Metering calibration device and method of tactile sensor

Abstract

The invention provides a metering calibration device and method for a touch sensor. The device comprises a bearing platform, a gantry frame, a pressure loading mechanism, a piston, an oil cylinder and a weight loading mechanism, the pressure loading mechanism comprises an oil storage tank with an oil storage cavity, an opening is formed in the lower end of the oil storage tank and sealed through a flexible film, and the gantry frame is connected with a first lifting mechanism. An inner cavity of the oil cylinder is communicated with the oil storage cavity through an oil pipe, and the weight loading mechanism loads a standard load on the piston so as to pressurize hydraulic oil in the oil storage cavity to form standard pressure. The flexible thin film is adopted as a component in contact with a calibrated tactile sensor array, the pressure transmission characteristic of hydraulic oil is utilized, after the hydraulic oil in an oil storage cavity is pressurized, standard pressure is formed, the flexible thin film deforms downwards and uniformly as a whole, the standard pressure is applied to the calibrated tactile sensor, and the calibrated tactile sensor array is calibrated. Therefore, comprehensive and synchronous metering calibration of all sensing units of the tactile sensor array is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of tactile sensor calibration, and in particular to a metrological calibration device and method for a tactile sensor. Background Art

[0002] Tactile sensors are used in robots to mimic the sense of touch. They are the core component for enabling dexterous hands to sense touch. They can be categorized by function as contact sensors, force-torque sensors, pressure sensors, and slip sensors.

[0003] Most tactile sensors, such as piezoresistive, piezoelectric, capacitive, and electromagnetic, can only sense normal force, and the primary method for acquiring pressure information is by integrating multiple sensing units into a tactile sensor array. Furthermore, tactile sensors are constantly evolving, pursuing higher sensitivity, higher integration, greater scalability, and lower cost.

[0004] In order to ensure the accuracy of the tactile sensor, it is necessary to implement metrological calibration on the tactile sensor. Existing sensor metrological calibration devices, such as the multi-dimensional force loading and calibration device for tactile sensors disclosed in Chinese Patent Application No. 201410272708.2, include a positioning platform, a force loading unit and a vernier caliper; the vernier caliper includes a horizontal vernier caliper and a vertical vernier caliper. The force loading unit includes a stepper motor, a tension and pressure sensor, a rigid kit, a loading force contact, a support platform and a support support. The force loading device is directly mounted on the arc-shaped positioning frame of the positioning platform through the support support and can rotate. By rotating the support support, the rotation of the force loading device is achieved, so that the force loading contact of the force loading device can apply force at different angles to the sample on the slide.

[0005] In the above patent, the force loading device can only load and calibrate a portion of the tactile sensor array, and cannot achieve full loading and full calibration of the entire sensor array.

[0006] The prior art also offers a sensor metrology and calibration device capable of simulating the operating environment of tactile sensors, such as the underwater tactile force sensor array calibration system that provides a temperature and pressure environment disclosed in Chinese Patent Application No. 201710428402.5. The system includes a pressure loading system, a temperature loading system, a tactile force sensor calibration system, and an industrial computer. A sealed simulated pressure tank provides a temperature- and pressure-loaded water environment. The pressure loading system uses a servo motor to drive a pressure plug to pressurize the water in the sealed pressure tank, creating different pressure environments for the underwater tactile force sensors. The temperature loading system consists of a water circulation and water temperature regulation device, enabling the underwater tactile force sensor to be set to different temperature values. The tactile force sensor calibration equipment, placed within the pressure tank, includes a tactile force sensor array fixing device and a force generating device, enabling force sensor array calibration.

[0007] In the above patent, the pressure loading system pressurizes the water to simulate the deep-water environment in which underwater tactile sensors are used. However, the tactile force sensor calibration equipment still needs to contact the tactile array sensors one by one to implement the force calibration experiment, and it is impossible to achieve full loading and full calibration of the entire sensor array.

