Large component flexible positioning method based on three-dimensional force sensor

Abstract

This application discloses a flexible placement method for large components based on three-dimensional force sensors, relating to the field of large component assembly technology, aiming to solve the technical problems of stress tension and compression that occur during the assembly of large components in existing technologies. The flexible placement method for large components based on three-dimensional force sensors includes the following steps: installing three-dimensional force sensors on each locator, and calibrating the direction of each three-dimensional force sensor with the assembly coordinate system direction, so that the X, Y, and Z directions of each three-dimensional force sensor are parallel to each other; obtaining the theoretical placement position of the large component by measurement, controlling each locator to move the ball socket on each locator to the theoretical position; sequentially placing the ball heads of each large component into the corresponding ball sockets, and adjusting each locator based on the real-time feedback values ​​of each three-dimensional force sensor, so that the X-direction force value and Y-direction force value of each locator meet a preset threshold.

Description

Technical Field

[0001] This application relates to the field of large component assembly technology, and in particular to a flexible placement method for large components based on a three-dimensional force sensor. Background Technology

[0002] In industrial assembly, the placement of large components is an indispensable step. Currently, the placement of large components is achieved by using a laser tracker to measure the position of the component's ball joint in the assembly coordinate system as the theoretical position. A CNC positioner is then controlled to move the ball socket on the positioner to the theoretical position before hoisting and placement. This placement method does not take into account the measurement errors of the laser tracker and uneven contact between the ball joint of the large component and the ball socket of the positioner, which can cause stress tension and compression on the large component. Summary of the Invention

[0003] This application provides a flexible placement method for large components based on a three-dimensional force sensor, which at least solves the technical problem of stress tension and compression that occurs when assembling large components in the prior art.

[0004] To address the aforementioned technical problems, this application provides a method for the flexible placement of large components based on a three-dimensional force sensor, comprising the following steps:

[0005] The three-dimensional force sensors are installed on each positioner, and the orientation of each three-dimensional force sensor is calibrated with the orientation of the assembly coordinate system so that the X, Y, and Z directions of each three-dimensional force sensor are parallel to each other.

[0006] The theoretical placement position of the large component is obtained by measurement, and each of the positioning devices is controlled to move the ball socket on each positioning device to the theoretical position.

[0007] The ball heads of each major component are placed in their corresponding sockets in sequence. The positioners are adjusted based on the real-time feedback values ​​of each of the three-dimensional force sensors so that the X-direction force value and Y-direction force value of each positioner meet the preset threshold.

[0008] As some optional embodiments of this application, the locator includes a locator A in the lower left corner, a locator B in the upper left corner, a locator C in the upper right corner, and a locator D in the lower right corner.

[0009] The step of sequentially placing the ball heads of the major components into their corresponding sockets, and adjusting each positioner based on the real-time feedback values ​​of each of the three-dimensional force sensors so that the X-direction force values ​​and Y-direction force values ​​of each positioner meet preset thresholds, includes:

[0010] Large component A was lifted using a hoisting method. ’ Ball head and large component B ’The ball head is placed in the corresponding ball socket, and the B positioner is adjusted based on the real-time feedback value of the three-dimensional force sensor in the X direction of the B positioner;

[0011] The large component C was lifted using a hoisting method. ’ Ball head and large component D ’ The ball head is placed in the corresponding ball socket; the C positioner is adjusted based on the real-time feedback value of the three-dimensional force sensor in the Y direction based on the C positioner, the D positioner is adjusted based on the real-time feedback value of the three-dimensional force sensor in the Y direction based on the D positioner, and the D positioner is adjusted based on the real-time feedback value of the three-dimensional force sensor in the X direction based on the D positioner.

[0012] The positioners are fine-tuned based on a preset feedback control algorithm and real-time feedback values ​​so that the X-direction force value and Y-direction force value of each positioner meet the preset threshold.

[0013] As some optional embodiments of this application, the step of adjusting the B-positioner based on the real-time feedback value of the three-dimensional force sensor in the X direction of the B-positioner includes:

[0014] Based on the real-time X-axis feedback value of the three-dimensional force sensor of the B-positioner, the X-axis deformation of the A-positioner and the B-positioner is obtained. ;

[0015] Based on the X-direction deformation The positional relationship between locator A and locator B is used to obtain the target position of the ball socket of locator B.

[0016] Adjust the ball socket of the B locator to the target position of the ball socket of the B locator.

