A flexible contact slip detection device and detection method

Abstract

The invention relates to the technical field of detection devices, and discloses a flexible contact slip detection device and a detection method. The flexible contact slip detection device comprises a detection platform, a computer arranged on the detection platform, a high-speed camera arranged on one side of the detection platform, and a detection mechanism arranged on the detection platform. The detection mechanism comprises a stand, a slide seat is slidably mounted on the stand, a driving component for driving the slide seat to rise and fall is arranged on the stand, a clamping component for clamping a sample is arranged on the slide seat, and a support tube is arranged on one side of the stand. The invention accurately reproduces the dynamic load characteristics when the fruit stalk is detached through the synergistic effect of a spring elastic system and a limit component, the compression process of the first spring can linearly simulate the biomechanical response of the fruit stalk when it is stretched, and when the pulling force reaches a preset threshold, the instantaneous release mechanism of the limit component accurately restores the dynamic impact process of the fruit stalk breaking, so that the detection environment is highly consistent with the mechanical characteristics of the actual picking scene.

Description

Technical Field

[0001] The present invention relates to the technical field of detection devices, and in particular to a flexible contact slip detection device and a detection method. Background Art

[0002] The slip sensor can be integrated into the robot arm or picking tool to accurately sense the contact status and slip trend between the robot and the fruit, ensuring accurate positioning and stable grasping at the moment of picking. The flexible contact slip detection device is a sensor system used to monitor and measure the relative slip between objects. It can detect the relative movement of the contact surface in real time and provide key feedback information for robot grasping, manipulation and other tasks. This device usually has the characteristics of high precision, high sensitivity and fast response, and can accurately determine the occurrence of slip without damaging the object and predict the slip trend.

[0003] The slip sensor is generally set on the clamp, and a flexible anti-slip pad is set on the clamp. Existing laboratory testing equipment usually uses the following method to evaluate the clamping performance of the flexible anti-slip pad: the fruit to be tested is placed on the test platform, and clamped by a clamp equipped with a flexible anti-slip pad. At the same time, a high-speed camera is used to record the three-dimensional displacement changes during the clamping process in real time. The collected images are analyzed based on computer vision algorithms, and the slip vector of the fruit relative to the clamp can be accurately calculated, thereby quantitatively evaluating the anti-slip properties of different flexible materials.

[0004] However, there are essential differences in actual orchard picking scenarios: the picking process needs to overcome the detachment resistance caused by the biomechanical properties of the fruit stems, which will cause the clamping system to be subjected to dynamic load impacts. The existing detection schemes lack mechanical simulation of the fruit stem detachment process, resulting in reduced accuracy of detection results.

[0005] Therefore, it is necessary to provide a flexible contact slip detection device and a detection method to solve the above technical problems. Summary of the invention

[0006] The purpose of the present invention is to provide a flexible contact slip detection device and detection method, in which the detection environment is highly consistent with the mechanical characteristics of the actual picking scene, and the comprehensiveness of the performance evaluation of the anti-slip pad is significantly improved.

[0007] The above technical objectives of the present invention are achieved through the following technical solutions: a flexible contact slip detection device, comprising a detection platform, a computer arranged on the detection platform, a high-speed camera arranged on one side of the detection platform and a detection mechanism arranged on the detection platform, the detection mechanism comprising a stand, a slide seat is slidably mounted on the stand, a driving component for driving the slide seat to rise and fall is arranged on the stand, a clamping component for clamping the sample is arranged on the slide, a support tube is arranged on one side of the stand, the support tube is arranged directly above the clamping component, a chuck, a connecting column and a limit plate are arranged in the support tube, the connecting column passes through the chuck, and the connecting column and the chuck are slidably matched, the limit plate is fixedly connected to the top end of the connecting column, the limit plate and the chuck are elastically connected by a first spring, a fixing component for fixing the sample is installed at the bottom end of the connecting column, and a limiting component for limiting the chuck is arranged on the support tube.

[0008] The present invention is further configured as follows: the driving assembly includes a mounting frame, a motor fixedly mounted on the mounting frame, and a driving screw rotatably mounted on the stand, the mounting frame is fixedly mounted on the top of the front side of the stand, the output end of the motor is fixedly connected to the top end of the driving screw, the driving screw passes through the slide seat, and the driving screw is threadedly connected to the slide seat.

