on a new type of rebar-binding robot |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |