Assembly element jack pose detection method based on tactile feedback

Abstract

The invention discloses an assembly element jack pose detection method based on tactile feedback, and the method comprises the steps: configuring a bionic finger containing tactile sensitive elements for the tail end of a robot, collecting the voltage signals of all tactile sensitive elements in a plane where an assembly hole is located in a uniform sliding manner, generating a tactile data matrix through filtering, differentiating and weighting, and carrying out the calculation of the tactile data matrix; hole site detection is realized through threshold comparison; coordinates are calculated according to the motion trail of the robot and hole site data, an assembly pose is determined by fusing element geometric features, and finally the robot is guided to adjust the pose to complete a high-precision jack task. The method simulates an exploration perception mode of a human hand in a weak light environment, detects and locates a scene where visual identification is difficult to competent for shaft insertion into a hole, and helps a robot to realize accurate assembly.

Description

Technical Field

[0001] The present invention belongs to the field of robot intelligent perception and operation, and particularly relates to a method for detecting the jacking pose of an assembly component based on tactile feedback. Background Art

[0002] Assembly is an essential link in the production and manufacturing of the vast majority of electromechanical products, such as the assembly of pin-type resistors and capacitors, the insertion of electronic connectors, the installation of multi-pin housings, etc. However, at present, the product assembly is basically completed by manual operation on the assembly line, with high labor costs, insufficient automation, and room for improvement in product consistency. Implementing product assembly using robots has great market potential and application value. However, at present, the movement of robots mostly relies on visual guidance, and the assembly process frequently involves the contact and interaction between mechanical grippers, objects to be assembled, and the surrounding environment. Visual occlusion is too severe to be applied.

[0003] Therefore, in order to improve the adaptability to complex environments in the mechanical assembly process, it is necessary to develop a tactile feedback-based intelligent hole position detection and positioning method for robots to solve the problem that precise assembly cannot be completed under conditions such as severe occlusion during the visual guidance process. Summary of the Invention

[0004] To solve the above problems, the present invention discloses a method for detecting the jacking pose of an assembly component based on tactile feedback, equipping the robot with tactile bionic fingers, simulating the exploration and perception method of the human hand in low-light or dark environments, enhancing its autonomous operation ability in complex and dynamic environments, and improving the working efficiency of the robot in actual production and adapting to diverse assembly tasks through multi-channel collection of sensitive component signals and threshold detection methods.

[0005] To achieve the above object, the technical solution of the present invention is as follows:

[0006] A method for detecting the jacking pose of an assembly component based on tactile feedback, comprising the following steps:

[0007] (1) Fabricate tactile bionic fingers

[0008] The tactile bionic fingers are composed of a flexible skin layer and a rigid phalanx, and the flexible skin layer is embedded with tactile sensitive components for sensing static force and dynamic force;

[0009] (2) Horizontally slide the tactile bionic fingers across the surface to be assembled, detect whether there are mounting holes on the surface to be assembled, and fuse and judge the electrical signals of multiple sensitive components collected synchronously;

[0010] (3) Compare the hole positions detected in the previous step and their distribution relationships with the number of pins and geometric distribution characteristics of the component to be inserted, determine the corresponding hole position combination for the current component, and determine its insertion position based on this hole position combination. The orientation angle of the component in the plane to be assembled is determined by the geometric distribution characteristics of the hole position combination.

[0011] Further, in step (1), the static force tactile sensitive element is made of a piezoresistive material (Strain Gauge, abbreviated as SG), and the dynamic force tactile sensitive element is made of a piezoelectric sensitive element, polyvinylidene fluoride film (Polyvinylidene Difluoride, abbreviated as PVDF), which is used to convert the external tactile signal into an electrical signal.

[0012] The number of tactile sensitive elements in the tactile bionic finger is greater than or equal to 2. The more sensitive elements there are, the higher the recognition accuracy.

[0013] Further, in step (2), the detection method for the installation hole positions is as follows:

[0014] S0: The component has pins with known quantity, size parameters, and geometric distribution characteristics, and there are multiple groups of assembly holes with unknown positions and orientation angles but with quantity, size parameters, and geometric distribution characteristics matching those of the above component on the surface to be assembled. The pins of the component and the assembly holes are precisely assembled at appropriate positions and orientation angles.