[0009] The present invention is further configured as follows: the limit assembly includes a support plate, the support plate is fixedly mounted on the support cylinder, the bottom of the inner side of the support plate is provided with a second slide groove, the inner side of the second slide groove is slidingly provided with a stop block for limiting the chuck. The support plate is provided with a first slide groove, the inner side of the first slide groove is longitudinally slidably mounted with a sliding block, the top of the sliding block is rotatably mounted with an adjusting screw, the adjusting screw penetrates the top wall of the support plate, and the adjusting screw is threadedly connected to the support plate, the inner side of the sliding block is transversely slidably mounted with a driving block, one end of the driving block extends into the inner side of the support cylinder, and the top of the end of the driving block extending into the support cylinder is provided with an inclined surface, a transmission rod is provided on one side of the support plate, the transmission rod is provided with a fourth slide groove, one end of the driving block extends into the fourth slide groove, and the driving block and the fourth slide groove slide up and down in cooperation.

[0010] The present invention is further configured as follows: a first sliding column is fixedly connected to one side of the stop block, one end of the first sliding column is fixedly connected to the transmission rod, a third sliding groove is opened on the support plate, a second sliding column is slidably arranged in the third sliding groove, one end of the second sliding column is fixedly connected to the transmission rod, and the other end of the second sliding column is elastically connected to the inner wall of the third sliding groove through a second spring.

[0011] The present invention is further configured as follows: the fixing assembly includes an installation box, the installation box is fixedly installed at the bottom end of the connecting column, a winding roller is rotatably installed in the installation box, an elastic fixing belt is wound around the winding roller, an end of the elastic fixing belt is fixedly connected to a connecting seat, the connecting seat is located on one side of the installation box, a slot is provided on the other side of the installation box, a card block is provided on the connecting seat, and when the connecting seat is inserted into the slot, the connecting seat is connected to the slot by the card block.

[0012] The present invention is further configured as follows: a mounting cylinder is fixedly installed at one end of the mounting box, one end of the winding roller extends into the mounting cylinder, a mainspring is arranged in the mounting cylinder, one end of the mainspring is fixedly connected to the winding roller, and the other end of the mainspring is fixedly connected to the inner wall of the mounting cylinder, one end of the winding roller away from the mounting cylinder passes through the side wall of the mounting box, and one end of the winding roller away from the mounting cylinder is fixedly sleeved with a second gear, one end of the connecting seat is fixedly installed with a second rack, the second rack is adapted to the second gear, and when the connecting seat is inserted into the slot, the second rack meshes with the second gear and drives the second gear to rotate, so that the winding roller rotates in the direction of tightening the elastic fixing band.

[0013] The present invention is further configured as follows: a connecting plate is fixedly mounted on one side of the mounting frame, a connecting frame is fixedly sleeved on the supporting tube, and the connecting frame is connected to the connecting plate via a tension sensor.

[0014] The present invention is further configured as follows: the clamping assembly includes a guide rail and two clamping plates slidably mounted on the guide rail, and a flexible anti-skid pad is detachably mounted on one side of the two clamping plates close to each other, and a slip sensor is arranged inside the flexible anti-skid pad.

[0015] The present invention is further configured as follows: two first racks are slidably provided on the guide rail, the ends of the two first racks are respectively fixedly connected to the two slide seats, a first gear is rotatably provided in the middle of the guide rail, the two first racks are both meshed with the first gear, a driving element is installed on the slide seat, and the driving element is transmission-connected to the first gear.

[0016] A flexible contact slip detection method, using the above-mentioned flexible contact slip detection device, comprises the following steps:

[0017] S1. Fixing the simulated picked fruit on the fixed component, driving the slide to move by the driving component so that the fruit is located inside the clamping component, and then clamping the fruit by the clamping component;

[0018] S2. The clamping assembly is driven to move downward by the slide seat, and the clamped fruit is driven to move downward when the clamping assembly moves downward. When the fruit moves downward, the limit plate is driven to move downward through the connecting column, thereby compressing the first spring, so that the pulling force of the connecting column on the fruit gradually increases. When the pulling force reaches the pulling force of the fruit stem when picking the fruit, the limit assembly releases the limit on the chuck, so that the chuck can move downward. Finally, with the movement of the clamping assembly, the limit plate and the chuck are both moved out from the inside of the support tube, thereby accurately simulating the process of pulling off the fruit stem when picking the fruit;

[0019] S3. During the inspection process, photos are taken by a high-speed camera and processed by a computer to observe the slippage of the clamping contact surface during the clamping process.