[0008] In summary, the current tactile sensor calibration device can only load and calibrate a portion of the tactile sensor array, and cannot achieve comprehensive loading and comprehensive calibration of the entire sensor array. Summary of the Invention

[0009] The technical problem to be solved by the present invention is to provide a tactile sensor measurement calibration device and method, which can calibrate the entire tactile sensor array simultaneously.

[0010] The present invention is achieved in that: In a first aspect, the present invention provides a metrological calibration device for a tactile sensor, comprising: a carrying platform for fixing the tactile sensor to be calibrated, a gantry frame, a pressure loading mechanism, a piston, a cylinder, and a weight loading mechanism; The pressure loading mechanism includes an oil storage tank, an oil storage chamber is formed inside the oil storage tank, an opening is provided at the lower end of the oil storage tank, and the opening is sealed by a flexible film. The gantry frame is fixed to the top of the carrying platform, and the gantry frame is connected to a first lifting mechanism for driving the pressure loading mechanism to rise and fall. The first lifting mechanism is used to adjust the distance between the carrying platform and the flexible film to be equal to the thickness of the tactile sensor to be calibrated; The inner cavity of the oil cylinder is connected to the oil storage cavity through an oil pipe, and the piston is slidably connected to the oil cylinder. The standard load of the weight loading mechanism is loaded on the piston to pressurize the hydraulic oil in the oil storage cavity to form a standard pressure, causing the flexible film to deform downward, and the standard pressure is applied to the tactile sensor to be calibrated.

[0011] Furthermore, the first lifting mechanism includes a ball screw and a screw nut spirally connected to the ball screw, the outer wall of the oil storage tank is rigidly provided with a flange, the screw nut is fixedly connected to the flange, the upper and lower ends of the ball screw are respectively rotatably connected to the gantry frame and the supporting platform, the supporting platform is connected to a first servo motor, and the first servo motor is connected to the ball screw.

[0012] Furthermore, the weight loading mechanism includes a loading frame, a suspension rod, several weights and a second lifting mechanism. A pressure head is provided on the inner side of the loading frame, and the pressure head is located above the piston. During loading, the pressure head contacts the piston. The suspension rod is rigidly connected to the bottom of the loading frame. The second lifting mechanism is located at the bottom of the suspension rod and is used to lift the suspension rod. Several weights are mounted on the suspension rod, and the weight loading mechanism also includes a loading assembly for hanging several weights on the suspension rod step by step.

[0013] Furthermore, the loading assembly includes a support platform, the support platform is rotatably connected to a plurality of support columns, and a ring array of the plurality of support columns is arranged on the outside of the boom with the boom axis as the center; According to the number of the weights, each support column is provided with through holes spaced evenly from top to bottom, and the through holes are arranged in a spiral along the axis of the support column, and support rods for supporting the weights are inserted into the through holes; Each of the support columns is connected to a first sprocket, and the first sprockets are commonly connected to a chain. A second servo motor is also provided on the support platform, and the second servo motor is connected to a second sprocket, and the second sprocket is connected to the chain.

[0014] Furthermore, the bottom of the pressure head is a spherical surface.

[0015] Furthermore, it also includes an oil pressure meter, the oil pressure meter has five detection sensing ends, one of which is used to detect the hydraulic oil pressure in the oil cylinder cavity; The remaining detection sensing ends are evenly arranged at the lower end of the oil storage tank near the flexible film, and are used to detect whether the hydraulic oil pressure in the oil storage chamber is consistent with the hydraulic oil pressure in the oil cylinder cavity, and are also used to determine whether the pressure on the flexible film is uniform.

[0016] Furthermore, a laser interferometer is included, which is connected to the carrying platform and is used to measure the distance between the carrying platform and the flexible film.

