CNC feeding and discharging composite robot system and precision compensation method thereof

Abstract

The invention relates to the technical field of robots, in particular to a CNC feeding and discharging composite robot system and a precision compensation method thereof.Through cooperative use of an AGV chassis, a loading platform, a mechanical arm and a clamp, one robot system can drive multiple machine tools to conduct feeding and discharging operation, and by measuring the rigidity of the AGV chassis and the loading platform, the precision compensation precision of the CNC feeding and discharging composite robot system is improved. And calculating the acting force and the moment of force on the AGV chassis when the robot is at the discharging point, thereby calculating the deformation quantity of the AGV chassis, calculating the point position deviation influence of the deformation quantity of the AGV chassis on the tail end of the robot, and compensating the error into a robot control system through the robot kinematics, thereby realizing the error compensation of the composite robot. The material taking and placing precision of the composite robot is improved, and the technical problem that when an existing composite robot carries out feeding and discharging operation, due to the fact that an AGV is adopted for a chassis, the rigidity of the AGV is weak, deformation is likely to happen when the mechanical arm moves, and consequently position deviation is likely to happen when the mechanical arm takes and places materials is solved.

Description

Technical Field

[0001] The present invention relates to the field of robot technology, and in particular to a CNC loading and unloading composite robot system and a precision compensation method thereof. Background Art

[0002] Traditional machine factories use manual labor or fixed robotic arms to load and unload materials. When manual labor is used, the workers' workload is high, while when fixed robotic arms are used, one robotic arm generally covers 1-3 machine tools, and the utilization rate is not high enough. At the same time, the robot cannot move, the production flexibility is insufficient, and it occupies a large area.

[0003] The use of composite robots for loading and unloading can cover more machine tools (4 to 20 machines can be covered depending on the processing time of the machine tools). At the same time, the layout is more flexible and the production change is faster, which greatly improves production efficiency. However, compared with fixed robots, the mechanical and electrical systems of composite robots are more complex, and the functions they implement are also more complex, so reasonable structural, electrical, and system designs are required.

[0004] At the same time, since the chassis of the composite robots all use AGV, their rigidity is relatively weak and they are prone to deformation when the robotic arm moves, which causes position deviation when the robotic arm picks up and places materials. Therefore, it is necessary to perform flexible compensation on the composite robots to improve the robot's picking and placing accuracy, improve its scope of application and the stability of picking and placing materials. Summary of the invention

[0005] The purpose of the present invention is to provide a CNC loading and unloading compound robot system and its accuracy compensation method, which solves the technical problem that when the existing compound robots are performing loading and unloading operations, since the chassis adopts AGV, its rigidity is weak and it is easy to deform when the robot arm moves, which easily leads to position deviation of the robot arm when taking and placing materials.

[0006] To achieve the above-mentioned object, the present invention provides a CNC loading and unloading composite robot system, comprising a CNC machine tool, a visual calibration plate and a composite robot, wherein the CNC machine tool and the composite robot are both placed on the ground, and the visual calibration plate is arranged outside the CNC machine tool;

[0007] The composite robot includes an AGV chassis, an upper loading platform, a robotic arm and a clamp. The AGV chassis is used to move each of the CNC machine tools. The upper loading platform is arranged on the AGV chassis to provide a storage space for various devices and workpieces. The robotic arm is arranged on the upper loading platform to take and place materials. The clamp is arranged on the side of the robotic arm away from the upper loading platform to perform camera positioning of the robot and suction or placement of materials.

[0008] Among them, the wheels at the bottom of the AGV chassis adopt double Ackerman wheels, and the double Ackerman wheels are used to realize X and Y direction movement in situ, so as to reduce the movement and turning time in the parallel machine tools and improve the operation efficiency.

[0009] Among them, the upper loading platform includes a robot and a visual controller, an inverter, a mobile air source, a triplet, a secondary positioning device, a raw material tray, a cooked material tray and a pressure indicator. Through the coordinated use of the robot and the visual controller, the inverter, the mobile air source, the triplet, the secondary positioning device, the raw material tray, the cooked material tray and the pressure indicator, a storage space is provided for various devices and workpieces.

[0010] Among them, the clamp includes a material picking and placing module and a visual module. The material picking and placing module is used to grab raw materials, grab cooked materials, grab cover plates and grab air blowing heads, and the visual module is used to perform visual photography positioning.