[0020] In summary, the present invention has the following beneficial effects: the present invention accurately reproduces the dynamic load characteristics when the fruit stalk is detached through the synergistic effect of the spring elastic system and the limit component, the compression process of the first spring can linearly simulate the biomechanical response of the fruit stalk when it is stretched, and when the tension reaches the preset threshold, the instantaneous release mechanism of the limit component accurately restores the dynamic impact process of the fruit stalk breaking, so that the detection environment is highly consistent with the mechanical characteristics of the actual picking scene; on the basis of retaining the three-dimensional displacement detection of the high-speed camera, the dynamic collection of the mechanical parameters of the fruit stalk fracture is newly added, and the dynamic load curve in the clamping process can be synchronously obtained through the correlation calculation of the spring deformation and the tension value, and the "mechanical-displacement" two-dimensional evaluation system is constructed in combination with the slip vector data, which significantly improves the comprehensiveness of the performance evaluation of the anti-slip gasket; by simulating the load mutation at the moment of fruit stalk breaking, the anti-slip retention ability of the flexible anti-slip gasket under dynamic impact is effectively verified. Compared with the static clamping test, this scheme can more truly reflect the degradation law of the anti-slip performance of the material under extreme working conditions of orchard picking. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention;

[0022] Figure 2 It is a structural schematic diagram of the detection mechanism of the present invention;

[0023] Figure 3 It is a structural schematic diagram of the support tube, the support plate and the fixing assembly of the present invention;

[0024] Figure 4 It is a cross-sectional structural schematic diagram of the support tube of the present invention;

[0025] Figure 5 It is a structural schematic diagram of the limiting assembly of the present invention;

[0026] Figure 6 It is a schematic structural diagram of the clamping assembly of the present invention;

[0027] Figure 7 It is a structural schematic diagram of the fixing assembly of the present invention;

[0028] Figure 8 It is a schematic diagram of the structure of the winding roller and the mounting cylinder of the present invention;

[0029] Fig. 9 This is a schematic structural diagram of the fixing assembly of the present invention when fixing fruits.

[0030] In the figure: 1, test bench; 2, high-speed camera; 3, computer; 4, stand; 5, drive screw; 6, mounting frame; 7, motor; 9, slide seat; 10, guide rail; 11, clamping plate; 12, flexible anti-skid pad; 13, first gear; 14, first rack; 15, driving element; 16, connecting plate; 17, connecting frame; 18, tension sensor; 19, support cylinder; 20, support plate; 2001, first slide slot; 2002, second slide slot; 2003, third slide slot; 21, Block; 22, first slide column; 23, slider; 24, drive block; 25, adjusting screw; 26, transmission rod; 2601, fourth slide groove; 27, second slide column; 28, second spring; 29, installation box; 2901, slot; 30, winding roller; 31, elastic fixing belt; 32, connecting seat; 3201, clamping block; 33, second rack; 34, second gear; 35, installation cylinder; 36, spring; 37, chuck; 38, limit plate; 39, first spring; 40, connecting column. DETAILED DESCRIPTION

[0031] The present invention will be further described below with reference to the accompanying drawings in the embodiments of the present invention.

[0032] See also Figure 1 to Figure 6In an embodiment of the present invention, a flexible contact slip detection device includes a detection platform 1, a computer 3 arranged on the detection platform 1, a high-speed camera 2 arranged on one side of the detection platform 1, and a detection mechanism arranged on the detection platform 1. The high-speed camera 2 is connected to the computer 3 by signal, so that the picture taken by the high-speed camera 2 can be transmitted to the computer 3 in real time. The detection mechanism includes a stand 4, a slide 9 is slidably mounted on the stand 4, a driving component for driving the slide 9 to rise and fall is arranged on the stand 4, and a clamping member for clamping the sample is arranged on the slide 9. Component, the sample refers to the fruit that needs to be picked for testing, a support tube 19 is provided on one side of the stand 4, the support tube 19 is arranged just above the clamping component, a chuck 37, a connecting column 40 and a limit plate 38 are arranged in the support tube 19, the connecting column 40 passes through the chuck 37, and the connecting column 40 and the chuck 37 are slidably matched, the limit plate 38 is fixedly connected to the top of the connecting column 40, a first spring 39 is sleeved on the connecting column 40, the limit plate 38 and the chuck 37 are elastically connected through the first spring 39, the connecting column A fixing assembly for fixing the sample is installed at the bottom end of 40, and a limiting assembly for limiting the position of the chuck 37 is arranged on the support cylinder 19; when in use, the simulated picked fruit is fixed on the fixing assembly, the slide 9 is driven by the driving assembly to move so that the fruit is located on the inner side of the clamping assembly, and then the fruit is clamped by the clamping assembly, and then the clamping assembly is driven by the slide 9 to move downward, and the clamping assembly moves downward, and the clamped fruit is driven downward by the connecting column 40 when the fruit moves downward, so as to move the limiting plate 38 downward. A spring 39 is compressed, so that the pulling force of the connecting column 40 on the fruit gradually increases. When the pulling force reaches the pulling force of the fruit stem when picking the fruit, the limit assembly releases the limit on the chuck 37, allowing the chuck 37 to move downward. Finally, with the movement of the clamping assembly, the limit plate 38 and the chuck 37 are both moved out from the inside of the support tube 19, thereby accurately simulating the process of pulling off the fruit stem when picking the fruit. During the detection process, photos are taken by a high-speed camera and processed by a computer 3 to observe the slippage of the clamping contact surface during the clamping process.