[0017] Furthermore, the middle section of the oil pipe is connected to an oil reservoir In a second aspect, the present invention provides a metrological calibration method for a tactile sensor, based on the metrological calibration device for a tactile sensor described in the first aspect, the calibration method comprising the following steps: S1. Measuring the thickness of the tactile sensor to be calibrated, and controlling the first lifting mechanism to move according to the thickness of the tactile sensor to be calibrated until the distance between the supporting platform and the flexible film is equal to the thickness of the tactile sensor to be calibrated; S2. The weight loading mechanism applies a load to the piston, and the detection sensing end detects the hydraulic oil pressure in the cylinder cavity and the oil storage cavity respectively; when the pressure in the cylinder cavity and the oil storage cavity are equal, and the pressure on the flexible film is uniform, the computer collects the output of the current calibrated tactile sensor and compares it with the standard pressure in the oil storage cavity corresponding to the standard load applied by the weight loading mechanism to achieve calibration of the calibrated tactile sensor.

[0018] Furthermore, in step S2, the load point to be calibrated is determined according to the measuring range of the tactile sensor to be calibrated, and the weight loading mechanism applies a standard load on the piston step by step, and each time a standard load is applied, the corresponding standard pressure point of the tactile sensor to be calibrated is calibrated.

[0019] The advantages of this invention lie in its use of a flexible film as the contact component with the tactile sensor array being calibrated. By leveraging the pressure-transmitting properties of hydraulic oil, the flexible film deforms uniformly downward as a whole when the hydraulic oil in the reservoir is pressurized, thereby comprehensively and synchronously loading all sensing units in the tactile sensor array being calibrated. This solves the problem of prior art, which only allows loading calibration of a localized area of ​​the tactile sensor array, and improves the integrity and comprehensiveness of the calibration.

[0020] A precisely controllable standard load is applied to the piston step by step through the weight loading mechanism, and the standard pressure is stably transmitted to the flexible film through hydraulic transmission. This can achieve accurate pressure loading from small to large on the tactile sensor to be calibrated within the measuring range, thereby realizing wide-range, high-precision calibration and ensuring accurate and reliable tactile sensing measurements. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0022] Figure 1 The figure is a schematic structural diagram of a measurement and calibration device for a tactile sensor in the present invention.

[0023] Figure 2 It is a schematic diagram of the connection structure of the carrying platform, gantry frame, pressure loading mechanism and laser interferometer in the present invention.

[0024] Figure 3 for Figure 2 A partial enlarged view of point A in the middle.

[0025] Figure 4 for Figure 2 A partial enlarged view of point B in the middle.

[0026] Figure 5 Schematic diagram of the weight loading mechanism structure in the present invention.

[0027] Figure 6This is a structural diagram of the four high-precision oil pressure sensors of the present invention arranged in the oil storage tank.

[0028] Figure 7 Schematic diagram of the connection structure between the weight and the suspension rod in the present invention.

[0029] Figure 8 This is a schematic diagram of the loading component structure in the present invention.

[0030] Figure 9 This is a schematic diagram of the connection structure of the first sprocket, the second sprocket and the chain in the present invention.

[0031] Figure 10 It is a schematic diagram of the connection structure between the support column and the support rod in the present invention.

[0032] Figure 11 This is a schematic diagram of the connection structure between the computer, the first driver, the second driver, the second lifting mechanism, the laser interferometer and the oil pressure meter in the present invention.

[0033] Description of the numbers in the figure: 1. Tactile sensor to be calibrated; 2. Carrying platform; 3. Gantry frame; 4. Pressure loading mechanism; 41. Oil storage tank; 411. Oil storage chamber; 42. Flexible film; 43. Flange; 5. Piston; 6. Oil cylinder; 7. Weight loading mechanism; 71. Loading frame; 72. Hanging rod; 721. Retaining ring; 73. Weight; 74. Second lifting mechanism; 75. Pressure head; 76. Loading assembly; 761. Support platform; 762. Support column; 763. Support rod; 764. First sprocket; 765. Chain; 766. Second servo motor; 767. Second sprocket; 8. First lifting mechanism; 81. Ball screw; 82. Screw nut; 83. First servo motor; 9. Oil pipe; 10. Oil pressure gauge; 101. High-precision oil pressure sensor; 11. Laser interferometer; 111. Laser light source; 112. Fiber optic coupler; 113. Measuring arm; 114. Reference arm; 115. Spectrometer; 12. Oil reservoir. DETAILED DESCRIPTION