[0011] The material picking and placing module comprises a suction cup, raw material, a cover plate, a blowing head fixture and clinker. The raw material, the clinker, the cover plate and the blowing head are grasped by the coordinated use of the suction cup and the blowing head fixture.

[0012] Wherein, the visual module includes a visual lens and a visual protection plate, and visual camera positioning is achieved through the coordinated use of the visual lens and the visual protection plate.

[0013] The present invention also provides a method for compensating the accuracy of a CNC loading and unloading composite robot system, comprising the following steps:

[0014] Measuring the stiffness of the AGV chassis, measuring the stiffness of the AGV chassis and the upper loading platform when subjected to X-direction positive force, X-direction moment, and Y-direction moment;

[0015] Calculate the force exerted by the AGV chassis on the vehicle body, and use the robot dynamics algorithm to solve the torque exerted by the AGV chassis on the vehicle body in the X and Y directions when the robot is at the material discharge point;

[0016] Calculate the deformation of the AGV chassis and the upper loading platform, first calculate the Z-direction deformation of the AGV chassis and the upper loading platform, and then calculate the deformation angles of the AGV chassis and the upper loading platform in the X and Y directions;

[0017] Calculate the deformation of the robot end, obtain the position of the fixture relative to the robot base when the robot is at the material picking and placing point through the robot kinematic model, and calculate the change amount of the robot end fixture in the X and Y directions;

[0018] Precision compensation: after obtaining the deviation of the robot end, the deviation is compensated to the controller for reverse compensation.

[0019] The present invention discloses a CNC loading and unloading composite robot system and its precision compensation method. Through the coordinated use of the AGV chassis, the upper loading platform, the mechanical arm and the clamp, one robot system can drive multiple machine tools to perform loading and unloading operations. By measuring the stiffness of the AGV chassis and the upper loading platform, and calculating the force and torque of the robot on the AGV chassis at the material discharge point, the deformation of the AGV chassis is calculated, and the influence of the deformation of the AGV chassis on the point deviation of the robot terminal is calculated. Then, through the robot kinematics, the error is compensated to the robot control system, thereby realizing error compensation of the composite robot and improving the material picking and unloading accuracy of the composite robot. The technical problem that the existing composite robots use AGV for the chassis, which has weak stiffness and is easily deformed when the mechanical arm moves, thus easily causing position deviation of the mechanical arm when picking and unloading is solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below.

[0021] Figure 1 It is a schematic diagram of the overall structure of the CNC loading and unloading compound robot system of the first embodiment of the present invention.

[0022] Figure 2 It is a schematic structural diagram of a composite robot according to the first embodiment of the present invention.

[0023] Figure 3 It is a schematic structural diagram of an AGV chassis according to the first embodiment of the present invention.

[0024] Figure 4 It is a schematic structural diagram of the upper loading platform of the first embodiment of the present invention.

[0025] Figure 5 1 is a schematic structural diagram of a clamp according to a first embodiment of the present invention.

[0026] Figure 6 It is a flow chart of the precision compensation method of the CNC loading and unloading compound robot system according to the second embodiment of the present invention.

[0027] In the figure: 101-CNC machine tool, 102-vision calibration plate, 103-composite robot, 104-AGV chassis, 105-upper loading platform, 106-mechanical arm, 107-clamp, 108-lifting mechanism, 109-wheel, 110-laser radar, 111-mounting plate, 112-robot and vision controller, 113-inverter, 114-mobile air source, 115-triplet, 116-secondary positioning device, 117-raw material tray, 118-cooked material tray, 119-pressure indicator, 120-suction cup, 121-raw material, 122-cover plate, 123-blowing head fixture, 124-cooked material, 125-floating device, 126-visual lens, 127-visual protection plate. DETAILED DESCRIPTION

[0028] Embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, but should not be construed as limiting the present invention.

[0029] First embodiment:

[0030] See also Figures 1 to 5 The present invention provides a CNC loading and unloading composite robot system, comprising a CNC machine tool, a visual calibration plate and a composite robot, the composite robot comprising an AGV chassis, an upper loading platform, a mechanical arm and a fixture, the upper loading platform comprising a robot and a visual controller, an inverter, a mobile air source, a triple piece, a secondary positioning device, a raw material tray, a cooked material tray and a pressure indicator, the fixture comprising a material picking and placing module and a visual module, the material picking and placing module comprising a suction cup, raw material, a cover plate, a blowing head fixture, cooked material and a floating device, the visual module comprising a visual lens and a visual protection plate.