[0017] As some optional embodiments of this application, the X-direction deformation The following relationship must be satisfied:

[0018]

[0019] in, Let A and B be the X-direction deformations. This represents the distance between the centers of the ball sockets of locators A and B. Let E be the angular deviation between the ball-and-socket directions of positioners A and B and the X direction, and let E be the elastic modulus of the component material. The real-time feedback value of the three-dimensional force sensor in the X direction for the B-positioner. g 1 represents the threshold value of the absolute value of the X-axis force for both positioner A and positioner B.

[0020] As some optional embodiments of this application, the target position of the ball socket of the B locator satisfies the following relationship:

[0021]

[0022]

[0023] in, This represents the distance between the centers of the ball sockets of locators A and B. Let A and B be the X-direction deformations of the locator. , , ) represents the theoretical spatial coordinates of the center of the ball socket of locator A. , , ) represents the theoretical spatial coordinates of the ball-and-socket center of locator B. , , Let be the target position coordinates in space of the ball-and-socket center of locator B; where, .

[0024] As some optional embodiments of this application, the step of adjusting the C-positioner based on the real-time feedback value of the three-dimensional force sensor in the Y direction of the C-positioner includes:

[0025] Based on the real-time Y-axis feedback value of the three-dimensional force sensor of the C-positioner, the Y-axis deformation of the B-positioners and C-positioners is obtained. ;

[0026] Based on the Y-direction deformation The positional relationship between locator B and locator C is used to obtain the target position of the ball socket of locator C.

[0027] Adjust the C-positioner ball socket to the target position of the C-positioner ball socket.

[0028] As some optional embodiments of this application, the Y-direction deformation The following relationship must be satisfied:

[0029]

[0030] in, For the Y-direction deformation of locators B and C, This represents the distance between the centers of the ball and socket of locator B and locator C. Let E be the angular deviation between the ball-and-socket direction and the Y direction of positioners B and C, and let E be the elastic modulus of the component material. The value of the three-dimensional force sensor on the C-positioner about the Y direction. g 2 represents the absolute value threshold of the Y-axis force for both positioner B and positioner C.

[0031] As some optional embodiments of this application, the target position of the C-positioner ball socket satisfies the following relationship:

[0032]

[0033]

[0034] in, This represents the distance between the centers of the ball and socket of locator B and locator C. For the Y-direction deformation of locator B and locator C, ( , , ) represents the target position coordinates in space of the ball socket center of locator B. , , ) represents the target position coordinates in space of the center of the ball socket of the C-positioner; where, .

[0035] As some optional embodiments of this application, the step of adjusting the D-positioner based on the real-time feedback value of the three-dimensional force sensor in the Y direction of the D-positioner includes:

[0036] Based on the real-time Y-axis feedback value of the three-dimensional force sensor using the D-positioner, the Y-axis deformation of the A-positioner and the D-positioner is obtained. ;

[0037] Based on the Y-direction deformation The positional relationship between locator A and locator D is used to obtain the first target position of the ball socket of locator D.

[0038] Adjust the D-positioner ball socket to the first target position of the D-positioner ball socket.

[0039] As some optional embodiments of this application, the Y-direction deformation The following relationship must be satisfied:

[0040]

[0041] in, For the Y-direction deformation of locator A and locator D, The distance between the centers of the ball and socket of locator A and locator D. Let E be the angular deviation between the ball-and-socket direction and the Y direction of positioners A and D, and let E be the elastic modulus of the component material. The real-time feedback value of the three-dimensional force sensor in the Y direction for the D positioner. g 4 represents the absolute value threshold of the Y-axis force for both positioner A and positioner D.

[0042] As some optional embodiments of this application, the target position of the D-positioner ball socket satisfies the following relationship:

[0043]

[0044]

[0045] in, The distance between the centers of the ball and socket of locator A and locator D. For the Y-direction deformation of positioners A and D, ( , , ) represents the theoretical spatial coordinates of the center of the ball socket of locator A. , , ) represents the theoretical coordinates of the center of the D-positioner's ball socket in space. , , ) represents the calculated target position coordinates of the ball-and-socket center of the D-positioner in space; where, .