[0034] For example 1, please refer to Figures 1 to 11 The present invention provides a metrological calibration device for a tactile sensor, comprising: a carrying platform 2 for fixing a tactile sensor 1 to be calibrated, a gantry frame 3, a pressure loading mechanism 4, a piston 5, an oil cylinder 6, and a weight loading mechanism 7; The pressure-loading mechanism 4 includes an oil tank 41, which defines an oil storage chamber 411 within it. The lower end of the oil tank 41 has an opening sealed by a flexible film 42 made of a flexible material, such as silicone rubber. The film 42 is 1 mm thick. The oil tank 41 is a thick-walled steel cylinder, meaning its top and side walls are made of thick steel plates. When the weight-loading mechanism 7 applies a standard load, the top and side walls of the oil tank 41 remain unchanged, and the oil storage chamber 411 is filled with hydraulic oil. The gantry frame 3 is fixed on the top of the carrying platform 2. The gantry frame 3 is connected to a first lifting mechanism 8 for driving the pressure loading mechanism 4 to move up and down. The first lifting mechanism 8 is used to adjust the distance between the carrying platform 2 and the flexible film 42 to be equal to the thickness of the tactile sensor 1 to be calibrated. The inner cavity of the oil cylinder 6 is connected to the oil storage chamber 411 through the oil pipe 9, and the piston 5 is slidably connected to the oil cylinder 6. The standard load of the weight loading mechanism 7 is loaded on the piston 5 to pressurize the hydraulic oil in the oil storage chamber 411 to form a standard pressure, causing the flexible film 42 to deform downward. The standard pressure is applied to the tactile sensor 1 to be calibrated to achieve calibration of the tactile sensor 1 to be calibrated.

[0035] Specifically, the first lifting mechanism 8 includes a ball screw 81 and a screw nut 82 screwedly connected to the ball screw 81. The outer wall of the oil storage tank 41 is rigidly provided with a flange 43, and the screw nut 82 is fixedly connected to the flange 43. The upper and lower ends of the ball screw 81 are respectively rotatably connected to the gantry frame 3 and the supporting platform 2. The supporting platform 2 is connected to a first servo motor 83, which is connected to the ball screw 81. The first servo motor 83 is connected to a first driver, which is connected to a computer.

[0036] Specifically, the weight loading mechanism 7 includes a loading frame 71, a suspension rod 72, several weights 73, and a second lifting mechanism 74. The second lifting mechanism 74 is a screw lift. A pressure head 75 is provided on the inner side of the loading frame 71. The pressure head 75 is located above the piston 5. During loading, the pressure head 75 contacts the piston 5. The suspension rod 72 is rigidly connected to the bottom of the loading frame 71. The second lifting mechanism 74 is located at the bottom of the suspension rod 72 and is used to lift the suspension rod 72. Before loading, the second lifting mechanism 74 rises to separate the pressure head 75 from the piston 5. During loading, the second lifting mechanism 74 descends, so that the standard load of the weight loading mechanism 7 is applied to the pressure head 75.

[0037] A through hole is provided at the center of each weight 73, and several of the weights 73 are mounted on the suspension rod 72, which is passed through the through hole. The weight loading mechanism 7 also includes a loading assembly 76 for hanging several weights 73 on the suspension rod 72 step by step. A retaining ring 721 is provided on the outer wall of the suspension rod 72 to prevent the weights 73 from slipping. During loading, the lowest weight 73 contacts the retaining ring 721, and the weights 73 are loaded step by step to realize standard pressure loading of the calibrated tactile sensor 1 from small to large within the measuring range.

[0038] Specifically, the loading assembly 76 includes a support platform 761, and the second lifting mechanism 74 is installed on the support platform 761. The support platform 761 is rotatably connected to a plurality of support columns 762. With the axis of the boom 72 as the center, a circular array of the support columns 762 is arranged on the outside of the boom 72; three support columns 762 are provided.