[0033] The specific detection methods are as follows:

[0034] 1. Test preparation stage

[0035] 1.1 Sample installation and parameter calibration

[0036] The simulated picked fruit (sample) is mounted on the bottom end of the connecting column 40 through the fixing assembly, and the axis of the sample and the clamping assembly are ensured to be aligned;

[0037] The elastic coefficient of the first spring 39 is calibrated, and the tension threshold F_th is preset according to the fruit stem breaking strength (calculated by the formula F_th = k×Δx_max, k is the spring stiffness coefficient, Δx_max is the preset maximum compression deformation);

[0038] Adjust the trigger threshold of the limit assembly to match F_th to ensure that the chuck 37 limit is released when the pulling force reaches the threshold;

[0039] Set the shooting parameters of the high-speed camera 2 (frame rate ≥ 1000 fps, resolution ≥ 1920 × 1080), and calibrate the slip detection accuracy of the image processing system of computer 3 (≤ 0.02 mm).

[0040] 2. Dynamic loading and data collection stage

[0041] 2.1 Clamping and positioning

[0042] Start the driving assembly to control the slide 9 to move vertically so that the clamping assembly is positioned to the outer surface of the sample;

[0043] Activate the clamping assembly to apply a preload force F_p (F_p<0.2F_th) to the sample and record the initial contact surface position data;

[0044] The computer 3 establishes a three-dimensional coordinate system for the sample and marks the reference points of the clamping contact area.

[0045] 2.2 Dynamic loading simulation

[0046] The slide 9 is driven to move downward at a constant speed v (adjustable from 0.5 to 5 mm / s), driving the clamping assembly to stretch the sample;

[0047] Monitor the displacement Δx of the connecting column 40 in real time, calculate the current tension value F=k×Δx, and simultaneously collect the following data:

[0048] a) High-speed camera 2 captures the slip vector of the clamping contact surface (including the slip distance d and direction angle θ);

[0049] b) Dynamic load curve F(t) corresponding to the spring compression Δx;

[0050] c) The correspondence between the displacement h of the slide 9 and the time t.

[0051] 2.3 Fruit stalk fracture simulation

[0052] When F(t) reaches a preset threshold value F_th, the limit assembly releases the constraint of the chuck 37;

[0053] The chuck 37 and the connecting column 40 move downward at an accelerated speed under the action of the spring rebound force, simulating the impact process of the fruit stem breaking at the moment (acceleration a>3g);

[0054] High-speed camera 2 captures the transient slip characteristics of the contact surface at the moment of fracture, and simultaneously records the sudden drop time Δt (accuracy 0.1 ms) of the tensile force value from F_th to F=0.

[0055] 3. Data analysis and performance evaluation stage

[0056] 3.1 Data fusion processing

[0057] The slip trajectory data is aligned with the load curve in time synchronization to generate a three-dimensional correlation data set of "force-displacement-slip amount";

[0058] Extract key feature parameters:

[0059] a) Maximum slip d_max and its corresponding critical tension F_c;

[0060] b) The change gradient of slip rate v_s=dd / dt before and after fracture;

[0061] c) Dynamic change curve of friction coefficient μ=F(t) / N in the impact stage (N is the clamping normal force).

[0062] 3.2 Quantitative evaluation of anti-slip performance

[0063] Calculate the slip energy integral E_s=∫F(t)×d(t)dt to characterize the accumulated slip work during the clamping process;

[0064] Evaluation of dynamic impact retention η = (1-d_post / d_pre) × 100%, where d_pre is the slip before fracture and d_post is the residual slip after impact;

[0065] Construct anti-slip failure criterion: when η<85% and E_s>preset threshold, it is judged that the impact slip resistance of the flexible contact material does not meet the standard.

[0066] 4. Test termination and reset

[0067] After the test is completed, the drive assembly resets the slide 9 to the initial position;

[0068] Manually reset the chuck 37 and the limit assembly to prepare for the next cycle test;

[0069] The computer 3 automatically generates a test report, including a slip thermodynamic diagram, a load-slip phase diagram, and a key parameter comparison table.