[0031] In this embodiment, through the coordinated use of the AGV chassis, the upper loading platform, the robotic arm and the clamp, one robot system can drive multiple machine tools to perform loading and unloading operations.

[0032] Among them, the CNC machine tool and the composite robot are both placed on the ground, the visual calibration plate is arranged outside the CNC machine tool, the AGV chassis is used to move each of the CNC machine tools, the upper loading platform is arranged on the AGV chassis, and is used to provide a storage space for various devices and workpieces, the robotic arm is arranged on the upper loading platform, and is used to take and place materials, and the fixture is arranged on the side of the robotic arm away from the upper loading platform, and is used for taking pictures and positioning the robot and sucking or placing materials.

[0033] Secondly, the wheels at the bottom of the AGV chassis adopt double Ackerman wheels, which are used to realize X and Y direction movement in situ, so as to reduce the movement and turning time in parallel machine tools and improve the operation efficiency. The surface of the double Ackerman wheels at the bottom of the AGV chassis adopts twill polyurethane to achieve the purpose of quietness and anti-slip. A jacking mechanism is arranged under the AGV chassis. After reaching the working point, the jacking mechanism lifts the body to prevent the tires from slipping when the robot moves and causing the position of the AGV chassis to shift. A laser radar is arranged outside the AGV chassis. The laser radar realizes automatic navigation through the built-in navigation algorithm, and realizes automatic obstacle avoidance and collision warning through the built-in anti-collision algorithm.

[0034] At the same time, through the coordinated use of the robot and the visual controller, the inverter, the mobile air source, the triple piece, the secondary positioning device, the raw material tray, the cooked material tray and the pressure indicator, a space for accommodating various devices and workpieces is provided. By setting the secondary positioning device, the workpiece to be clamped by the robot arm can be secondary positioned to ensure that the robot arm picks up the same point of the workpiece each time, thereby ensuring the accuracy of picking and placing materials. A three-dimensional protection module is arranged around the robot arm, and the three-dimensional protection module can form a laser protection net around the robot arm. When the robot arm is in a non-tooling state, the protection net is opened. When the robot moves abnormally and touches the protection net, the three-dimensional protection module will transmit a signal to the control system of the robot arm to achieve emergency braking and avoid personal and property losses caused by abnormal movement of the robot. When the robot arm moves, the protection net is closed to ensure that the robot arm can operate normally.

[0035] In addition, the material picking and placing module is used for grabbing raw materials, grabbing cooked materials, grabbing cover plates and grabbing blowing heads, and the visual module is used for visual photography and positioning.

[0036] Finally, by using the suction cup and the blowing head clamp in coordination, the raw material, the clinker, the cover plate and the blowing head can be grasped. The floating device is used to automatically correct the deviation when a small deviation occurs at the pick-up and placement points to ensure the placement accuracy. By using the visual lens and the visual protection plate in coordination, visual camera positioning can be achieved. The visual protection plate can effectively prevent the machine tool cutting fluid from splashing onto the lens, thereby ensuring the stability and life of the lens.

[0037] When using a CNC loading and unloading composite robot system of the present embodiment, the AGV chassis establishes a map in the working area through the laser radar to identify the position of each machine tool and the loading point. First, the AGV chassis is moved to the loading point, and the raw material is placed on the raw material tray on the upper body through the loading mechanism. Then, the AGV chassis moves to the first machine tool and stops, and the entire composite robot is lifted up by the lifting mechanism to lift the wheels of the AGV chassis off the ground and send a signal to the CNC machine tool. After the CNC machine tool receives the signal, it opens the automatic door on the machine tool. At this time, the robotic arm takes a picture of the visual calibration plate on the machine tool through the visual lens on the fixture at the end, and confirms the machine tool's material picking and unloading points by comparing the points on the visual calibration plate with the taught theoretical points.

[0038] After the photo positioning is completed, the robotic arm is moved to the raw material tray to grab the raw material, and put it into the secondary positioning device for secondary positioning, and the raw material is grabbed from the secondary positioning device, and then the robotic arm is extended into the machine tool, and the processed clinker is sucked onto the clamp through the clamp, and the clamp is rotated to put the raw material into the machine tool, and then the robotic arm exits the machine tool, and a material taking and placing completion signal is sent to the machine tool, and the clinker is put into the clinker tray of the upper loading. After the machine tool receives the signal, the automatic door is closed, and processing is started, and a door closing signal is sent to the composite robot. After the composite robot receives the signal, it starts to move to the next machine tool and repeats the above process. When the raw material on the upper loading is used up, the composite robot returns to the loading position, puts the clinker into the material frame, loads the raw material, and then continues to work.