[0039] According to the number of the weights 73, each support column 762 is provided with mounting holes spaced evenly from top to bottom, and the mounting holes are arranged in a spiral along the axis of the support column 762. A support rod 763 for supporting the weights 73 is inserted into the mounting hole; Each support column 762 is connected to a first sprocket 764, which is collectively connected to a chain 765. A second servo motor 766 is also provided on the support platform 761. The second servo motor 766 is connected to a second sprocket 767, which is in turn connected to the chain 765. The second servo motor 766 is connected to a second driver, which is connected to a computer. When the second servo motor 766 rotates, the three support columns 762 rotate synchronously via a sprocket and chain transmission.

[0040] If the number of weights 73 is set to 9, the number of support rods 763 is also 9, each support rod 763 corresponds to a weight 73, and from bottom to top, the angle between the axes of two adjacent support rods 763 is Support column 762 is also connected to an encoder for identifying the rotation angle of support column 762, which is connected to a computer. Initially, the lowest support rod 763 contacts the lowest weight 73, supporting all weights 73 above it. At this point, only the standard loads of loading frame 71, suspension rod 72, and indenter 75 are applied to piston 5, achieving the first level of loading.

[0041] When loading the second-level standard load, the second lifting mechanism 74 rises, raising the loading frame 71 and the suspension rod 72. Subsequently, the support column 762 rotates 36 degrees. At this point, the lowest weight 73 separates from the lowest support rod 763. From the bottom up, the second support rod 763 moves below the second weight 73. After the second lifting mechanism 74 descends to its initial position, the second support rod 763 supports the second through ninth weights 73, allowing the first weight 73 to be attached to the suspension rod 72 via the retaining ring 721, thus achieving loading of the second-level standard load.

[0042] Following the second-level standard load, weights 73 are stacked one by one on the suspension rod 72 to achieve step-by-step loading. After support column 762 rotates nine times (36° each rotation), all support rods 763 are separated from weights 73, allowing all nine weights 73 to be hung on the suspension ring.

[0043] When all nine weights 73 are hung on the hanging rings, after the support column 762 rotates 36° again, the lowest weight 73 contacts the lowest support rod 763, and all nine weights 73 are supported by the lowest support rod 763.

[0044] Specifically, the bottom of the pressure head 75 is a spherical surface. By providing the spherical surface, the standard load applied by the weight loading mechanism 7 is more evenly distributed on the piston 5.

[0045] Specifically, it also includes an oil pressure meter 10, which has five detection sensing ends, each of which is a high-precision oil pressure sensor 101, one of which is used to detect the hydraulic oil pressure in the inner cavity of the oil cylinder 6; The remaining detection sensing terminals are evenly arranged at the lower end of the oil reservoir 41, near the flexible film 42, to detect whether the hydraulic oil pressure within the oil reservoir chamber 411 is consistent with the hydraulic oil pressure within the oil cylinder 6. The outputs of the four detection sensing terminals can be used to determine whether the pressure experienced by the flexible film 42 is uniform. When the hydraulic oil pressure within the oil reservoir chamber 411 is consistent with the hydraulic oil pressure within the oil cylinder 6, and the pressure experienced by the flexible film 42 is uniform, the standard pressure within the oil reservoir chamber corresponding to the standard load applied by the weight loading mechanism 7 becomes the standard pressure experienced by the calibrated tactile sensor 1. This pressure is then compared with the output of the calibrated tactile sensor 1 currently collected by the computer to calibrate the calibrated tactile sensor 1.