[0070] This solution accurately reproduces the dynamic load characteristics of the fruit stem when it is detached through the synergistic effect of the spring elastic system and the limit component. The compression process of the first spring 39 can linearly simulate the biomechanical response of the fruit stem when it is stretched. When the tension reaches the preset threshold (fruit stem breaking strength), the instantaneous release mechanism of the limit component accurately restores the dynamic impact process of the fruit stem breaking, making the detection environment highly consistent with the mechanical characteristics of the actual picking scene. On the basis of retaining the 2D and 3D displacement detection of the high-speed camera, the dynamic collection of the mechanical parameters of the fruit stem fracture is added. Through the correlation calculation of the spring deformation and the tension value, the dynamic load curve (including key parameters such as the maximum tension and impact rate) in the clamping process can be synchronously obtained. Combined with the slip vector The "mechanics-displacement" two-dimensional evaluation system is constructed based on quantitative data, which significantly improves the comprehensiveness of the performance evaluation of the anti-slip gasket; by simulating the load mutation at the moment of fruit stalk fracture, the anti-slip retention ability of the flexible anti-slip gasket 12 under dynamic impact is effectively verified. Compared with the static clamping test, this scheme can more realistically reflect the degradation law of the material's anti-slip performance under extreme conditions of orchard picking; at the moment of fruit stalk fracture, the high-speed camera 2 can synchronously capture the micro-slip of the contact surface between the clamp and the fruit (with a resolution of 0.02mm), and combined with the time series data of the sudden drop in spring force value, the key failure characteristics of the flexible material under dynamic load, such as the sudden change in friction coefficient and the hysteresis of deformation recovery, can be quantitatively analyzed, providing a direct experimental basis for material modification.

[0071] In this embodiment, preferably, the driving assembly includes a mounting frame 6, a motor 7 fixedly mounted on the mounting frame 6 and a driving screw 5 rotatably mounted on the stand 4, the mounting frame 6 is fixedly mounted on the top of the front side of the stand 4, the output end of the motor 7 is fixedly connected to the top of the driving screw 5, the driving screw 5 passes through the slide 9, and the driving screw 5 is threadedly connected to the slide 9; the driving screw 5 can be driven to rotate by the motor 7, and when the driving screw 5 rotates, the slide 9 can be driven to rise and fall.

[0072] In this embodiment, preferably, the clamping assembly includes a guide rail 10 and two clamping plates 11 slidably mounted on the guide rail 10. A flexible anti-skid pad 12 is detachably mounted on one side of the two clamping plates 11 close to each other. The flexible anti-skid pad 12 is made of a transparent material so that the high-speed camera 2 can capture the deformation of the flexible anti-skid pad 12. A slip sensor is arranged inside the flexible anti-skid pad 12. The slip sensor determines the appropriate gripping force value by detecting the slippage between the robot and the grasped object in real time, so that the robot gradually increases the force without damaging the object, thereby achieving stable grasping of objects with different shapes and surface characteristics, such as grasping fragile objects or objects with high surface accuracy requirements. When the robot is operating the parts, the sliding sensor can ensure that the robot operates with appropriate force; two first racks 14 are slidably arranged on the guide rail 10, and the ends of the two first racks 14 are fixedly connected to the two slide seats 9 respectively; a first gear 13 is rotatably arranged in the middle of the guide rail 10, and the two first racks 14 are meshed with the first gear 13; a driving element 15 is installed on the slide seat 9, and the driving element 15 is transmission-connected with the first gear 13. The first gear 13 can be driven to rotate by the driving element 15, thereby driving the two first racks 14 to move synchronously in the opposite direction, thereby driving the two clamping plates 11 to move synchronously in the opposite direction, so as to clamp the fruit through the two flexible anti-slip pads 12.

[0073] In this embodiment, preferably, a connecting plate 16 is fixedly installed on one side of the mounting frame 6, a connecting frame 17 is fixedly mounted on the supporting tube 19, and the connecting frame 17 is connected to the connecting plate 16 through a tension sensor 18; after the fruit is fixed on the fixed component, the value of the tension sensor 18 is reset to zero, and when the subsequent clamping component pulls the fruit downward, the value of the tension sensor 18 is the simulated tension value of the fruit stem on the fruit.