[0039] The motion positioning of the composite robot involves the determination of the relationship between five coordinate systems, namely, the machine tool material picking and placing coordinate system W, the visual calibration plate coordinate system B, the AGV coordinate system V, the robot coordinate system R, and the fixture coordinate system T.

[0040] Among them, the relative position of coordinate system W and B is a fixed value, and the relative position of coordinate system V and R is theoretically a fixed value. After the position relationship of coordinate system R and T is calibrated, the parameters are written into the robot controller and obtained through kinematic solution. The relationship between coordinate system B and T is obtained through visual calibration. When teaching for the first time, the system will record the relationship between coordinate system R and coordinate system B and the relationship between coordinate system R and coordinate system W.

[0041] When the AGV chassis drives near the machine tool again, the compound robot takes a photo through the visual lens to confirm the relationship between the coordinate system R and the coordinate system B, and compares it with the relationship between the coordinate systems R and B during teaching, so as to analyze the deviation of the compound robot relative to the time of teaching, and compensate the amount to the relationship between R and W, so as to correct the position of the robotic arm when the compound robot grasps.

[0042] Second embodiment:

[0043] Based on the first embodiment, please refer to Figure 6 The present invention also provides a method for compensating the accuracy of a CNC loading and unloading composite robot system, comprising the following steps:

[0044] S101, measuring the stiffness of the AGV chassis, measuring the stiffness of the AGV chassis and the upper loading platform when subjected to X-direction positive force, X-direction moment, and Y-direction moment.

[0045] Specifically, it is necessary to accurately measure the deformation of the AGV and the upper body, and confirm the transformation relationship between the coordinate system V and the coordinate system R after deformation. Let k Z Indicates the stiffness of the AGV and the upper body when subjected to X-direction positive force, k Mx Indicates the stiffness of the AGV and the upper body when subjected to the X-direction moment, k My Indicates the stiffness of the AGV and the upper body when subjected to moment in the Y direction. The unit of force stiffness is N / mm, and the unit of moment stiffness is Nm / rad.

[0046] The above stiffness is tested by the following method.

[0047] Measuring k z

[0048] Install a measuring rod with a measuring length of L on the upper loading platform, and install a laser tracker target ball at the end of the measuring rod. Use weights of different masses m1, m2, m3...m at the upper loading robot installation location. n Loading is performed to test the displacement of the target ball under different loads, Δp1, Δp2, and Δp3. The relationship between the loading weight and the displacement of the target ball is used to solve k using the least squares method. z

[0049] The weight exerted by the weight

[0050] F i =m i g

[0051] Find the stiffness k z , so that

[0052]

[0053] Measuring k Mx

[0054] Install a measuring rod with a measuring length of L on the upper loading platform, and install a laser tracker target ball at the end of the measuring rod. x The force rod has no weights of different masses m installed at the end of the force rod. 1x , m 2x , m 3x ……m nx Loading is performed to test the displacement Δp of the target ball under different loads. 1x , Δp 2x , Δp 3x ..., use the least squares method to solve k Mx

[0055] Torque applied by weight

[0056] M xi =m i g x

[0057] Find the stiffness k Mx , so that

[0058]

[0059] Measuring k My

[0060] Install a measuring rod with a measuring length of L on the upper loading platform, and install a laser tracker target ball at the end of the measuring rod. y The force rod has no weights of different masses m installed at the end of the force rod. 1y , m 2y , m 3y ……m ny Loading is performed to test the displacement Δp of the target ball under different loads. 1y , Δp 2y , Δp 3y ..., use the least squares method to solve k My

[0061] Torque applied by weight

[0062] M yi =m i g y

[0063] Find the stiffness k Mx , so that

[0064]

[0065] S102, calculating the force exerted by the AGV chassis on the vehicle body, and solving the torque exerted by the AGV chassis on the vehicle body in the X direction and the Y direction when the robot is at the material discharge point through the robot dynamics algorithm.