[0046] As some optional embodiments of this application, the fine-tuning of each positioner based on a preset feedback control algorithm and real-time feedback values, so that the X-direction force value and Y-direction force value of each positioner meet preset thresholds, includes:

[0047] After adjusting the ball socket of the D locator to the first target position of the ball socket of the D locator, the X-direction deformation of the C locator and the D locator is obtained based on the real-time X-direction feedback value of the three-dimensional force sensor of the D locator. ;

[0048] Based on the X-direction deformation The positional relationship between locator C and locator D is used to obtain the second target position of the ball socket of locator D;

[0049] Adjust the D-positioner ball socket to the second target position of the D-positioner ball socket.

[0050] As some optional embodiments of this application, the X-direction deformation The following relationship must be satisfied:

[0051]

[0052] in, For the X-direction deformation of the C-positioner and the D-positioner. The distance between the centers of the ball and socket of locator C and locator D. β Let E be the angular deviation between the ball-and-socket direction and the Y direction of the C and D positioners, and let E be the elastic modulus of the component material. The real-time X-axis feedback value of the three-dimensional force sensor of the D-positioner. g3 represents the threshold value of the absolute value of the X-direction force for both the C-positioner and the D-positioner.

[0053] As some optional embodiments of this application, the target position of the D-positioner ball socket satisfies the following relationship:

[0054]

[0055]

[0056] in, For the X-direction deformation of the C-positioner and the D-positioner. The distance between the centers of the ball and socket of locator C and locator D is ( , , ) represents the theoretical coordinates of the center of the D-positioner's ball socket in space. , , ) represents the target position coordinates in space of the center of the D-positioner's ball socket; where, .

[0057] As some optional embodiments of this application, the preset feedback control algorithm satisfies the following relationship:

[0058]

[0059] in, This represents the force value in the x-direction of the three-dimensional force sensor at time k. Let F be the force value in the y-direction of the three-dimensional force sensor at time k. x(k-1) The force value in the x-direction at time (k-1) of the three-dimensional force sensor. Let F be the force value in the y-direction of the three-dimensional force sensor at time k. y(k-1) This represents the force value in the y-direction at time (k-1) of the three-dimensional force sensor. g Let be the threshold values ​​in the X and Y directions of the three-dimensional force sensor, T be the sampling time, Ti be the integration time, Td be the differential time, and j be a certain moment in the integration time.

[0060] As some optional embodiments of this application, the step of obtaining the theoretical placement position of the large component by measurement and controlling each of the locators to move the ball and socket on each of the locators to the theoretical position includes:

[0061] A laser tracker was used for spatial modeling, and the theoretical position of the large component when it was in place was measured; among which, Here are the theoretical positioning coordinates of the ball-and-socket joint of locator A. The coordinates of the ball-and-socket theoretical positioning position of the B locator. The coordinates of the C-positioner's ball-and-socket theoretical positioning position are given. The coordinates of the D-positioner's ball-and-socket theoretical insertion position;

[0062] Based on the theoretical positioning coordinates of the ball sockets of each locator, each locator is controlled to move the ball sockets on each locator to the theoretical position.

[0063] Compared to existing technologies, the method provided in this application first requires installing three-dimensional force sensors on four positioners and calibrating the orientation of the force sensors with the assembly coordinate system, ensuring that the X, Y, and Z directions of the four force sensors are parallel to each other. Secondly, a laser tracker is used to measure the position of the ball joint of the large component in the assembly coordinate system as the theoretical position for insertion. The CNC positioners are then controlled to move the ball sockets on positioners A and B to the theoretical position. Finally, the large component is hoisted into place. , Two ball heads are placed in the ball sockets. The position of the B-positioner's X-axis is adjusted based on the real-time X-axis feedback value from the B-positioner's three-dimensional force sensor, causing the absolute value of the X-axis force to decrease to a threshold value. g 1. After adjustment, control the CNC positioner to move the ball joints on the C and D positioners to their theoretical positions. , The two ball joints were hoisted into position. After the entire assembly was in place, the Y-axis positions of the C and D positioners were adjusted based on the Y-feedback values ​​from the three-dimensional force sensors of the C and D positioners, so that the absolute value of the Y-axis force of the four positioners decreased to the threshold. g 2. g 4. Adjust the D positioner based on the real-time feedback value in the X direction from the three-dimensional force sensor so that the absolute values ​​of the force values ​​in the X direction of the C and D positioners decrease to the threshold. g 3. Finally, fine-tuning is performed using a real-time force feedback control algorithm to reduce the force on all axes (X and Y) to the threshold ζ. This utilizes a three-dimensional force sensor to achieve flexible positioning of large components, allowing real-time acquisition of the component's stress during positioning and controlling the positioner's movement based on this stress, thus avoiding or reducing stress tension and compression issues after positioning. Attached Figure Description

[0064] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0065] Figure 1 This is a schematic diagram showing the positional relationship of the ball joints of the large components involved in the embodiments of this application;

[0066] Figure 2 This is a schematic diagram of the locator structure involved in the embodiments of this application;

[0067] Figure 3 This is a schematic diagram showing the positional relationship between locator A and locator B involved in the embodiments of this application.

