Agricultural material contact parameter measuring platform

Abstract

The invention provides an agricultural material contact parameter measuring platform which comprises a base, a mounting frame is arranged on the base, a rotating shaft is rotationally connected to the mounting frame, one end of the rotating shaft is connected with a driving device, the other end of the rotating shaft is connected with an angle detection device, a rotating platform is fixedly connected to the rotating shaft, and a to-be-measured plate is detachably connected to the rotating platform. A stand column is arranged on the rear side of the rotating platform, a height-adjustable altimeter is arranged at the upper end of the stand column, a distance measuring sensor is installed on the side, close to the stand column, of the rotating platform, a probe part of the distance measuring sensor faces the upper portion of the to-be-measured plate, and an angle ruler is further arranged on the to-be-measured plate. An image acquisition device is arranged on the left side of the base, an electric appliance cabinet is arranged on the base, a control module is installed in the electric appliance cabinet, and the image acquisition device, the human-computer interaction interface, the driving motor, the angle detection device and the distance measuring sensor are all electrically connected with the control module. The platform is quick and reliable in measurement response and small in error.

Description

Technical Field

[0001] The invention belongs to the technical field of measuring equipment, and in particular relates to a contact parameter measuring platform for agricultural materials. Background Art

[0002] With the advancement of agricultural mechanization, improving agricultural production efficiency and precision has become a core goal. In traditional agricultural operations, the contact parameters between materials (such as fruits and crops) and different materials have a significant impact on equipment optimization, operational performance, and production efficiency. These contact parameters are also essential elements in discrete element simulation. Agricultural material contact parameters primarily include the coefficient of restitution, static friction, and rolling friction, which are directly related to the stability of mechanical equipment and the reliability of simulation results.

[0003] Currently, several researchers at home and abroad have been researching methods and equipment for measuring contact parameters of agricultural materials. However, most of these efforts focus on measuring single parameters, such as the friction coefficient and the collision restitution coefficient, and these methods often have limitations in measurement accuracy and system versatility. Consequently, researchers are seeking to design measurement platforms with improved accuracy and versatility, such as a patent published by the State Intellectual Property Office of China: A System for Determining Contact Parameters of Bulk Materials [Publication No. CN116448629A, Application No. 2023104132827]. The patent discloses the following technical solution: a system for measuring contact parameters of bulk materials, characterized in that it includes a base for support; leveling nuts located at the four corners of the base and threadedly connected to the base; a galvanized steel plate located on the upper side of the base and rotatably connected to the base; a vertical bracket located at one corner of the upper side of the base and fixedly connected to the base; an adjustment mechanism located in the middle of the vertical bracket and rotatably connected to the vertical bracket; a blanking component passing through the middle of the adjustment mechanism and fixedly connected to the adjustment mechanism; a universal level located at one end of the upper side of the base and fixedly connected to the base; a mounting frame located at the upper part of the vertical bracket and fixedly connected to the vertical bracket; a self-locking handwheel located at the lower side of the mounting frame and fixedly connected to the mounting frame; an L-hole plate located at the lower part of the self-locking handwheel and fixedly connected to the self-locking handwheel; a steel wire rope, one end of which is fixedly connected to the galvanized steel plate, and the other end of which passes through the hole of the L-hole plate and fixedly connected to the self-locking handwheel; the L-frame located on the upper side of the base and fixedly connected to the base; and a funnel passing through the blanking component and fixedly connected to the blanking component.

[0004] The technical solution disclosed in the above patent can realize the measurement of the collision recovery coefficient, static friction coefficient and rolling friction coefficient of granular materials. However, in this solution, the galvanized steel plate is adjusted by pulling the wire rope through the handwheel. The adjustment process relies too much on experience and proficiency, and is prone to human errors, which has a great impact on the accuracy of the measurement results. In addition, when measuring the static friction coefficient and the rolling friction coefficient, it is necessary to manually stop the self-locking handwheel when observing the particle group sliding or rolling on the sheet. This process has high requirements on many factors such as the operator's reaction and hand speed, and is therefore prone to human errors, resulting in insufficient accuracy of the test results. Summary of the Invention

[0005] In view of this, an object of the present invention is to provide an efficient and high-precision agricultural material contact parameter measurement platform.