[0046] Specifically, a laser interferometer 11 is further included, which is connected to the carrying platform 2 and is used to measure the distance between the carrying platform 2 and the flexible film 42. The laser interferometer 11 is composed of a laser light source 111, a fiber coupler 112, a measuring arm 113, a reference arm 114, and a spectrometer 115. The measuring arm 113 is fixed vertically upward on the carrying platform 2. In addition, the measuring arm 113, the reference arm 114, and the light source are all connected to the fiber coupler 112, the fiber coupler 112 is connected to the spectrometer 115, and the spectrometer 115 is connected to a computer. After the thickness of the tactile sensor is determined and input into the computer, the laser interferometer 11 confirms the distance between the flexible film 42 and the carrying platform 2. The computer controls the first driver to start the first servo motor 83, driving the ball screw 81 to rotate, causing the oil storage tank 41 to move downward. During the movement, the laser interferometer 11 continuously measures the distance between the carrying platform 2 and the flexible film 42 and feeds it back to the computer, forming a closed-loop control until the distance between the carrying platform 2 and the flexible film 42 is equal to the thickness of the tactile sensor.

[0047] Specifically, the middle section of the oil pipe 9 is connected to an oil reservoir 12. During operation, the oil reservoir 12 realizes real-time dynamic adjustment and replenishment of the hydraulic oil.

[0048] For example 2, please refer to Figures 1 to 11 The present invention provides a metrological calibration method for a tactile sensor, based on the metrological calibration device for a tactile sensor described in Example 1, the calibration method comprises the following steps: S1. Measure the thickness of the tactile sensor 1 to be calibrated, and control the first lifting mechanism 8 to move according to the thickness of the tactile sensor 1 to be calibrated until the distance between the supporting platform 2 and the flexible film 42 is equal to the thickness of the tactile sensor 1 to be calibrated; In step S1, the thickness of the tactile sensor is measured using a micrometer and the measurement data is input into a computer. A laser interferometer 11 measures the distance between the flexible film 42 and the supporting platform 2 and feeds the measurement data back to the computer. Based on the tactile sensor thickness and the measurement data from the laser interferometer 11, the computer controls the first servo motor 83 via a first driver to activate and drive the ball screw 81 to rotate, causing the oil tank 41 to move downward. During this movement, the laser interferometer 11 continuously measures the distance between the supporting platform 2 and the flexible film 42 and feeds this back to the computer, forming a closed-loop control loop until the distance between the supporting platform 2 and the flexible film 42 equals the thickness of the tactile sensor. The computer also records the zero points of the four high-precision oil pressure sensors 101 located on the oil tank 41.

[0049] S2, the weight loading mechanism 7 applies a standard load to the piston 5, and the detection sensing end detects the hydraulic oil pressure in the inner cavity of the oil cylinder 6 and the oil storage chamber 411 respectively; when the pressure in the inner cavity of the oil cylinder 6 and the oil storage chamber 411 are equal, and the pressure on the flexible film 42 is uniform, the computer collects the output of the current calibrated tactile sensor 1 and compares it with the standard pressure in the oil storage chamber corresponding to the standard load applied by the weight loading mechanism 7 to achieve calibration of the calibrated tactile sensor 1.

[0050] Specifically, in step S2, the load point that needs to be calibrated is determined according to the measuring range of the tactile sensor 1 to be calibrated, and the weight loading mechanism 7 applies the corresponding standard load on the piston 5 step by step. Each time a standard load is applied, the computer calibrates the corresponding standard pressure point of the tactile sensor to be calibrated.

[0051] Before the weight loading mechanism 7 is loaded, the second lifting mechanism 74 is raised, and the loading frame 71 and the suspension rod 72 are moved upward, so that the pressure head 75 is separated from the piston 5.

[0052] During loading, the second lifting mechanism 74 retracts, the loading frame 71 and the suspension rod 72 move downward, so that the pressure head 75 presses on the piston 5, achieving the first level of loading. The pressure in the oil cylinder is: ; The pressure in the oil storage chamber is: ; Where, is the total weight of the loading frame 71, the suspension rod 72 and the pressing head 75, which is a known parameter and can be measured by a weighing device; is the cross-sectional area of ​​the inner cavity of the oil cylinder 6, which is a known parameter; According to the above formula, the standard pressure in the oil storage cavity corresponding to the standard load applied by the weight loading mechanism 7 can be calculated, which is the standard pressure borne by the calibrated tactile sensor 1 .