[0068] Figure 4 This is a schematic diagram showing the placement of the large components involved in the embodiments of this application after completion;

[0069] Figure 5 This is a schematic diagram showing the angle and positional relationship between the four CNC positioners after the insertion is completed, as described in the embodiments of this application.

[0070] In the diagram, 1 represents the main component, 2 represents the ball joint, 3 represents the motor, 4 represents the ball socket, 5 represents the Z-axis, 6 represents the X-axis, 7 represents the Y-axis, and 8 represents the positioner.

[0071] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0072] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0073] Example 1

[0074] Taking the placement of four positioners as an example, this is an example of a flexible placement method for large components based on a three-dimensional force sensor, which includes the following steps:

[0075] Step 1: Install three-dimensional force sensors on the four positioners and calibrate the orientation of the force sensors with the orientation of the assembly coordinate system so that the X, Y, and Z directions of the four force sensors are parallel to each other.

[0076] Calibration ensures that the three-dimensional force sensors of the four positioners are aligned. Since the large component is made of rigid material and the positioners move asynchronously, a monitoring threshold ε needs to be set for the force values ​​of all positioners in the X and Y directions. When the force value in either the X or Y direction exceeds this threshold, the positioner's movement will stop, thus protecting the large component.

[0077] Step 2: Obtain the theoretical position of the large component by measurement, and control the CNC positioner to move the ball sockets on positioners A and B to the theoretical position;

[0078] A laser tracker was used for spatial modeling, and the theoretical position of the large component during its placement was measured. , These represent the theoretical ball socket positions for locators A and B, respectively. Based on these theoretical positions, the axes of each locator are moved to ensure the ball sockets are in the correct positions.

[0079] Step 3: Hoist the large components , The two ball heads are placed in the ball socket;

[0080] large components , The two ball joints are hoisted into the ball sockets of locators A and B. The positional relationship of the ball joints of the large components is as follows: Figure 1 As shown, the locator looks like Figure 2 As shown in the figure; 1 represents the large component, 2 represents the ball head, 3 represents the motor, 4 represents the ball socket, 5 represents the Z-axis, 6 represents the X-axis, 7 represents the Y-axis, and 8 represents the positioner.

[0081] Step 4: Adjust the B positioner based on the real-time feedback value of the three-dimensional force sensor in the X direction; reduce the absolute value of the X-direction force of both the A and B positioners to the threshold. g 1;

[0082] Due to errors in measurement and hoisting, the three-dimensional force sensors on locators A and B will generate stress in the X direction. By using the real-time feedback value in the X direction from the three-dimensional force sensor on locator B, the deformation of the large component between the two locators can be calculated. : ;

[0083] in, Let A and B be the X-direction deformations. This represents the distance between the centers of the ball sockets of locators A and B. Let E be the angular deviation between the ball-and-socket directions of positioners A and B and the X direction, and let E be the elastic modulus of the component material. The real-time feedback value of the three-dimensional force sensor in the X direction for the B-positioner. g 1 represents the absolute value threshold of the X-axis force values ​​for locators A and B. The positional relationship between locators A and B is as follows: Figure 3 As shown.

[0084] By obtaining the deformation of the large component and the positional relationship between locator A and locator B, the target value of the ball socket center of locator B can be calculated, as shown in Formula 4-1 and Formula 4-2.

[0085] (4-1)

[0086] (4-2)

[0087] in, This represents the distance between the centers of the ball sockets of locators A and B. Let A and B be the X-direction deformations of the locator. , , ) represents the theoretical spatial coordinates of the center of the ball socket of locator A. , , ) represents the theoretical spatial coordinates of the ball-and-socket center of locator B. , , ) represents the target position coordinates in space of the ball socket center of the B locator.

[0088] Because the positioner's height remains consistent before and after force control adjustment, as shown in Formula 4-3.

[0089] (4-3)

[0090] The target position of the ball socket center of the B locator can be obtained by using formulas 4-1, 4-2, and 4-3.