[0066] Specifically, the robot dynamics algorithm is used to solve the reaction force of the robot base on the car body when the robot is at the material discharge point. First, the speed and acceleration of the robot link are iteratively calculated from link 1 to link n outward. The method is as follows:

[0067] Extrapolation:

[0068]

[0069] Fill link n to link 1 and iterate inward to calculate the interaction force between the links

[0070] Internal recommendation:

[0071]

[0072] The above method is used to solve the force f and moment n exerted by the base on the vehicle body when the robot is at the unloading point.

[0073] Find the separation of the forces in the Z direction

[0074]

[0075] Calculate the torque of the robot base on the vehicle body in the X and Y directions

[0076]

[0077] S103, calculating the deformation of the AGV chassis and the upper loading platform, first calculating the Z-direction deformation of the AGV chassis and the upper loading platform, and then calculating the deformation angles of the AGV chassis and the upper loading platform in the X-direction and the Y-direction.

[0078] Specifically, calculate the Z-axis deformation of the AGV and the upper body

[0079] Δz v =f z / k z

[0080] Calculate the X-direction deformation angle of AGV and upper equipment

[0081] Δx vθ =n x / k Mx

[0082] Calculate the Y-direction deformation angle of AGV and upper equipment

[0083] Δy vθ =n y / kMy

[0084] S104, calculating the deformation of the robot end, obtaining the position of the fixture relative to the robot base when the robot is at the material picking and placing point through the robot kinematic model, and calculating the change amount of the robot end fixture in the X direction and the Y direction.

[0085] Specifically, through the robot kinematic model, we can know the position P of the fixture relative to the robot base when the robot is at the material picking and placing point. T

[0086]

[0087] Assume that the change in the position of the robot end fixture is

[0088]

[0089] The change in the Z direction of the robot end fixture is the same as the deformation of the AGV and the upper device in the Z direction, that is,

[0090] Δp Tz =Δz

[0091] Change in the X direction of the robot end fixture

[0092] Δp Tx =Δx vθ .p Tx

[0093] Change in the Y direction of the robot end fixture

[0094] Δp Ty =Δy vθ .p Ty

[0095] S105, precision compensation, after obtaining the deviation of the end of the robot, the deviation is compensated to the controller for reverse compensation.

[0096] Specifically, after obtaining the deviation of the robot end, it is compensated to the controller for reverse compensation. Assume that the required point position of the robot end is P Ti The robot kinematics calculates the theoretical point as P Tidl After calculating the robot end error as above, the command point actually given by the controller should be P Tidl +ΔP T , thereby realizing the flexible error compensation of the AGV chassis and the upper loading platform of the composite robot, and improving the material picking and placing accuracy of the composite robot.

[0097] When using the accuracy compensation method of a CNC loading and unloading compound robot system of the present embodiment, the robotic arm in the compound robot is installed on the upper loading platform, and the AGV chassis and the upper loading platform have a certain flexibility. When the robotic arm is extended into the machine tool to perform material picking and placing operations, the weight of the fixture, the weight of the workpiece and the deadweight of the robotic arm will cause a large load on the upper loading platform and the AGV chassis, causing them to deform and causing the relationship between the coordinate systems R and V to change. Therefore, it is necessary to perform flexibility compensation on this part to improve the accuracy of the compound robot.

[0098] Suppose the transformation matrix from coordinate system R to coordinate system T is The transformation relationship between coordinate system T and coordinate system B is The rest are similar. The conversion coordinate system not only represents the conversion relationship between coordinate systems, but also represents the position and posture of a certain coordinate in another coordinate. Its form is:

[0099]

[0100] in, To express attitude, Indicates a point.

[0101] During the first calibration, the AGV chassis stops in front of the machine tool, and the calibration algorithm can be used to obtain Through the robot kinematics calculation, we can get Can get That is, the spatial relationship between the AGV chassis and the calibration plate is obtained.

[0102] When the AGV chassis moves to the front of the machine tool for the second time, due to the motion error of the AGV chassis, its position has changed relative to the first point. Through visual recognition again, the relative relationship between the fixture and the calibration plate at this time is obtained. Same reason Through the robot kinematics calculation, we can get Compare and By obtaining the difference, the specific displacement deviation of the AGV chassis can be obtained, that is, Depend on Depend on After the point offset of the AGV chassis is calculated, the offset of the material picking and placing point relative to the robot is obtained, so that the robot can compensate for the changing offset and ensure the accuracy of material picking and placing.