[0015] S1: Select a suitable origin and orientation angle in the above surface to be assembled to establish a plane rectangular coordinate system. Specifically, divide m parallel sliding paths parallel to the X-axis at equal intervals along the Y-axis direction. Control the robotic tactile bionic finger to slide across the plane to be assembled along the above m sliding paths in the order of increasing Y coordinates, and simultaneously collect the tactile (voltage) signals of n sensitive element channels in the tactile bionic finger, and store the tactile signals in the original signal matrix M1. The matrix element x ij represents the tactile signal collected by the robotic tactile bionic finger on the i-th channel and the j-th sliding path, that is:

[0016]

[0017] S2: Perform differential, smoothing filtering, and normalization processing on the collected tactile signals in sequence, and perform weighted summation on the processing results of n channels. The summation result X j of the j-th sliding path is as follows:

[0018] X j = w1x 1j + w2x 2j +…+ w n x nj

[0019] In the above formula, w n represents the weight coefficient of the nth channel. The magnitude of the weight coefficient is determined by the type of the sensing element and its spatial distribution state in the finger. Store the above summation result in matrix M2, and the element X j represents the tactile signal collected on the jth sliding path after the above processing:

[0020] M2 = [X1, X2, …, X j , …, X m

[0021] Perform weighted summation processing on the data of each channel of the sensing element. The magnitude of the weight coefficient is determined by the type of the sensing element and its spatial distribution in the finger. Generally, the more sensitive the tactile sensing element is to the external tactile signal, the larger the corresponding weight coefficient is.

[0022] S3: Detect and screen out the signal segments collected when the tactile bionic finger slides above the assembly hole in the X j signal.

[0023] Specifically, the detection of the hole position is realized by threshold comparison, where the screening threshold represents the mean value of the signal X j , σ represents the standard deviation of the signal X j , and k is the threshold ratio coefficient, which is obtained from preliminary experiments.

[0024] In the preliminary experiment, it is necessary to control the tactile fingertip to repeatedly slide above the assembly hole. It can be observed that the amplitude of the tactile signal will change significantly when the tactile fingertip slides above the assembly hole. By continuously adjusting the threshold coefficient k, the computer can accurately capture the corresponding signal change, and the corresponding k value is the appropriate threshold coefficient.

[0025] Let t be the index value of the tactile signal sequence X j . Compare X j with the threshold F. The signal segments that satisfy X j (t) ≤ F can be regarded as the tactile signals collected when the tactile bionic finger slides above the assembly hole. Cut out the signal segments that meet the above comparison results and store them in matrix M3 in segments. Among them, the element a ij represents the ith signal segment detected when sliding on the jth sliding path, and c represents the maximum number of assembly holes detected under a single sliding path:

[0026]

[0027] Furthermore, in step (3), the method for realizing the positioning of the assembly hole and the autonomous assembly of the components is as follows:

[0028] S4: Determine the X coordinate of the assembly hole​

[0029] Specifically, for the tactile signals collected on a single sliding path, the minimum value in each valid signal segment in the matrix M3 is regarded as the tactile signal collected when the tactile bionic finger slides across the center of the assembly hole, the index value corresponding to the minimum value is extracted, and the X coordinates of the centers of the assembly holes passed by the current sliding path are calculated in combination with the sliding speed of the tactile fingertip and the sampling rate of the tactile sensitive element. Repeat the above steps to process the tactile signals of each sliding path until the X coordinates of the centers of the assembly holes under all m sliding paths are screened and calculated.

[0030] S5: Considering that the tactile fingertip may repeatedly touch the same assembly hole under different sliding trajectories, thereby calculating repeated X-coordinate values, it is necessary to introduce a threshold judgment method to eliminate the calculation of repeated X-coordinate values. Specifically, the threshold x0 is introduced. When the difference in the X-coordinates of the assembly holes calculated under different sliding paths is less than the threshold x0, these similar X-coordinates are regarded as the coordinate values ​​of the same assembly hole or assembly holes with the same X-coordinates. Take the weighted average of all the above similar X-coordinate values ​​to replace all repeated X-coordinate values, and further, store the X-coordinate values ​​of the eliminated duplicate data in the array point_x from small to large.