[0091] Step 5: Control the CNC positioners to move the ball joints on positioners C and D to their corresponding theoretical positions, and then lift the large component using hoisting. , The two ball heads are placed in the ball socket; among them , These are the theoretical insertion positions of the ball sockets for positioners C and D, respectively. Based on these theoretical positions, the axes of each positioner are controlled to move until the ball sockets are in the correct insertion position. The large component is then lowered into the ball sockets of positioners C and D via hoisting. After the large component is in place, as shown... Figure 4 As shown.

[0092] Step 6: Adjust positioners C and D based on the real-time feedback values ​​of the three-dimensional force sensors in the Y direction, so that the absolute values ​​of the Y-direction force values ​​of positioners B and C decrease to the threshold. g 2. The absolute values ​​of the Y-axis forces of the A and D positioners decrease to the threshold. g 4;

[0093] By measuring the force values ​​in the Y direction from the three-dimensional force sensors of positioners C and D, the deformation in the Y direction between positioners A and D is calculated. : ;

[0094] in, For the Y-direction deformation of locator A and locator D, The distance between the centers of the ball and socket of locator A and locator D. Let E be the angular deviation between the ball-and-socket direction and the Y direction of positioners A and D, and let E be the elastic modulus of the component material. The real-time feedback value of the three-dimensional force sensor in the Y direction for the D positioner. g 4 represents the absolute value threshold of the Y-axis force for both positioner A and positioner D.

[0095] and the deformation between the two locators B and C : ;

[0096] in, For the Y-direction deformation of locators B and C, This represents the distance between the centers of the ball and socket of locator B and locator C. Let E be the angular deviation between the ball-and-socket direction and the Y direction of positioners B and C, and let E be the elastic modulus of the component material. The value of the three-dimensional force sensor on the C-positioner about the Y direction. g 2 represents the absolute value threshold of the Y-axis force for both positioner B and positioner C.

[0097] After the insertion is completed, the angular and positional relationships between the four CNC positioners are as follows: Figure 5 As shown.

[0098] By obtaining the deformation of the large component and the positional relationship between the A locator and the D locator, the target position that the ball socket of the D locator needs to move can be calculated, as shown in formulas 6-1 and 6-2.

[0099] (6-1)

[0100] (6-2)

[0101] in, The distance between the centers of the ball and socket of locator A and locator D. For the Y-direction deformation of positioners A and D, ( , , ) represents the theoretical spatial coordinates of the center of the ball socket of locator A. , , ) represents the theoretical coordinates of the center of the D-positioner's ball socket in space. , , () represents the target position coordinates in space of the center of the D-positioner ball socket after calculation.

[0102] Because the positioner height remains consistent before and after force control adjustment, as shown in Formula 6-3.

[0103] (6-3)

[0104] Similarly, the target position of the ball joint center of positioner C can be calculated by considering the deformation of the large components in the Y direction between positioners B and C, and the consistency of the positioner height before and after force control adjustment. This is shown in formulas 6-4, 6-5, and 6-6.

[0105] (6-4)

[0106] (6-5)

[0107] (6-6)

[0108] in, This represents the distance between the centers of the ball and socket of locator B and locator C. For the Y-direction deformation of locator B and locator C, ( , , ) represents the target position coordinates in space of the ball socket center of locator B. , , ) represents the target position coordinates of the center of the ball socket of the C locator in space.

[0109] Step 7: Adjust the D positioner according to the real-time feedback value of the X-direction force sensor of the D positioner so that the absolute value of the X-direction force of the C positioner and the D positioner decreases to the threshold. g 3;

[0110] The deformation in the X direction between positioners C and D is calculated by using the real-time feedback value in the X direction from the three-dimensional force sensor. : ;

[0111] in, For the X-direction deformation of the C-positioner and the D-positioner. The distance between the centers of the ball and socket of locator C and locator D. β Let E be the angular deviation between the ball-and-socket direction and the Y direction of the C and D positioners, and let E be the elastic modulus of the component material. The real-time X-axis feedback value of the three-dimensional force sensor of the D-positioner. g 3 represents the threshold value of the absolute value of the X-direction force for both the C-positioner and the D-positioner.

[0112] By obtaining the deformation of the large component and the positional relationship between the C locator and the D locator, the target value that the center of the ball socket of the D locator needs to move to can be calculated, as shown in Formulas 7-1, 7-2 and 7-3.