[0006] The objectives of the present invention can be achieved through the following technical solutions: An agricultural material contact parameter measurement platform, comprising a base, a mounting frame is provided on the base, a rotating shaft is rotatably connected to the mounting frame, one end of the rotating shaft is connected to a driving device, and the other end of the rotating shaft is connected to an angle detection device, a rotating platform is fixedly connected to the rotating shaft, and a plate to be measured is detachably connected to the rotating platform, a column is provided on the rear side of the rotating platform, a height-adjustable altimeter is provided on the upper end of the column, a ranging sensor is installed on the side of the rotating platform close to the column, the probe part of the ranging sensor is facing above the plate to be measured, and an angle ruler is also provided on the plate to be measured, a human-computer interaction interface is provided on the base at the right side of the rotating platform, an image acquisition device is provided on the left side of the base, an electrical cabinet is provided on the base, a control module is installed in the electrical cabinet, and the image acquisition device, human-computer interaction interface, drive motor, angle detection device and ranging sensor are all electrically connected to the control module.

[0007] In the aforementioned agricultural material contact parameter measurement platform, the distance sensor is a laser distance sensor, which is attached to the rear side of the rotating platform via a support arm. The distance sensor rotates with the rotating platform, ensuring that the distance sensor can effectively detect the displacement of the material on the rotating platform at any angle.

[0008] In the above-mentioned agricultural material contact parameter measurement platform, the four corners of the base are screwed with leveling nuts, which can ensure that the base is in a horizontal position, thereby ensuring the accuracy of the measurement data and reducing errors.

[0009] In the above-mentioned agricultural material contact parameter measurement platform, the image acquisition device is an industrial high-speed camera.

[0010] In the above-mentioned agricultural material contact parameter measurement platform, the control module is a PLC.

[0011] In the above-mentioned agricultural material contact parameter measurement platform, the driving motor is a servo motor, the driving motor is connected to the rotating shaft through a reducer, and the reducer is a harmonic reducer or a planetary gear reducer.

[0012] In the above-mentioned agricultural material contact parameter measurement platform, the inclined plate collision restitution coefficient is also measured by the following steps:

[0013] A1. Adjust the leveling nut to make the base level;

[0014] A2. Fix the plate to be tested on the rotating platform and use the level gauge to accurately calibrate the rotating platform;

[0015] A3. Input the preset platform tilt angle θ on the touch screen. The control module controls the drive motor to rotate according to the preset platform tilt angle θ, so that the rotating platform rotates to the target angle.

[0016] A4. Use an altimeter to determine the free-fall height H of the material. Then release the material and allow it to freely fall onto the inclined plate to be tested. The collision process is recorded in real time by video and / or photos using an image acquisition device to capture the motion state.

[0017] A5. Calculate the object's velocity v1 before and after the collision by analyzing its trajectory, and substitute it for The collision recovery coefficient e can be obtained;

[0018] Where: v 1n is the normal velocity of the material on the contact plane after collision, v 0n is the normal velocity of the material before collision on the contact plane, v1 is the velocity of the material after collision, v 1x is the velocity v1 in the X direction after the collision, v 1y is the velocity v1 in the y direction after the collision.

[0019] In the above-mentioned agricultural material contact parameter measurement platform, the flat plate collision restitution coefficient is also measured by the following steps:

[0020] B1. Adjust the leveling nut to make the base level;

[0021] B2. Fix the plate to be tested on the rotating platform and use the level gauge to accurately calibrate the rotating platform;

[0022] B3. Use an altimeter to determine the free-fall height H0 of the material, then release the material to allow it to freely fall onto the horizontal plate to be tested. The collision process is recorded in real time by video and / or photos using an image acquisition device to capture the motion state;

[0023] B4. Calculate the maximum rebound height H1 of the object upon collision by analyzing its motion trajectory and substitute it into the formula The collision recovery coefficient e can be obtained;

[0024] In the above-mentioned agricultural material contact parameter measurement platform, the static friction coefficient is also measured by the following steps:

[0025] C1. Adjust the leveling nut to make the base level;

[0026] C2. Fix the plate to be tested on the rotating platform and use the level gauge to accurately calibrate the rotating platform;

[0027] C3. Place the material on the plate to be tested and keep it stationary;

[0028] C4. Calibrate the material position through the distance measuring sensor, start the drive motor to start working, and the angle detection device monitors and records the rotation angle in real time;

[0029] C5. When the distance sensor detects that the material has moved, the distance sensor transmits a feedback signal to the control module, and the drive motor stops working. At this time, the angle detection device records the current stop angle and uploads it to the control module for storage. At the same time, it is displayed through the human-computer interaction interface. Substituting this angle into the formula f=tan(θ') can obtain the static friction coefficient f.