[0074] See also Figure 3 to Figure 5In the embodiment of the present invention, the limiting assembly includes a support plate 20, which is fixedly mounted on the support tube 19. A second slide groove 2002 is provided at the bottom of the inner side of the support plate 20. A stopper 21 for limiting the chuck 37 is provided inside the second slide groove 2002 for sliding. An inclined surface is provided at the bottom of the stopper 21 to facilitate the chuck 37 to extend into the support tube 19. A first slide groove 2001 is provided on the support plate 20. A slider 23 is longitudinally slidably installed inside the first slide groove 2001. An adjusting screw 25 is rotatably installed at the top end of the slider 23. The adjusting screw 25 passes through the top wall of the support plate 20, and the adjusting screw 25 is threadedly connected to the support plate 20. The adjusting screw 2 5 is fixedly installed with a knob at the top, and a driving block 24 is installed in the slider 23 for horizontal sliding. One end of the driving block 24 extends into the inner side of the support tube 19, and the top of the end of the driving block 24 extending into the support tube 19 is provided with an inclined surface. When the limit plate 38 moves downward to contact with the inclined surface on the driving block 24, as the limit plate 38 continues to move downward, the limit plate 38 pushes the driving block 24 to move in a direction away from the limit plate 38. A transmission rod 26 is provided on one side of the support plate 20, and a fourth slide groove 2601 is provided on the transmission rod 26. One end of the driving block 24 extends into the fourth slide groove 2601, and the driving block 24 slides up and down with the fourth slide groove 2601, so that the driving block 24 When the fruit moves horizontally, it can drive the transmission rod 26 to move synchronously. When the driving block 24 moves up and down, it cannot drive the transmission rod 26 to move. A first slide post 22 is fixedly connected to one side of the stopper 21, and one end of the first slide post 22 is fixedly connected to the transmission rod 26. A third slide groove 2003 is provided on the support plate 20, and a second slide post 27 is slidably arranged in the third slide groove 2003. One end of the second slide post 27 is fixedly connected to the transmission rod 26, and the other end of the second slide post 27 is elastically connected to the inner side wall of the third slide groove 2003 through a second spring 28, and the second spring 28 is in a stretched state. When the clamping assembly clamps the fruit and moves downward, the connecting column 40 pulls the limit plate 38 to move downward. After the moving block 24 contacts, as the limit plate 38 continues to move downward, the limit plate 38 pushes the driving block 24 to move in the direction away from the limit plate 38, thereby driving the transmission rod 26 to move in the direction away from the support tube 19. When the transmission rod 26 moves, it drives the block 21 to move through the first slide column 22, so that the block 21 releases the limit on the chuck 37, so that the chuck 37 and the limit plate 38 can move out of the support tube 19, thereby simulating the process of picking fruits from the fruit tree. Under the pulling force of the second spring 28, the transmission rod 26 can drive the block 21 and the driving block 24 to reset. It should be noted that the diameter of the limit plate 38 is smaller than the diameter of the chuck 37, so that the limit plate 38 will not contact the block 21 when it moves downward;The height of the slider 23 can be adjusted by rotating the adjusting screw 25. The lower the height of the slider 23 is, the greater the compression degree of the first spring 39 is when the block 21 releases the lock on the chuck 37. At this time, the pulling force value of the fruit stem when simulating fruit picking is greater, thereby achieving the adjustment of the pulling force value of the fruit stem to simulate the picking of different fruits. ;

[0075] See also Figure 3 and Figure 7 to Figure 9 In the embodiment of the present invention, the fixing assembly includes an installation box 29, and the installation box 29 is fixedly installed at the bottom end of the connecting column 40. A winding roller 30 is rotatably installed in the installation box 29, and an elastic fixing belt 31 is wound around the winding roller 30. The end of the elastic fixing belt 31 is fixedly connected to a connecting seat 32. The connecting seat 32 is located on one side of the installation box 29, and a slot 2901 is opened on the other side of the installation box 29. A card block 3201 is arranged on the connecting seat 32. When the connecting seat 32 is inserted into the slot 2901, the connecting seat 32 passes through the card block 3201. The mounting box 29 is engaged with the slot 2901 and can be released by a button on the mounting box 29; a mounting tube 35 is fixedly mounted on one end of the mounting box 29, one end of the winding roller 30 extends into the mounting tube 35, a spring 36 is arranged in the mounting tube 35, one end of the spring 36 is fixedly connected to the winding roller 30, and the other end of the spring 36 is fixedly connected to the inner wall of the mounting tube 35, the end of the winding roller 30 away from the mounting tube 35 passes through the side wall of the mounting box 29, and the end of the winding roller 30 away from the mounting tube 35 is fixedly sleeved with a second gear 34, and one end of the connecting seat 32 A second rack 33 is fixedly installed at the end, and the second rack 33 is adapted to the second gear 34. When the connecting seat 32 is inserted into the slot 2901, the second rack 33 meshes with the second gear 34 and drives the second gear 34 to rotate, so that the winding roller 30 rotates in the direction of tightening the elastic fixing belt 31; when fixing the fruit, the elastic fixing belt 31 is pulled out from the winding roller 30 through the connecting seat 32, and after the elastic fixing belt 31 is passed around the fruit, the connecting seat 32 is inserted into the slot 2901, so that the connecting seat 32 is engaged and connected with the slot 2901 through the clamping block 3201 When the connecting seat 32 is inserted into the slot 2901, the second rack 33 meshes with the second gear 34 and drives the second gear 34 to rotate, so that the winding roller 30 rotates in the direction of tightening the elastic fixing belt 31, so that the elastic fixing belt 31 wrapped around the fruit is tightened, thereby improving the firmness of the fruit fixation. When releasing the fixation of the fruit, press the button on the installation box 29 to release the engagement connection between the card block 3201 and the slot 2901. After taking out the fruit, under the action of the spring 36, the winding roller 30 rotates in the opposite direction so that the elastic fixing belt 31 is rewound back onto the winding roller 30.