[0113] (7-1)

[0114] (7-2)

[0115] (7-3)

[0116] in, For the X-direction deformation of the C-positioner and the D-positioner. The distance between the centers of the ball and socket of locator C and locator D is ( , , ) represents the theoretical coordinates of the center of the D-positioner's ball socket in space. , , ) represents the target position coordinates in space of the center of the D locator's ball socket.

[0117] Step 8: Fine-tune the control using a real-time force feedback algorithm to reduce the force on all axes in the X and Y directions to ζ.

[0118] Because the material is rigid, the force values ​​of the other positioners will change after one positioner is moved, so fine-tuning is required through a real-time force feedback control algorithm. The feedback control algorithm is shown in Equation 8-1.

[0119] (8-1)

[0120] in, Let x be the distance that needs to be moved at time k along the x-axis. Let Kp be the distance to move along the y-axis at time k, T be the scaling factor, Ti be the sampling time, and Td be the differentiation time. Let k be the deviation between the real-time feedback value of the force sensor in the x-direction and the target value. Let e ​​be the deviation between the real-time feedback value of the force sensor in the y-direction at time k and the target value. x（k-1） Let e ​​be the deviation between the real-time feedback value of the force sensor in the x-direction at time (k-1) and the target value. y（k-1） Let e ​​be the deviation between the real-time feedback value of the force sensor in the y-direction and the target value at time (k-1). xj e is the deviation between the real-time feedback value in the x-direction at time j during the integration time and the target value. yj The deviation between the real-time feedback value in the y-direction at time j during the integration time and the target value.

[0121] The deviation between the real-time feedback value of the force sensor in the x-direction at time k and the target value The deviation between the real-time feedback value of the force sensor in the y-direction at time k and the target value The following relationship must be satisfied:

[0122] (8-2)

[0123] in, For the three-dimensional force sensor, the force in the x-direction at time k is... For the three-dimensional force sensor, the force in the y-direction at time k is... g These are the threshold values ​​for the X and Y directions of the three-dimensional force sensor.

[0124] Within the elastic limit, the stress on an object is directly proportional to the deformation caused by the stress, as shown in Formula 8-3.

[0125] (8-3)

[0126] The real-time force feedback control algorithm can be obtained through formulas 8-1, 8-2, and 8-3, as shown in formula 8-4.

[0127] (8-4)

[0128] in, This represents the force value in the x-direction of the three-dimensional force sensor at time k. Let F be the force value in the y-direction of the three-dimensional force sensor at time k. x(k-1) The force value in the x-direction at time (k-1) of the three-dimensional force sensor. Let F be the force value in the y-direction of the three-dimensional force sensor at time k. y(k-1) This represents the force value in the y-direction at time (k-1) of the three-dimensional force sensor. g Let be the threshold values ​​in the X and Y directions of the three-dimensional force sensor, T be the sampling time, Ti be the integration time, Td be the differential time, and j be a certain moment in the integration time.

[0129] The real-time force feedback control algorithm is executed iteratively within a specified time until the forces in the X and Y directions decrease to ζ.

[0130] As can be seen, the method provided in this application first requires installing three-dimensional force sensors on four positioners and calibrating the orientation of the force sensors with the assembly coordinate system, ensuring that the X, Y, and Z directions of the four force sensors are parallel to each other. Secondly, a laser tracker is used to measure the position of the ball joint of the large component in the assembly coordinate system as the theoretical position for insertion, controlling the CNC positioners to move the ball sockets on positioners A and B to the theoretical position. Finally, the large component is lifted into place... , Two ball heads are placed in the ball sockets. The position of the B-positioner's X-axis is adjusted based on the real-time X-axis feedback value from the B-positioner's three-dimensional force sensor, causing the absolute value of the X-axis force to decrease to a threshold value. g 1. After adjustment, control the CNC positioner to move the ball joints on the C and D positioners to their theoretical positions. , The two ball joints were hoisted into position. After the entire assembly was in place, the Y-axis positions of the C and D positioners were adjusted based on the Y-feedback values ​​from the three-dimensional force sensors of the C and D positioners, so that the absolute value of the Y-axis force of the four positioners decreased to the threshold. g 2. g 4. Adjust the D positioner based on the real-time feedback value in the X direction from the three-dimensional force sensor so that the absolute values ​​of the force values ​​in the X direction of the C and D positioners decrease to the threshold. g 3. Finally, fine-tuning is performed using a real-time force feedback control algorithm to reduce the force on all axes (X and Y) to the threshold ζ. This utilizes a three-dimensional force sensor to achieve flexible positioning of large components, allowing real-time acquisition of the component's stress during positioning and controlling the positioner's movement based on this stress, thus avoiding or reducing stress tension and compression issues after positioning.