[0030] In the above-mentioned agricultural material contact parameter measurement platform, the rolling friction coefficient is also measured by the following steps:

[0031] D1. Adjust the leveling nut to make the base level;

[0032] D2. Fix the plate to be tested on the rotating platform and use the level gauge to accurately calibrate the rotating platform;

[0033] D3. Place the material on the plate to be tested and keep it still;

[0034] D4. Calibrate the material position through the distance measuring sensor, start the drive motor to start working, and the angle detection device monitors and records the rotation angle in real time;

[0035] D5. When the distance sensor detects that the material is rolling, the distance sensor transmits the feedback signal to the control module, and the drive motor stops working. At this time, the angle detection device records the current stop angle ω and uploads it to the control module for storage. At the same time, it is displayed through the human-computer interaction interface. Substitute this angle into the formula μ roll =tan(ω), the rolling friction coefficient μ can be obtained roll .

[0036] Compared with the existing technology, this agricultural material contact parameter measurement platform has the following advantages: it uses a drive motor for angle adjustment and cooperates with a laser ranging sensor to achieve faster response and smaller error accuracy, reaching the millisecond level; in addition, it cooperates with an angle detection device to achieve precise control and recording of the angle of the rotating platform, and the system response is faster and more reliable. It abandons the disadvantages of relying on human eye observation in the existing technology, reduces errors caused by slow human observation response and low control accuracy, and thus makes the measurement and calculation results more accurate; it has a higher degree of automation and intelligence, can significantly improve measurement efficiency and convenience, and can simultaneously measure the collision recovery coefficient, static friction coefficient and rolling friction coefficient. While ensuring measurement accuracy, it significantly reduces measurement costs and has high economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 2 is a schematic structural diagram of an agricultural material contact parameter measurement platform according to an embodiment.

[0038] Figure 2 4 is a control circuit diagram of a control module of the agricultural material contact parameter measurement platform of an embodiment.

[0039] Figure 3 1 is a schematic diagram showing the principle of measuring the recovery coefficient of an inclined plate collision using an agricultural material contact parameter measurement platform according to an embodiment.

[0040] Figure 4 1 is a flow chart of measuring the collision recovery coefficient using the agricultural material contact parameter measurement platform of an embodiment.

[0041] Figure 5 1 is a schematic diagram showing the principle of measuring the flat plate collision restitution coefficient using the agricultural material contact parameter measurement platform of an embodiment.

[0042] Figure 6 3. It is a schematic diagram of the principle of measuring the static friction coefficient of the agricultural material contact parameter measurement platform of the embodiment.

[0043] Figure 7 1 is a flow chart of the friction coefficient measurement process of the agricultural material contact parameter measurement platform of the embodiment.

[0044] Figure 83. It is a schematic diagram of the principle of measuring the rolling friction coefficient of the agricultural material contact parameter measurement platform of the embodiment.

[0045] In the figure, 1. base; 1a. leveling nut; 2. mounting bracket; 3. rotating shaft; 4. rotating platform; 4a. fixing clamp; 4b. horizontal frame; 5. driving motor; 6. angle detection device; 7. column; 8. human-computer interaction interface; 8a. touch screen; 8b. start button; 8c. shutdown button; 8d. emergency stop knob; 9. test board; 10. angle ruler; 11. reducer; 12. altimeter; 13. distance sensor; 14. image acquisition device; 15. electrical cabinet. DETAILED DESCRIPTION

[0046] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solutions of the present invention, but the present invention is not limited to these embodiments.