[0103] In actual engineering, when the robot goes deep into the machine tool to pick up and place parts, it causes a large load on the AGV chassis and the upper loading platform, causing the AGV chassis and the upper loading platform to deform. has changed becomes a variable related to the movement of the robot arm and the grasping load.

[0104] At this time, it is necessary to measure the stiffness of the AGV chassis and the upper loading platform, and calculate the force and torque of the robot on the AGV chassis at the discharge point, so as to calculate the deformation of the AGV chassis and the influence of the deformation of the AGV chassis on the point deviation of the robot end. Through the robot kinematics, the error is compensated to the robot control system, so as to realize the error compensation of the composite robot and improve the accuracy of the composite robot in picking and discharging.

[0105] What is disclosed above is only one or more preferred embodiments of the present application, and cannot be used to limit the scope of rights of the present application. Ordinary technicians in this field can understand that all or part of the processes of implementing the above embodiments and equivalent changes made according to the claims of the present application are still within the scope covered by the present application.

Claims

1. A CNC loading and unloading composite robot system, characterized in that: It includes a CNC machine tool, a visual calibration plate and a composite robot, wherein the CNC machine tool and the composite robot are both placed on the ground, and the visual calibration plate is arranged outside the CNC machine tool; The composite robot includes an AGV chassis, an upper loading platform, a robotic arm and a clamp. The AGV chassis is used to move each of the CNC machine tools. The upper loading platform is arranged on the AGV chassis to provide a storage space for various devices and workpieces. The robotic arm is arranged on the upper loading platform to take and place materials. The clamp is arranged on the side of the robotic arm away from the upper loading platform to perform camera positioning of the robot and suction or placement of materials.

2. The CNC loading and unloading composite robot system according to claim 1, characterized in that: The wheels at the bottom of the AGV chassis are double Ackerman wheels, which are used to achieve X and Y direction movement in situ, so as to reduce the movement and turning time in parallel machine tools and improve the operation efficiency.

3. The CNC loading and unloading composite robot system according to claim 1, characterized in that: The upper loading platform includes a robot and a visual controller, an inverter, a mobile air source, a triplet, a secondary positioning device, a raw material tray, a cooked material tray and a pressure indicator. Through the coordinated use of the robot and the visual controller, the inverter, the mobile air source, the triplet, the secondary positioning device, the raw material tray, the cooked material tray and the pressure indicator, a storage space is provided for various devices and workpieces.

4. The CNC loading and unloading composite robot system according to claim 1, characterized in that: The fixture includes a material picking and placing module and a visual module. The material picking and placing module is used for grabbing raw materials, grabbing cooked materials, grabbing cover plates and grabbing blowing heads, and the visual module is used for visual photography and positioning.

5. The CNC loading and unloading composite robot system according to claim 4, characterized in that: The material picking and placing module comprises a suction cup, raw material, a cover plate, a blowing head fixture and clinker. The raw material, the clinker, the cover plate and the blowing head are grasped by the coordinated use of the suction cup and the blowing head fixture.

6. The CNC loading and unloading composite robot system according to claim 4, characterized in that: The visual module includes a visual lens and a visual protection plate, and visual camera positioning is achieved through the coordinated use of the visual lens and the visual protection plate.

7. A precision compensation method for a CNC loading and unloading compound robot system, applied to the CNC loading and unloading compound robot system according to any one of claims 1 to 6, characterized in that: The following steps are involved: Measuring the stiffness of the AGV chassis, measuring the stiffness of the AGV chassis and the upper loading platform when subjected to X-direction positive force, X-direction moment, and Y-direction moment; Calculate the force of the AGV chassis on the vehicle body, and use the robot dynamics algorithm to solve the torque of the AGV chassis on the vehicle body in the X and Y directions when the robot is at the material discharge point; Calculate the deformation of the AGV chassis and the upper loading platform, first calculate the Z-direction deformation of the AGV chassis and the upper loading platform, and then calculate the deformation angles of the AGV chassis and the upper loading platform in the X and Y directions; Calculate the deformation of the robot end, obtain the position of the fixture relative to the robot base when the robot is at the material picking and placing point through the robot kinematic model, and calculate the change amount of the robot end fixture in the X and Y directions; Precision compensation: after obtaining the deviation of the robot end, the deviation is compensated to the controller for reverse compensation.

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