[0131] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A flexible positioning method for large components based on a three-dimensional force sensor, characterized in that, Includes the following steps: The three-dimensional force sensors are installed on each positioner, and the orientation of each three-dimensional force sensor is calibrated with the orientation of the assembly coordinate system so that the X, Y, and Z directions of each three-dimensional force sensor are parallel to each other; the positioner includes positioner A in the lower left corner, positioner B in the upper left corner, positioner C in the upper right corner, and positioner D in the lower right corner. The theoretical placement position of the large component is obtained by measurement, and each of the positioning devices is controlled to move the ball socket on each positioning device to the theoretical position. Large component A was lifted using a hoisting method. ’ Ball head and large component B ’ The ball head is placed in the corresponding ball socket. Based on the real-time X-axis feedback value of the three-dimensional force sensor of the B positioner, the X-axis deformation of the A and B positioners is obtained. ; Based on the X-direction deformation The positional relationship between locator A and locator B is determined to obtain the target position of the ball socket of locator B; the ball socket of locator B is adjusted to the target position; the large component C is hoisted... ’ Ball head and large component D ’ The ball head is placed in the corresponding ball socket; the C positioner is adjusted based on the real-time feedback value of the three-dimensional force sensor in the Y direction of the C positioner, the D positioner is adjusted based on the real-time feedback value of the three-dimensional force sensor in the Y direction of the D positioner, and the D positioner is adjusted based on the real-time feedback value of the three-dimensional force sensor in the X direction of the D positioner; each positioner is finely adjusted based on the preset feedback control algorithm and the real-time feedback value so that the X-direction force value and Y-direction force value of each positioner meet the preset threshold. The X-direction deformation The following relationship must be satisfied: in, Let A and B be the X-direction deformations. This represents the distance between the centers of the ball and socket of locator A and locator B. Let E be the angular deviation between the ball-and-socket directions of positioners A and B and the X direction, and let E be the elastic modulus of the component material. The real-time feedback value of the three-dimensional force sensor in the X direction for the B-positioner. ζ 1 represents the threshold value of the absolute value of the X-axis force of locator A and locator B; The target position of the ball socket of the B locator satisfies the following relationship: in, This represents the distance between the centers of the ball and socket of locator A and locator B. Let A and B be the X-direction deformations of the locator. , , ) represents the theoretical spatial coordinates of the center of the ball socket of locator A. , , ) represents the theoretical spatial coordinates of the ball-and-socket center of locator B. , , Let be the target position coordinates in space of the ball-and-socket center of locator B; where, .

2. The flexible positioning method for large components based on a three-dimensional force sensor according to claim 1, characterized in that, The step of adjusting the C-positioner based on the real-time feedback value of the three-dimensional force sensor in the Y direction includes: Based on the real-time Y-axis feedback value of the three-dimensional force sensor of the C-positioner, the Y-axis deformation of the B-positioners and C-positioners is obtained. ; Based on the Y-direction deformation The positional relationship between locator B and locator C is used to obtain the target position of the ball socket of locator C. Adjust the C-positioner ball socket to the target position of the C-positioner ball socket; The Y-direction deformation The following relationship must be satisfied: in, For the Y-direction deformation of locators B and C, This represents the distance between the centers of the ball and socket of locator B and locator C. Let E be the angular deviation between the ball-and-socket direction and the Y direction of positioners B and C, and let E be the elastic modulus of the component material. The value of the three-dimensional force sensor on the C-positioner about the Y direction. ζ 2 represents the absolute value threshold of the Y-axis force for both positioner B and positioner C; The target position of the ball socket of the C locator satisfies the following relationship: in, This represents the distance between the centers of the ball and socket of locator B and locator C. For the Y-direction deformation of locator B and locator C, ( , , ) represents the target position coordinates in space of the ball-and-socket center of locator B. , , ) represents the target position coordinates in space of the center of the ball socket of the C-positioner; where, .