[0031] S6: Determine the Y coordinate value of the assembly hole. Specifically, plan a path parallel to the Y axis through the X position represented by each element of the array point_x. Control the robot to slide across the plane to be measured in the direction of increasing Y coordinates, and process the collected signals according to S1 to S4 to obtain the Y coordinate point_y of the assembly hole.

[0032] S7: Determine the component assembly information. Specifically, according to the X-coordinate array point_x and the Y-coordinate array point_y collected above, the coordinate positions of the centers of each assembly hole on the plane are combined in sequence. The assembly holes on the plane are grouped according to the number of pins, size parameters and geometric distribution characteristics of the components, and the geometric center and direction angle inside each group of assembly holes in the assembly plane are calculated. According to the center position and geometric inclination of each group of assembly holes, the robot arm is driven to assemble the components into each group of assembly holes at a suitable angle, thereby completing the autonomous assembly task of the components.

[0033] The intelligent detection and positioning method is not limited to the insertion of single-pin, double-pin and triple-pin components, but is also applicable to the shaft-in-hole assembly of more pin components on a plane.

[0034] The beneficial effects of the present invention are as follows:

[0035] The present invention proposes a concise algorithm, which uses filtering denoising, threshold judgment and other methods to determine the position of the hole, and is compatible with the field of robot assembly.

[0036] The present invention can perform weighted summation on the data of tactile sensitive elements, making full use of the advantages of multi-channel information fusion, avoiding the influence of data fluctuations of a single sensitive element on the results, and helping to improve assembly accuracy. At the same time, by estimating the minimum distance between holes, the situation of sliding through the same hole multiple times is eliminated, making the results more accurate. In this way, the position of the hole can be accurately identified to ensure a higher degree of matching between the parts and the holes, thereby greatly improving the accuracy of robot assembly and reducing product quality problems caused by assembly errors. For example, in the assembly of automotive parts, bolts can be accurately inserted into screw holes of matching shapes to avoid loosening or misalignment.

[0037] The present invention can enhance the autonomy and adaptability of the robot. When faced with assembly tasks in different assembly environments, the tactile signal recognition algorithm can assist the robot to autonomously adjust the assembly strategy to adapt to diverse production needs. For example, when determining the position of unknown plate assembly holes, the collection of tactile signals overcomes the difficulties that may exist in observation and quantitative measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 The figure is a flow chart of the algorithm of the identification method of the present invention.

[0039] Figure 2 It is a schematic diagram of the tactile bionic finger structure and a flow chart of hole position detection in the present invention.

[0040] In the figure: 10, flexible material layer; 20, rigid phalanges

[0041] Figure 3 Schematic diagram of a test device according to an example of the present invention.

[0042] In the figure: 1. Components to be assembled; 2. Plane to be tested; 3. Assembly holes to be tested; 4. Tactile fingertips; 5. Mechanical grippers; 6. Mechanical arms; 7. Single assembly holes to be tested; 8. Double assembly holes to be tested; 9. Triple assembly holes to be tested

[0043] a~d, four tactile fingertips sliding paths along the X-axis with equal spacing; e~h, four sliding paths along the Y-axis. DETAILED DESCRIPTION

[0044] The present invention will be further explained below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0045] A method for detecting the position and posture of an assembly component socket based on tactile feedback comprises the following steps:

[0046] (1) Making tactile bionic fingers

[0047] The tactile bionic finger is composed of a flexible skin layer and rigid phalanges, and the flexible skin layer is embedded with tactile sensitive elements that sense static and dynamic forces;

[0048] (2) The tactile bionic finger tip 4 is moved parallel to the plane to be measured 2 to detect whether there is a mounting hole on the plane to be measured 2, and the electrical signals of multiple sensitive elements collected synchronously are integrated and judged;

[0049] (3) Compare the hole positions and their distribution relationship detected in the previous step with the number of pins and geometric distribution characteristics of the components to be inserted, determine the hole position combination corresponding to the current component, determine its insertion position based on the hole position combination, and the orientation angle of the component in the plane to be assembled is determined by the geometric distribution characteristics of the hole position combination.