[0047] like Figure 1As shown, the present invention provides a platform for measuring contact parameters of agricultural materials, comprising a base 1, a mounting frame 2, a rotating shaft 3, a rotating platform 4, a drive motor 5, an angle detection device 6, a column 7, and a human-machine interface 8. Specifically, as shown in the figure, the mounting frame 2 comprises a pair of parallel brackets, with the ends of the rotating shaft 3 rotatably connected to the two brackets via bearings. The rotating platform 4 comprises two clamps 4a fixed to the center of the rotating shaft 3 and a crossbar 4b connecting the two clamps 4a. The rotating platform 4 rotates with the rotation of the rotating shaft 3. The rotating platform 4 clamps the test plate 9 with the two clamps 4a. An angle ruler 10 is mounted on the test plate 9, with its length perpendicular to the axis of the rotating shaft 3. A level is mounted on the angle ruler 10, which is used to observe and adjust the tilt angle of the test plate 9. One end of the rotating shaft 3 is connected to the drive motor 5 via a reducer 11, which drives the rotating shaft 3 for rotation or positioning. The reducer 11 is a harmonic reducer, but in other embodiments of the present invention, a planetary gear reducer can also be used instead. The other end of the rotating shaft 3 is connected to the angle detection device 6, which monitors the angle of rotation of the rotating shaft 3 in real time. In this embodiment, the angle detection device is implemented by a rotary encoder. The column 7 is arranged on the base 1 at the rear side of the rotating platform 4. The upper end of the column 7 is equipped with a height gauge 12, and the height gauge 12 can be adjusted at the upper end of the column 7. The rear side of the rotating platform 4 is fixedly connected to a distance sensor 13 through a support arm near the column 7. The distance sensor 13 is implemented by a laser distance sensor and is used to detect the displacement of the material on the test plate. The human-computer interaction interface 8 is arranged on the base 1 on the right side of the rotating platform 4, specifically including a touch screen 8a, a start button 8b, a shutdown button 8c and an emergency stop knob 8d. An industrial high-speed camera is provided on the other side of the rotating platform 4 as an image acquisition device 14, which is used to capture video and image information during the experiment. An electrical cabinet 15 is also provided on the base 1, in which a control module is installed. The control module is electrically connected to the industrial high-speed camera, the human-computer interaction interface 8, the drive motor 5, the angle detection device 6 and the ranging sensor 13 respectively. The control module can receive the angle data collected by the angle detection device 6, the displacement state data of the ranging sensor 13 and the instructions input by the human-computer interaction interface 8, and at the same time control the rotation of the drive motor 5 to adjust the inclination angle of the rotating platform 4.

[0048] It should be noted that in this embodiment, the control module utilizes a PLC, model FX3U-16MT / ES-A. Drive motor 5 utilizes a servo motor and its driver, leveraging its fast response, high speed, low inertia, and smooth rotation. The PLC outputs control pulses to precisely control the motor's rotation, thereby achieving precise positioning and precisely controlling the angle of rotating shaft 3.

[0049] Furthermore, in order to make the base 1 adaptable to more occasions, leveling nuts 1a are screwed on the four corners of the base 1, so that the base 1 can be ensured to be in a horizontal position through the leveling nuts 1a, thereby ensuring the accuracy of the measurement data and reducing errors.

[0050] This agricultural material contact parameter measurement platform can realize the measurement of collision recovery coefficient, including the measurement of inclined plate collision recovery coefficient and flat plate collision recovery coefficient.

[0051] According to Newton's definition, the collision restitution coefficient is the ratio of the separation velocity and the approach velocity of two objects along the normal direction of the contact point before and after the collision, usually expressed as e, as shown in formula (1).

[0052]

[0053] Where v1, v2 are the velocities of the two colliding objects after collision, v 10 , v 20 is the velocity of the two objects before collision.

[0054] The principle of measuring the inclined plate collision coefficient is as follows Figure 3 As shown in the figure, the speed of the inclined plate is 0 before and after the collision, the collision angle θ is 45°, and the collision recovery coefficient is:

[0055]

[0056] Where v 1n is the normal velocity of the material on the contact plane after collision, v 0n is the normal velocity of the material before collision on the contact plane.

[0057] The material starts to fall freely from a height H, and its speed before collision is:

[0058]

[0059] Where g is the acceleration due to gravity, which is 9.81 kg / m 3 .