3. The flexible positioning method for large components based on a three-dimensional force sensor according to claim 1, characterized in that, The step of adjusting the D-positioner based on the real-time feedback value of the three-dimensional force sensor in the Y direction includes: Based on the real-time Y-axis feedback value of the three-dimensional force sensor using the D-positioner, the Y-axis deformation of the A-positioner and the D-positioner is obtained. ; Based on the Y-direction deformation The positional relationship between locator A and locator D is used to obtain the first target position of the ball socket of locator D. Adjust the D-positioner ball socket to the first target position of the D-positioner ball socket; The Y-direction deformation The following relationship must be satisfied: in, For the Y-direction deformation of locator A and locator D, The distance between the centers of the ball and socket of locator A and locator D. Let E be the angular deviation between the ball-and-socket direction and the Y direction of positioners A and D, and let E be the elastic modulus of the component material. The real-time feedback value of the three-dimensional force sensor in the Y direction for the D positioner. ζ 4 represents the absolute value threshold of the Y-axis force for both positioner A and positioner D; The target position of the ball socket of the D locator satisfies the following relationship: in, The distance between the centers of the ball and socket of locator A and locator D. For the Y-direction deformation of positioners A and D, ( , , ) represents the theoretical spatial coordinates of the center of the ball socket of locator A. , , ) represents the theoretical coordinates of the center of the D-positioner's ball socket in space. , , ) represents the calculated target position coordinates of the ball-and-socket center of the D-positioner in space; where, .

4. The flexible positioning method for large components based on a three-dimensional force sensor according to claim 3, characterized in that, The fine-tuning of each locator based on a preset feedback control algorithm and real-time feedback values, so that the X-direction force values ​​and Y-direction force values ​​of each locator meet preset thresholds, includes: After adjusting the ball socket of the D locator to the first target position of the ball socket of the D locator, the X-direction deformation of the C locator and the D locator is obtained based on the real-time X-direction feedback value of the three-dimensional force sensor of the D locator. ; Based on the X-direction deformation The positional relationship between locator C and locator D is used to obtain the second target position of the ball socket of locator D; Adjust the D-positioner ball socket to the second target position of the D-positioner ball socket.

5. The flexible positioning method for large components based on a three-dimensional force sensor according to claim 4, characterized in that, The X-direction deformation The following relationship must be satisfied: in, For the X-direction deformation of the C-positioner and the D-positioner. The distance between the centers of the ball and socket of locator C and locator D. β Let E be the angular deviation between the ball-and-socket direction and the Y direction of the C and D positioners, and let E be the elastic modulus of the component material. The real-time X-axis feedback value of the three-dimensional force sensor of the D-positioner. ζ 3 represents the threshold value of the absolute value of the X-direction force for both the C-positioner and the D-positioner.

6. The flexible positioning method for large components based on a three-dimensional force sensor according to claim 4, characterized in that, The target position of the ball socket of the D locator satisfies the following relationship: in, For the X-direction deformation of the C-positioner and the D-positioner. The distance between the centers of the ball and socket of locator C and locator D is ( , , ) represents the theoretical coordinates of the center of the D-positioner's ball socket in space. , , ) represents the target position coordinates in space of the center of the D-positioner's ball socket; where, .

7. The flexible positioning method for large components based on a three-dimensional force sensor according to claim 1, characterized in that, The preset feedback control algorithm satisfies the following relationship: in, This represents the force value in the x-direction of the three-dimensional force sensor at time k. Let F be the force value in the y-direction of the three-dimensional force sensor at time k. x(k-1) The force value in the x-direction at time (k-1) of the three-dimensional force sensor. Let F be the force value in the y-direction of the three-dimensional force sensor at time k. y(k-1) This represents the force value in the y-direction at time (k-1) of the three-dimensional force sensor. ζ Let be the threshold values ​​in the X and Y directions of the three-dimensional force sensor, T be the sampling time, Ti be the integration time, Td be the differential time, and j be a certain moment in the integration time.

8. The flexible positioning method for large components based on a three-dimensional force sensor according to claim 1, characterized in that, The step of obtaining the theoretical placement position of the large component by measurement and controlling each of the positioners to move the ball sockets on each position to the theoretical position includes: A laser tracker was used for spatial modeling, and the theoretical position of the large component when it was in place was measured; among which, Here are the theoretical positioning coordinates of the ball-and-socket joint of locator A. The coordinates of the ball-and-socket theoretical positioning position of the B-positioner. The coordinates of the C-positioner's ball-and-socket theoretical positioning position are given. The coordinates of the D-positioner's ball-and-socket theoretical insertion position; Based on the theoretical positioning coordinates of the ball sockets of each locator, control each locator to move the ball sockets on each locator to the theoretical position.

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