[0050] Specifically, in step (1), if Figure 2 The robot tactile fingertip shown in the figure adopts a hybrid structure of flexible skin layer-tactile sensing layer-rigid finger bone. It integrates multiple dynamic force tactile sensitive elements made of polyvinylidene fluoride film (PVDF) and static force tactile sensitive elements made of resistive strain gauge (SG) to convert external tactile signals into electrical signals.

[0051] Specifically, the outermost flexible skin layer is composed of silicone, which can transmit external static force signals (pressure) and dynamic force signals (vibration) to the internal sensitive elements more completely.

[0052] Specifically, in this design, one side of the static force tactile sensitive element is embedded in the flexible skin layer, and the other side is close to the rigid phalanges; both sides of the dynamic force tactile sensitive element are in contact with the flexible layer, and are all embedded in the flexible material, without contacting the rigid phalanges. Under the above design, one side of the static force tactile sensitive element is supported by the rigid phalanges. Compared with the flexible material, the rigid phalanges have the advantage of smaller vibration amplitude, which can reduce the influence of the vibration signal of the flexible material layer on the static force tactile sensitive element, and is more conducive to the static force tactile sensitive element to collect static pressure signals; the dynamic force tactile sensitive element that is completely embedded in the flexible material layer has no rigid material for support, and the vibration signal of the flexible material can directly act on the dynamic force tactile sensitive element, which is more conducive to the dynamic force tactile sensitive element to collect vibration signals.

[0053] Specifically, in step (2), the method for realizing hole position detection is:

[0054] S0: The component has pins with known quantity, size parameters and geometric distribution characteristics, and correspondingly distributed on the plane to be assembled are multiple groups of assembly holes with unknown positions and orientation angles, but whose quantity, size parameters and geometric distribution characteristics match those of the above components. The pins of the components can be accurately assembled with the assembly holes at appropriate positions and orientation angles.

[0055] Specifically, there are a single assembly hole 7, a double assembly hole 8 with different hole spacings L1 and L2, and a triple assembly hole 9 with equal hole spacings on the tested plate. At the same time, the number, size parameters and geometric distribution characteristics of the components are consistent with the small holes to be tested.

[0056] S1: Select a suitable origin and direction angle in the above-mentioned plane to be assembled to establish a plane rectangular coordinate system. Specifically, m sliding paths parallel to the X-axis are equally spaced along the Y-axis direction, and the robot's tactile bionic finger is controlled to slide along the m sliding paths in the order of increasing Y coordinates across the plane to be measured 2, while collecting the tactile (voltage) signals of the n sensitive element channels in the tactile bionic finger, and storing the tactile signals in the original signal matrix M1. The matrix element x ij represents the tactile signal collected by the robot's tactile bionic finger on the i-th channel and the j-th sliding path, that is:

[0057]

[0058] S2: The collected tactile signals are differentiated, smoothed and normalized in turn, and the processing results of n channels are weighted summed, where the summation result X of the hth sliding path is j as follows:

[0059] X j =w1x 1j +w2x 2j +…+w n x nj

[0060] Specifically, in the above formula, w n represents the weight coefficient of the nth channel. The size of the weight coefficient is determined by the type of sensitive element and its spatial distribution in the finger. The above summation result is stored in the matrix M2, and the element X j It represents the tactile signal collected on the jth sliding path after the above processing:

[0061] M2=[X1,X2,…,X j ,…,X m ]

[0062] Specifically, the more sensitive the tactile sensitive element is to the external tactile signal, the greater the corresponding weight coefficient is.

[0063] Specifically, in this experiment, the PVDF dynamic force sensitive unit responds more to the vibration signal of the flexible material during the sliding of the tactile finger and has a larger weight coefficient.