[0060] Normal velocity before collision v 0n for:

[0061]

[0062] The velocity v1 after the collision is decomposed into the velocity v in the x direction 1x and the velocity v in the y direction 1y The x-direction is uniform linear motion, and the y-direction is uniformly accelerated linear motion. The relationship is as follows:

[0063]

[0064] The angle α between the velocity v1 and the Y direction, the velocity v 1x The angle β between the collision plane and the collision plane. According to the angle β, the normal velocity v after the collision is obtained 1n , their expressions are shown as follows:

[0065]

[0066] v 1n =v1sin(β) (10)

[0067] According to formula (2-10), the collision recovery coefficient e can be expressed as:

[0068]

[0069] Where: v 1n is the normal velocity of the material on the contact plane after collision, v 0n is the normal velocity of the material before collision on the contact plane, v1 is the velocity of the material after collision, v 1x is the velocity v1 in the X direction after the collision, v 1y is the velocity v1 in the y direction after the collision.

[0070] Combined with attachment Figure 4 The agricultural material contact parameter measurement platform measures the coefficient of restitution of the inclined plate collision through the following steps:

[0071] A1. Adjust the leveling nut 1a to make the base 1 level;

[0072] A2. Fix the test plate 9 (here, the test plate is a collision plate) on the rotating platform 4 and use the level of the angle ruler 10 to accurately calibrate the rotating platform 4 so that the test plate 9 is in a horizontal state;

[0073] A3. Input the preset platform tilt angle θ on the touch screen 8a. The control module controls the driving motor 5 to rotate according to the preset platform tilt angle θ, so that the rotating platform 4 drives the test plate 9 to rotate to the target angle;

[0074] A4. Determine the free-fall height H of the material using the altimeter 12, then release the material to allow it to freely fall onto the inclined test plate 9. The collision process is recorded in real time by video and / or photos using the image acquisition device 14 to capture the motion state.

[0075] A5. Calculate the object's velocity v1 before and after the collision by analyzing its trajectory and substitute it into the formula The collision recovery coefficient e can be obtained.

[0076] The principle of measuring the plate collision coefficient is as follows Figure 5As shown in the figure, A is the material before collision, A' is the material after collision, and B is the test plate 9. During the test, the speed of the test plate 9 is always 0, so the collision recovery coefficient is recorded as:

[0077]

[0078] Wherein v'0 is the speed of the material before contacting the plate 9 to be tested, and v'1 is the speed of the material after contacting the plate 9 to be tested.

[0079] By analyzing the motion of materials before and after collision, we can obtain the following according to the law of conservation of energy:

[0080]

[0081] Where H0 is the initial height of the material before free fall, and H1 is the maximum rebound height of the material after it contacts the plate.

[0082] Combining formula (12-14), we can get:

[0083]

[0084] Combined with attachment Figure 4 The agricultural material contact parameter measurement platform measures the flat plate collision restitution coefficient through the following steps:

[0085] B1. Adjust the leveling nut 1a to make the base 1 level;

[0086] B2. Fix the test plate 9 (here, the test plate is a collision plate) on the rotating platform 4 and use the level of the angle ruler 10 to accurately calibrate the rotating platform 4;

[0087] B3. Use the altimeter 12 to determine the free-fall height H0 of the material, then release the material to allow it to freely fall onto the horizontal test plate 9. The collision process is recorded in real time by video and / or photos using the image acquisition device 14 to capture the motion state;

[0088] B4. Calculate the maximum rebound height H1 of the object upon collision by analyzing its motion trajectory and substitute it into the formula The collision recovery coefficient e can be obtained.

[0089] This agricultural material contact parameter measurement platform can realize the measurement of friction coefficient, including static friction coefficient measurement and rolling friction coefficient measurement.

[0090] The static friction coefficient was determined by the plate tilting method. Figure 6 As shown in the figure, according to the force of the object being measured on the inclined plate, we can get:

[0091] fmgcos(θ')=mgsin(θ') (16)

[0092] Where f is the static friction coefficient. Simplifying equation (16) yields:

[0093] f=tan(θ') (17)

[0094] Combine Figure 7 The agricultural material contact parameter measurement platform measures the static friction coefficient through the following steps:

[0095] C1. Adjust the leveling nut 1a to make the base 1 level;

[0096] C2. Fix the test board (here, the test board is a contact board) on the rotating platform 4 and use the level of the angle ruler 10 to accurately calibrate the rotating platform 4 so that the test board 9 is in a horizontal state;