[0076] The present invention also discloses a detection method of a flexible contact slip detection device, comprising the following steps:

[0077] S1. Fix the simulated picked fruit on the fixed assembly, drive the slide 9 to move the fruit through the drive assembly so that the fruit is located inside the clamping assembly, and then clamp the fruit through the clamping assembly;

[0078] S2. The clamping assembly is driven to move downward by the slide 9. When the clamping assembly moves downward, the clamped fruit is driven to move downward. When the fruit moves downward, the limit plate 38 is driven to move downward by the connecting column 40, thereby compressing the first spring 39, so that the pulling force of the connecting column 40 on the fruit gradually increases. When the pulling force reaches the pulling force of the fruit stem when picking the fruit, the limit assembly releases the limit on the chuck 37, so that the chuck 37 can move downward. Finally, with the movement of the clamping assembly, the limit plate 38 and the chuck 37 are both moved out from the inside of the support tube 19, thereby accurately simulating the process of pulling off the fruit stem when picking the fruit;

[0079] S3. During the detection process, photos are taken by a high-speed camera, and the taken photos are processed by computer 3 to observe the slippage of the clamping contact surface during the clamping process.

[0080] The above description is only a preferred embodiment of the present invention, so all equivalent changes or modifications made according to the structure, characteristics and principles described in the scope of the patent application of the present invention are included in the scope of the patent application of the present invention.

Claims

1. A flexible contact slip detection device, comprising a detection platform (1), a computer (3) arranged on the detection platform (1), a high-speed camera (2) arranged on one side of the detection platform (1), and a detection mechanism arranged on the detection platform (1), characterized in that: The detection mechanism comprises a stand (4), a slide seat (9) is slidably mounted on the stand (4), a driving assembly for driving the slide seat (9) to rise and fall is arranged on the stand (4), a clamping assembly for clamping a sample is arranged on the slide seat (9), a support tube (19) is arranged on one side of the stand (4), the support tube (19) is arranged just above the clamping assembly, and a chuck (37), a connecting column (40) and a limit plate ( 38), the connecting column (40) passes through the chuck (37), and the connecting column (40) and the chuck (37) are slidably matched, the limiting plate (38) is fixedly connected to the top of the connecting column (40), the limiting plate (38) and the chuck (37) are elastically connected through a first spring (39), the bottom end of the connecting column (40) is equipped with a fixing component for fixing the sample, and the supporting cylinder (19) is provided with a limiting component for limiting the chuck (37); The limiting assembly comprises a support plate (20), wherein the support plate (20) is fixedly mounted on the support tube (19), a second slide groove (2002) is provided at the bottom of the inner side of the support plate (20), a stopper (21) for limiting the chuck (37) is slidably arranged inside the second slide groove (2002), a first slide groove (2001) is provided on the support plate (20), a slider (23) is longitudinally slidably arranged inside the first slide groove (2001), an adjusting screw (25) is rotatably mounted at the top end of the slider (23), and the adjusting screw (25) passes through the support plate (20). The top wall is provided with a screw rod (25) and a screw threaded connection with the support plate (20). A driving block (24) is installed in the interior of the slider (23) for horizontal sliding. One end of the driving block (24) extends into the inner side of the support tube (19), and an inclined surface is provided on the top of the end of the driving block (24) extending into the support tube (19). A transmission rod (26) is provided on one side of the support plate (20), and a fourth sliding groove (2601) is provided on the transmission rod (26). One end of the driving block (24) extends into the fourth sliding groove (2601), and the driving block (24) and the fourth sliding groove (2601) are slidably matched up and down.