[0064] S3: Further, in X j The signal segment collected when the tactile bionic finger slides over the assembly hole is detected and screened out from the signal. Specifically, the hole position is detected by threshold comparison, wherein the screening threshold Represents signal X j The mean of the signal X j The standard deviation of , k is the threshold ratio coefficient, obtained from the preliminary experiment. Let t be the tactile signal sequence X j The index value of X j Compare with the threshold F, satisfy X j The signal segments where (t)≤F can be regarded as the tactile signals collected when the tactile bionic finger slides over the assembly hole. The signal segments that meet the above comparison results are cut out and stored in the matrix M3 in segments. ij represents the i-th signal segment detected when sliding on the j-th sliding path, and c represents the maximum number of assembly holes detected under a single sliding path:

[0065]

[0066] Specifically, when the tactile fingertip 4 slides at a constant speed on the plane 2 to be measured, the surface layer of the flexible material directly slides relative to the plate, and is simultaneously subjected to the effects of static force (pressure) and dynamic force (vibration). The voltage signal remains stable at a constant speed. After encountering a small hole, the contact area between the surface of the flexible material and the plate decreases, and the static force (pressure) and dynamic force (vibration) suddenly change. After differential processing in step S2, the voltage signal shows a downward trend. Therefore, X is satisfied. j The signal segment with (t)≤F can be regarded as the tactile signal collected when the tactile bionic finger slides over the assembly hole, where there is a small hole.

[0067] Specifically, the threshold proportionality coefficient k needs to be obtained from a preliminary experiment. In the preliminary experiment, the tactile fingertip needs to be controlled to repeatedly slide over the assembly hole. It can be observed that the amplitude of the tactile signal will change significantly when the tactile fingertip slides over the assembly hole. By continuously adjusting the threshold coefficient k, the computer can accurately capture the corresponding signal changes, and the corresponding k value is the appropriate threshold coefficient.

[0068] Specifically, in step (3), the method for realizing assembly hole positioning and component autonomous assembly is:

[0069] S4: Determine the X coordinate of the assembly hole.

[0070] Specifically, for the tactile signals collected on a single sliding path, the minimum value in each valid signal segment in the matrix M3 is regarded as the tactile signal collected when the tactile bionic finger slides across the center of the assembly hole, the index value corresponding to the minimum value is extracted, and the X coordinates of the centers of the assembly holes passed by the current sliding path are calculated in combination with the sliding speed of the tactile fingertip and the sampling rate of the tactile sensitive element. Repeat the above steps to process the tactile signals of each sliding path until the X coordinates of the centers of the assembly holes under all m sliding paths are screened and calculated.

[0071] S5: Eliminate the repeated X coordinate values. Specifically, a threshold x0 is introduced. When the difference of the X coordinates of the assembly holes calculated under different sliding paths is less than the threshold x0, these similar X coordinates are regarded as the coordinate values ​​of the same assembly hole or the assembly holes with the same X coordinates. The weighted average of all the similar X coordinate values ​​is taken to replace all the repeated X coordinate values. Furthermore, the X coordinate values ​​of the eliminated duplicate data are stored in the array point_x from small to large.

[0072] Specifically, considering that the tactile fingertip may repeatedly touch the same assembly hole under different sliding trajectories, thereby calculating repeated X-coordinate values, it is necessary to introduce a threshold judgment method to eliminate and merge the above redundant data.

[0073] Specifically, Figure 3 In the sliding paths a~d parallel to the X-axis, which are equally divided along the Y-axis direction, when the fingertip moves along the sliding paths c and d, extremely similar X-coordinate values ​​of the small holes will be obtained through the judgment and calculation of the S1~S4 methods. In order to ensure the accuracy of the assembly hole position information, the threshold x0 is introduced to eliminate the X-coordinate values ​​of the repeated hole positions. The threshold x0 is determined by the minimum inner diameter of the assembly hole in the experiment.

[0074] S6: Determine the Y coordinate value of the assembly hole. Specifically, plan a path parallel to the Y axis through the X position represented by each element of the array point_x. Control the robot to slide across the plane to be measured in the direction of increasing Y coordinates, and process the collected signals according to S1 to S4 to obtain the Y coordinate point_y of the assembly hole.