[0097] C3. Place the material on the test plate 9 and keep it stationary;

[0098] C4. Calibrate and start the drive motor 5 through the laser ranging sensor to start working, and the angle detection device 6 monitors and records the rotation angle in real time;

[0099] C5. When the laser ranging sensor detects that the material has moved, the laser ranging sensor transmits a feedback signal to the PLC control module, and the drive motor 5 stops working. At this time, the angle detection device 6 records the current stop angle and uploads it to the control module for storage, and displays it through the human-computer interaction interface 8. Substituting this angle into the formula f=tan(θ') can obtain the static friction coefficient f.

[0100] In this embodiment, the rolling friction coefficient is measured using a dimensionless rolling friction coefficient, and the principle is as follows: Figure 8 As shown, the rolling friction coefficient is expressed as:

[0101] μ r =tan(ω) (17)

[0102] Reference Figure 7 The agricultural material contact parameter measurement platform measures the static friction coefficient through the following steps:

[0103] D1. Adjust the leveling nut 1a to make the base 1 level;

[0104] D2. Fix the test board (here, the test board is a contact board) on the rotating platform 4 and use the level of the angle ruler 10 to accurately calibrate the rotating platform 4 so that the test board 9 is in a horizontal state;

[0105] D3. Place the material on the test plate 9 and keep it stationary;

[0106] D4. Calibrate and start the drive motor 5 through the laser ranging sensor to start working, and the angle detection device 6 monitors and records the rotation angle in real time;

[0107] D5. When the laser ranging sensor detects that the material is rolling, the laser ranging sensor transmits the feedback signal to the PLC control module, and the drive motor 5 stops working. At this time, the angle detection device 6 records the current stop angle ω and uploads it to the control module for storage. At the same time, it is displayed through the human-computer interaction interface 8. Substitute this angle into the formula μ roll =tan(ω), the rolling friction coefficient μ can be obtained roll .

[0108] Through clever design, this device can measure the coefficient of restitution of inclined plate collision, coefficient of restitution of flat plate collision, coefficient of static friction, coefficient of rolling friction, etc. It combines multiple test sets into one set of equipment, simplifies the experimental device, improves the efficiency of detection, and also ensures the high precision, high efficiency and high reliability requirements of the measurement results.

[0109] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Persons skilled in the art may make various modifications, additions, or substitutions to the described specific embodiments without departing from the spirit of the present invention or exceeding the scope of the appended claims.

Claims

1. A platform for measuring contact parameters of agricultural materials, comprising a base (1), a mounting frame (2) provided on the base (1), a rotating shaft (3) rotatably connected to the mounting frame (2), one end of the rotating shaft (3) being connected to a driving device, the other end of the rotating shaft (3) being connected to an angle detection device (6), a rotating platform (4) being fixedly connected to the rotating shaft (3), a plate to be measured (9) being detachably connected to the rotating platform (4), a column (7) being provided at the rear side of the rotating platform (4), a height-adjustable altimeter (12) being provided at the upper end of the column (7), and a rotating platform (4) being provided on a side close to the column (7). A distance measuring sensor (13) is provided, wherein a probe portion of the distance measuring sensor (13) faces above the plate to be measured (9), and an angle ruler (10) is further provided on the plate to be measured (9). A human-machine interaction interface (8) is provided on the base (1) at the right side of the rotating platform (4), and an image acquisition device (14) is provided on the left side of the base (1). An electrical cabinet (15) is provided on the base (1), and a control module is installed in the electrical cabinet (15). The image acquisition device (14), the human-machine interaction interface (8), the drive motor (5), the rotary encoder, and the distance measuring sensor (13) are all electrically connected to the control module.

2. The agricultural material contact parameter measurement platform according to claim 1, characterized in that: The distance measuring sensor (13) is a laser distance measuring sensor (13), and the distance measuring sensor (13) is highly connected to the rear side of the rotating platform (4) via a supporting arm.

3. The agricultural material contact parameter measurement platform according to claim 1 or 2, characterized in that: The four corners of the base (1) are screwed with leveling nuts (1a).

4. The agricultural material contact parameter measurement platform according to claim 1 or 2, characterized in that: The image acquisition device (14) is an industrial high-speed camera.