2. A flexible contact slip detection device according to claim 1, characterized in that: The driving assembly comprises a mounting frame (6), a motor (7) fixedly mounted on the mounting frame (6), and a driving screw (5) rotatably mounted on the stand (4); the mounting frame (6) is fixedly mounted on the top of the front face of the stand (4); the output end of the motor (7) is fixedly connected to the top end of the driving screw (5); the driving screw (5) passes through the slide seat (9), and the driving screw (5) is threadedly connected to the slide seat (9).

3. A flexible contact slip detection device according to claim 1, characterized in that: A first sliding column (22) is fixedly connected to one side of the stopper (21), one end of the first sliding column (22) is fixedly connected to the transmission rod (26), a third sliding groove (2003) is provided on the support plate (20), a second sliding column (27) is slidably arranged in the third sliding groove (2003), one end of the second sliding column (27) is fixedly connected to the transmission rod (26), and the other end of the second sliding column (27) is elastically connected to the inner wall of the third sliding groove (2003) through a second spring (28).

4. The flexible contact slip detection device according to claim 1, characterized in that: The fixing assembly comprises a mounting box (29), wherein the mounting box (29) is fixedly mounted on the bottom end of the connecting column (40), a winding roller (30) is rotatably mounted in the mounting box (29), an elastic fixing belt (31) is wound around the winding roller (30), an end of the elastic fixing belt (31) is fixedly connected to a connecting seat (32), the connecting seat (32) is located on one side of the mounting box (29), a slot (2901) is provided on the other side of the mounting box (29), a clamping block (3201) is provided on the connecting seat (32), and when the connecting seat (32) is inserted into the slot (2901), the connecting seat (32) is clamped and connected to the slot (2901) through the clamping block (3201).

5. A flexible contact slip detection device according to claim 4, characterized in that: A mounting tube (35) is fixedly mounted on one end of the mounting box (29), one end of the winding roller (30) extends into the mounting tube (35), a spring (36) is arranged in the mounting tube (35), one end of the spring (36) is fixedly connected to the winding roller (30), the other end of the spring (36) is fixedly connected to the inner wall of the mounting tube (35), one end of the winding roller (30) away from the mounting tube (35) passes through the side wall of the mounting box (29), and the winding roller (30) A second gear (34) is fixedly mounted on one end away from the mounting tube (35), and a second rack (33) is fixedly mounted on one end of the connecting seat (32). The second rack (33) is matched with the second gear (34). When the connecting seat (32) is inserted into the slot (2901), the second rack (33) meshes with the second gear (34) and drives the second gear (34) to rotate, so that the winding roller (30) rotates in the direction of tightening the elastic fixing belt (31).

6. A flexible contact slip detection device according to claim 2, characterized in that: A connecting plate (16) is fixedly mounted on one side of the mounting frame (6), a connecting frame (17) is fixedly mounted on the supporting cylinder (19), and the connecting frame (17) is connected to the connecting plate (16) via a tension sensor (18).

7. The flexible contact slip detection device according to claim 1, characterized in that: The clamping assembly comprises a guide rail (10) and two clamping plates (11) slidably mounted on the guide rail (10); a flexible anti-skid pad (12) is detachably mounted on one side of the two clamping plates (11) close to each other; and a slip sensor is arranged inside the flexible anti-skid pad (12).

8. A flexible contact slip detection device according to claim 7, characterized in that: Two first racks (14) are slidably arranged on the guide rail (10), and the ends of the two first racks (14) are fixedly connected to the two slide seats (9) respectively. A first gear (13) is rotatably arranged in the middle of the guide rail (10), and the two first racks (14) are meshed with the first gear (13). A driving element (15) is installed on the slide seat (9), and the driving element (15) is transmission-connected to the first gear (13).

9. A flexible contact slip detection method, using a flexible contact slip detection device according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1. The simulated picked fruit is fixed on the fixed component, the slide (9) is driven by the drive component to move so that the fruit is located inside the clamping component, and then the fruit is clamped by the clamping component; S2. The clamping assembly is driven to move downward by the slide seat (9), and the clamping assembly drives the clamped fruit to move downward when the clamping assembly moves downward. When the fruit moves downward, the limit plate (38) is driven to move downward through the connecting column (40), thereby compressing the first spring (39), so that the pulling force of the connecting column (40) on the fruit gradually increases. When the pulling force reaches the pulling force of the fruit stem when the fruit is picked, the limit assembly releases the limit on the chuck (37), so that the chuck (37) can move downward. Finally, as the clamping assembly moves, the limit plate (38) and the chuck (37) are both moved out from the inside of the support tube (19), thereby accurately simulating the process of pulling off the fruit stem when the fruit is picked; S3. During the detection process, photos are taken by a high-speed camera and processed by a computer (3) to observe the slippage of the clamping contact surface during the clamping process.

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