[0053] After the weight loading mechanism 7 is loaded, the five high-precision oil pressure sensors 101 respectively collect the hydraulic oil pressure in the inner cavity of the oil cylinder 6 and the oil storage chamber 411, and compare the two to see if they are consistent. Furthermore, based on the outputs of the four high-precision oil pressure sensors 101 connected to the lower portion of the oil storage tank 41, the computer can determine whether the pressure on the flexible film 42 is uniform. When the hydraulic oil pressure in the oil storage chamber 411 is consistent with the hydraulic oil pressure in the inner cavity of the oil cylinder 6, and the pressure on the flexible film 42 is uniform, the standard pressure in the oil storage chamber corresponding to the standard load applied by the weight loading mechanism 7 is the standard pressure on the calibrated tactile sensor 1. This is compared with the output of the calibrated tactile sensor 1 currently collected by the computer, thereby achieving calibration of the calibrated tactile sensor 1 at that load point.

[0054] During the second-level standard load calibration, the second lifting mechanism 74 rises, raising the loading frame 71 and suspension rod 72. Subsequently, the support column 762 rotates 36° (the rotation angle of the support column 762 can be measured by an encoder). At this point, the lowest weight 73 separates from the lowest support rod 763. From the bottom up, the second support rod 763 moves below the second weight 73. After the second lifting mechanism 74 descends to its initial position, the second support rod 763 supports the second through ninth weights 73, allowing the first weight 73 to be attached to the suspension rod 72 via the retaining ring 721, completing the second-level load loading.

[0055] At this time, the standard pressure applied to the tactile sensor 1 to be calibrated is: ; is the weight of the upper weight 73 hanging on the suspension rod 72; when loading at the second level, The value is 1 weight 73, when loaded at the third level, The value of is the weight of the first and second weights 73, and so on.

[0056] Similarly, when the hydraulic oil pressure in the inner cavity of the oil cylinder 6 and the oil storage cavity 411 reaches consistency, and the pressure on the flexible film 42 reaches uniformity, the computer collects the output of the currently calibrated tactile sensor 1 and compares it with the pressure in the oil storage cavity corresponding to the standard load applied by the weight loading mechanism 7 to achieve calibration of the load point of the calibrated tactile sensor 1.

[0057] Following the second-level load calibration method, weights 73 are cumulatively stacked and hung on the suspension rod 72 to achieve step-by-step standard load application. After the support column 762 rotates nine times (36° each rotation), all support rods 763 are separated from the weights 73, allowing all nine weights 73 to be hung on the suspension ring. This allows for precise pressure application to the tactile sensor 1 under test, from small to large pressures, across the measuring range, achieving wide-range, high-precision calibration.

[0058] Although the specific embodiments of the present invention are described above, those skilled in the art should understand that the specific embodiments described are merely illustrative and are not intended to limit the scope of the present invention. Equivalent modifications and changes made by those skilled in the art in accordance with the spirit of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A tactile sensor measurement and calibration device, characterized in that: include: A load-bearing platform, a gantry frame, a pressure loading mechanism, a piston, a cylinder and a weight loading mechanism for fixing the tactile sensor to be calibrated; The pressure loading mechanism includes an oil storage tank, an oil storage cavity is formed inside the oil storage tank, an opening is provided at the lower end of the oil storage tank, and the opening is sealed by a flexible film. The gantry frame is fixed to the top of the carrying platform, and the gantry frame is connected to a first lifting mechanism for driving the pressure loading mechanism to rise and fall. The first lifting mechanism is used to adjust the distance between the carrying platform and the flexible film to be equal to the thickness of the tactile sensor to be calibrated; The inner cavity of the oil cylinder is connected to the oil storage cavity through an oil pipe, the piston is slidably connected to the oil cylinder, and the standard load of the weight loading mechanism is loaded on the piston to pressurize the hydraulic oil in the oil storage cavity to form a standard pressure, causing the flexible film to deform downward, and the standard pressure is applied to the tactile sensor to be calibrated to achieve calibration of the tactile sensor to be calibrated.