[0075] Specifically, in the four tactile fingertip sliding paths a to d, after the judgment and calculation of S1 to S5, the array point_x has recorded the X coordinate of the small hole in the process, and the tactile fingertip is controlled to slide along the path parallel to the Y axis at the position where the X coordinate exists, and the collected signal is processed according to S1 to S4 to obtain the Y coordinate point_y of the assembly hole.

[0076] S7: Determine the component assembly information. Specifically, according to the X-coordinate array point_x and the Y-coordinate array point_y collected above, the coordinate positions of the centers of each assembly hole on the plane are combined in sequence. The assembly holes on the plane are grouped according to the number of pins, size parameters and geometric distribution characteristics of the components, and the geometric center and direction angle inside each group of assembly holes in the assembly plane are calculated. According to the center position and geometric inclination of each group of assembly holes, the robot arm is driven to assemble the components into each group of assembly holes at a suitable angle, thereby completing the autonomous assembly task of the components.

[0077] It should be noted that the above content only illustrates the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications all fall within the protection scope of the claims of the present invention.

Claims

1. A method for detecting the position and posture of an assembly component socket based on tactile feedback, characterized in that: The following steps are involved: (1) Making tactile bionic fingers The tactile bionic finger is composed of a flexible skin layer and rigid phalanges, and the flexible skin layer is embedded with tactile sensitive elements that sense static and dynamic forces; (2) By sliding the tactile bionic finger across the surface to be assembled in parallel, it is detected whether there are installation holes on the surface to be assembled, and the electrical signals of multiple sensitive components collected synchronously are integrated and judged; (3) Compare the hole positions and their distribution relationship detected in the previous step with the number of pins and geometric distribution characteristics of the components to be inserted, determine the hole position combination corresponding to the current component, determine its insertion position based on the hole position combination, and the orientation angle of the component in the plane to be assembled is determined by the geometric distribution characteristics of the hole position combination.

2. The method for detecting the position and posture of an assembly component socket based on tactile feedback according to claim 1, characterized in that: The outermost flexible material layer in step (1) is made of silicone, the static force tactile sensitive element is made of piezoresistive material, and the dynamic force tactile sensitive element is made of piezoelectric sensitive element.

3. The method for detecting the position and posture of an assembly component socket based on tactile feedback according to claim 1, characterized in that: Step (1) One side of the static force tactile sensitive element is embedded in the flexible skin layer, and the other side is in close contact with the rigid phalanges; both sides of the dynamic force tactile sensitive element are in contact with the flexible layer, and are all embedded in the flexible material without contacting the rigid phalanges.

4. The method for detecting the position and posture of an assembly component socket based on tactile feedback according to claim 1, characterized in that: In step (2), the method for realizing hole position detection is: S0: The component has pins with known quantity, size parameters and geometric distribution characteristics, and correspondingly, there are multiple groups of assembly holes with unknown positions and orientation angles, but the quantity, size parameters and geometric distribution characteristics match those of the component, and the pins of the component can be accurately assembled with the assembly holes at appropriate positions and orientation angles; S1: Select a suitable origin and direction angle in the above-mentioned plane to be assembled to establish a plane rectangular coordinate system; Specifically, m sliding paths parallel to the X axis are equally spaced along the Y axis, and the robot's tactile bionic finger is controlled to slide along the m sliding paths in the order of increasing Y coordinates over the plane to be assembled, while collecting tactile signals of n sensitive element channels in the tactile bionic finger, and storing the tactile signals in the original signal matrix M1; the matrix element x ij represents the tactile signal collected by the robot's tactile bionic finger on the i-th channel and the j-th sliding path, that is: S2: The collected tactile signals are differentiated, smoothed and normalized in turn, and the processing results of n channels are weighted summed, where the summation result X of the jth sliding path is j as follows: X j =w1x 1j +w2x 2j +…+w n x nj In the above formula, w n represents the weight coefficient of the nth channel. The size of the weight coefficient is determined by the type of sensitive element and the spatial distribution state in the finger. The above summation result is stored in the matrix M2. The element X j It represents the tactile signal collected on the jth sliding path after the above processing: M2=[X1,X2,…,X j ,…,X m ] S3: Further, in X j Detect and filter out the signal fragments collected when the tactile bionic finger slides over the assembly hole Specifically, the hole position is detected by threshold comparison, where the screening threshold Represents signal X j The mean of the signal X j The standard deviation of k is the threshold ratio coefficient obtained from the preliminary experiment; let t be the tactile signal sequence X j The index value of X j Compare with the threshold F, satisfy X j The signal segments where (t)≤F are regarded as the tactile signals collected when the tactile bionic finger slides over the assembly hole. The signal segments that meet the above comparison results are cut out and stored in the matrix M3 in segments; the element a ij represents the i-th signal segment detected when sliding on the j-th sliding path, and c represents the maximum number of assembly holes detected under a single sliding path:

5. The method for detecting the position and posture of an assembly component socket based on tactile feedback according to claim 1, characterized in that: In step (3), the method for realizing assembly hole positioning and component autonomous assembly is: S4: Determine the X coordinate of the assembly hole Specifically, for the tactile signal collected on a single sliding path, the minimum value in each valid signal segment in the matrix M3 is regarded as the tactile signal collected when the tactile bionic finger slides over the center of the assembly hole, the index value corresponding to the above minimum value is extracted, and the X coordinates of the centers of each assembly hole passed by the current sliding path are calculated in combination with the sliding rate of the tactile fingertip and the sampling rate of the tactile sensitive element; the above steps are repeated to process the tactile signal of each sliding path until the X coordinates of the centers of the assembly holes under all m sliding paths are screened and calculated; S5: Eliminate calculation of duplicate X coordinate values Specifically, a threshold x0 is introduced. When the difference of the X coordinates of the assembly holes calculated under different sliding paths is less than the threshold x0, these similar X coordinates are regarded as the coordinate values ​​of the same assembly hole or the assembly holes with the same X coordinates. The weighted average of all the similar X coordinate values ​​is taken to replace all the repeated X coordinate values. Furthermore, the X coordinate values ​​of the eliminated duplicate data are stored in the array point_x from small to large. S6: Determine the Y coordinate value of the assembly hole Specifically, a path parallel to the Y axis is planned through the X position represented by each element of the array point_x; the robot is controlled to slide across the plane to be measured in the direction of increasing Y coordinate, and the collected signal is processed according to S1 to S4 to obtain the Y coordinate point_y of the assembly hole; S7: Determine component assembly information Specifically, according to the X-coordinate array point_x and the Y-coordinate array point_y collected above, the coordinate positions of the centers of each assembly hole on the plane are sequentially combined; the assembly holes on the plane are grouped according to the number of pins, size parameters and geometric distribution characteristics of the components, and the geometric center inside each group of assembly holes and the direction angle in the assembly plane are calculated. According to the center position and geometric inclination angle of each group of assembly holes, the robot arm is driven to assemble the components into each group of assembly holes at a suitable angle to complete the autonomous assembly task of the components.

6. The method for detecting the position and posture of an assembly component socket based on tactile feedback according to claim 4, characterized in that: In step S2, the data of each channel of the sensitive element are weighted and summed, and the size of the weight coefficient is determined by the type of the sensitive element and the spatial distribution in the finger; The more sensitive the tactile sensitive element is to the external tactile signal, the greater the corresponding weight coefficient is.

7. The method for detecting the position and posture of an assembly component socket based on tactile feedback according to claim 4, characterized in that: In step S3, the threshold proportionality coefficient k needs to be obtained from preliminary experiments. In the preliminary experiment, the tactile fingertip needs to be controlled to repeatedly slide over the assembly hole. It is observed that the amplitude of the tactile signal will change significantly when the tactile fingertip slides over the assembly hole. By continuously adjusting the threshold coefficient k, the computer can accurately capture the corresponding signal changes. The corresponding k value is the appropriate threshold coefficient.

8. The method for detecting the position and posture of an assembly component socket based on tactile feedback according to claim 5, characterized in that: In step S5, considering that the tactile fingertip may repeatedly touch the same assembly hole under different sliding trajectories, thereby calculating repeated X coordinate values, a threshold judgment method needs to be introduced to eliminate and merge the above redundant data.

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