5. The agricultural material contact parameter measurement platform according to claim 1 or 2, characterized in that: The control module is a PLC.

6. The agricultural material contact parameter measurement platform according to claim 1 or 2, characterized in that: The drive motor (5) is a servo motor, and the drive motor (5) is connected to the rotating shaft (3) via a reducer (11), and the reducer (11) is a harmonic reducer (11) or a planetary gear reducer (11).

7. The agricultural material contact parameter measurement platform according to claim 1 or 2, characterized in that: The following steps are also included to determine the coefficient of restitution of the inclined plate impact: A1. Adjust the base (1) so that the base (1) is level; A2. Fix the test plate (9) on the rotating platform (4) and use the angle ruler (10) to accurately calibrate the rotating platform (4); A3. Inputting a preset platform tilt angle θ into the touch screen (8a), the control module controls the driving motor (5) to rotate according to the preset platform tilt angle θ, so that the rotating platform (4) rotates to the target angle; A4. Using an altimeter (12), determine the free-fall height H of the material, then release the material to allow it to freely fall onto the inclined test plate (9). The collision process is recorded in real time by video and / or photos using an image acquisition device (14) to capture the motion state; A5. Calculate the object's velocity v1 before and after the collision by analyzing its trajectory and substitute it into the formula The collision recovery coefficient e can be obtained; Where: v 1n is the normal velocity of the material after collision in the plane of the contact plate (9) to be tested, v 0n is the normal velocity of the material before collision on the plane of the test plate (9), v1 is the velocity of the material after collision, v 1x is the velocity v1 in the X direction after the collision, v 1y is the velocity v1 in the y direction after the collision.

8. The agricultural material contact parameter measurement platform according to claim 1 or 2, characterized in that: It also includes the determination of the coefficient of restitution of a flat plate impact by the following steps: B1. Adjust the base (1) so that the base (1) is level; B2. Fix the test plate (9) on the rotating platform (4) and use the angle ruler (10) to accurately calibrate the rotating platform (4); B3. Using an altimeter (12), determine the free-fall height H0 of the material, then release the material to allow it to freely fall onto the horizontal test plate (9). The collision process is recorded in real time by video and / or photos using an image acquisition device (14) to capture the motion state; B4. Calculate the maximum rebound height H1 of the object upon collision by analyzing its motion trajectory and substitute it into the formula The collision recovery coefficient e can be obtained; 9. The agricultural material contact parameter measurement platform according to claim 1 or 2, characterized in that: It also includes the determination of the static friction coefficient by the following steps: C1. Adjust the base (1) so that the base (1) is level; C2. Fix the test plate (9) on the rotating platform (4) and use the angle ruler (10) to accurately calibrate the rotating platform (4); C3. Place the material on the test plate (9) and keep it stationary; C4. Calibrate the material position through the distance measuring sensor (13), start the driving motor (5) to start working, and the angle detection device (6) monitors and records the rotation angle in real time; C5. When the distance sensor (13) detects that the material has moved, the distance sensor (13) transmits a feedback signal to the control module, and the drive motor (5) stops working. At this time, the angle detection device (6) records the current stop angle and uploads it to the control module for storage, and displays it through the human-computer interaction interface (8). Substituting this angle into the formula f=tan(θ') can obtain the static friction coefficient f.

10. The agricultural material contact parameter measurement platform according to claim 1 or 2, characterized in that: The rolling friction coefficient is determined by the following steps: D1. Adjust the base (1) so that the base (1) is level; D2. Fix the test plate (9) on the rotating platform (4) and use the angle ruler (10) to accurately calibrate the rotating platform (4); D3. Place the material on the test plate (9) and keep it stationary; D4. Calibrate the material position through the distance measuring sensor (13), start the driving motor (5) to start working, and the angle detection device (6) monitors and records the rotation angle in real time; D5. When the distance sensor (13) detects that the material is rolling, the distance sensor (13) transmits a feedback signal to the control module, and the drive motor (5) stops working. At this time, the angle detection device (6) records the current stop angle ω and uploads it to the control module for storage, and displays it through the human-computer interaction interface (8). Substitute this angle into the formula μ roll =tan(ω), the rolling friction coefficient μ can be obtained roll .

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