2. The tactile sensor measurement and calibration device according to claim 1, wherein: The first lifting mechanism includes a ball screw and a screw nut spirally connected to the ball screw. The outer wall of the oil storage tank is rigidly provided with a flange. The screw nut is fixedly connected to the flange. The upper and lower ends of the ball screw are respectively rotatably connected to the gantry frame and the supporting platform. The supporting platform is connected to a first servo motor, and the first servo motor is connected to the ball screw.

3. The tactile sensor measurement and calibration device according to claim 1, wherein: The weight loading mechanism includes a loading frame, a suspension rod, several weights and a second lifting mechanism. A pressure head is provided on the inner side of the loading frame. The pressure head is located above the piston. During loading, the pressure head contacts the piston. The suspension rod is rigidly connected to the bottom of the loading frame. The second lifting mechanism is located at the bottom of the suspension rod and is used to lift the suspension rod. Several weights are mounted on the suspension rod, and the weight loading mechanism also includes a loading assembly for hanging several weights on the suspension rod step by step.

4. The tactile sensor measurement and calibration device according to claim 3, wherein: The loading assembly includes a support platform, the support platform is rotatably connected to a plurality of support columns, and a ring array of the plurality of support columns is arranged on the outside of the boom with the boom axis as the center; According to the number of the weights, each support column is provided with through holes spaced evenly from top to bottom, and the through holes are arranged in a spiral along the axis of the support column, and support rods for supporting the weights are inserted into the through holes; Each of the support columns is connected to a first sprocket, and the first sprockets are commonly connected to a chain. A second servo motor is also provided on the support platform, and the second servo motor is connected to a second sprocket, and the second sprocket is connected to the chain.

5. The tactile sensor measurement and calibration device according to claim 3, wherein: The bottom of the pressure head is a spherical surface.

6. The tactile sensor measurement and calibration device according to claim 1, wherein: It also includes an oil pressure meter, which has five detection sensing ends, one of which is used to detect the hydraulic oil pressure in the oil cylinder cavity; The remaining detection sensing ends are evenly arranged at the lower end of the oil storage tank close to the flexible film, and are used to detect whether the hydraulic oil pressure in the oil storage chamber is consistent with the hydraulic oil pressure in the oil cylinder cavity, and are also used to determine whether the pressure on the flexible film is uniform.

7. The tactile sensor measurement and calibration device according to claim 1, wherein: The device further comprises a laser interferometer connected to the carrying platform and used for measuring the distance between the carrying platform and the flexible film.

8. The tactile sensor measurement and calibration device according to claim 1, wherein: The middle section of the oil pipe is connected with an oil reservoir.

9. A tactile sensor metrology calibration method, characterized in that: Based on the metrological calibration device of a tactile sensor according to claim 6, the calibration method comprises the following steps: S1. Measuring the thickness of the tactile sensor to be calibrated, and controlling the first lifting mechanism to move according to the thickness of the tactile sensor to be calibrated until the distance between the carrying platform and the flexible film is equal to the thickness of the tactile sensor to be calibrated; S2. The weight loading mechanism applies a standard load to the piston, and the detection sensing end detects the hydraulic oil pressure in the cylinder cavity and the oil storage cavity respectively; when the pressure in the cylinder cavity and the oil storage cavity are equal, and the pressure on the flexible film is uniform, the computer collects the output of the current calibrated tactile sensor and compares it with the standard pressure in the oil storage cavity corresponding to the standard load applied by the weight loading mechanism to achieve calibration of the calibrated tactile sensor.

10. The tactile sensor measurement and calibration method according to claim 9, wherein: In step S2, the load point to be calibrated is determined according to the measuring range of the tactile sensor to be calibrated, and the weight loading mechanism applies corresponding standard loads on the piston step by step. Each time a standard load is applied, the corresponding standard pressure point of the tactile sensor to be calibrated is calibrated.

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