Experimental device and method for calculating two recovery coefficients of multi-dimensional rigid body by considering rotation

Abstract

The invention belongs to the technical field of mechanics and engineering, and discloses an experimental device and method for calculating two recovery coefficients of a multi-dimensional rigid body considering rotation, the experimental device comprises a bottom plate and a frame, the frame is connected with the bottom plate through supports, and the supports are arranged at the two ends of the bottom plate in pairs; a first clamp is arranged on the support, the first clamp is used for clamping two acrylic plates which are arranged in parallel, and a gap is formed between the two acrylic plates which are arranged in parallel; a lifting table is arranged at the two ends of the bottom plate and between the two supports, an inclined panel is arranged on the lifting table, the inclined panel is located between the two parallel acrylic plates, and inclined plane supporting strips are arranged on the inclined panel; and a second clamp is arranged at the top of the frame and above a gap between the two acrylic plates which are arranged in parallel, and the second clamp is used for clamping a rigid body to be released. According to the invention, collision between metals of different materials and planar rigid bodies of different shapes can be simulated, various recovery coefficients can be measured and solved, and the measurement accuracy of the recovery coefficients is improved.

Description

Technical Field

[0001] The invention relates to the field of mechanics and engineering technology, and in particular to an experimental device and method for calculating two restitution coefficients of a multi-dimensional rigid body taking rotation into consideration. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] The collision problem is one of the most basic problems in mechanics research. Rigid body collisions can be seen everywhere in daily life, such as common rockfall collisions, particle collisions, etc. The collision behavior between rigid bodies will significantly change the motion state of the rigid body. When numerically simulating the collision process, the commonly used mechanical models are divided into two categories. One is to simulate the collision behavior by changing the force through the continuous contact force model, and the other is to ignore the collision process and directly consider the changes in the physical quantities of the system (velocity, impulse or energy) before and after the collision. The realization of these two methods is closely related to the collision restitution coefficient, so the restitution coefficient plays a great role in the prediction of collision behavior. Accurate measurement of the collision restitution coefficient helps to more accurately predict the mechanical behavior and phenomena of rigid bodies.

[0004] The collision restitution coefficient is a physical parameter that reflects the collision of the collision body before and after the collision. It is affected by many factors such as material, collision angle, impact speed, etc. Common restitution coefficients include Newton's restitution coefficient, Poisson's restitution coefficient, Stronge's restitution coefficient, and Hedrih's restitution coefficient. Most of the existing experiments for measuring the restitution coefficient are the measurement of the Newton restitution coefficient of particles and planes, and most of the measurement processes are relatively simple. There is still room for further improvement in the accurate measurement of the restitution coefficient. Summary of the invention

[0005] In order to solve the above problems, the present invention proposes an experimental device and method for calculating two coefficients of restitution of multi-dimensional rigid bodies taking rotation into consideration, which can simulate the collision of metals of different materials with planar rigid bodies of different shapes, can measure and solve multiple coefficients of restitution, and improve the measurement accuracy of the coefficient of restitution.

[0006] In order to achieve the above object, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides an experimental device for calculating two restitution coefficients of a multi-dimensional rigid body taking rotation into consideration, comprising a base plate and a frame, wherein the frame is connected to the base plate via supports, and the supports are arranged in pairs at both ends of the base plate;

[0008] A first clamp is provided on the support, and the first clamp is used to clamp two acrylic plates placed in parallel, and a gap is provided between the two acrylic plates placed in parallel;

[0009] A lifting platform is provided between two supports at both ends of the bottom plate, and an inclined panel is provided on the lifting platform. The inclined panel is located between two parallel acrylic panels, and an inclined support strip is provided on the inclined panel.

[0010] A second clamp is provided on the top of the frame and above the gap between the two parallel acrylic plates, and the second clamp is used to clamp the rigid body to be released.

[0011] As an optional implementation, the inclined panel can be mounted on the lifting platform at both ends, or one end can be mounted on the lifting platform and the other end can be fixed on the support, and the inclination angle of the inclined panel can be controlled by adjusting the height of the lifting platform.

[0012] As an optional implementation, the inclined support bars are metal bars made of different materials, which are used to simulate the collision between metals of different materials and planar rigid bodies of different shapes.

[0013] As an optional implementation, the rigid body to be released is a rigid body of a different shape, and its position and posture are adjusted by a second clamp.

[0014] As an optional implementation, it also includes a high-speed camera for capturing a complete picture of the rigid body colliding with the inclined support bar.

[0015] In a second aspect, the present invention provides an experimental method for calculating two restitution coefficients of a multi-dimensional rigid body taking into account rotation, comprising the following steps:

[0016] S1: Assemble the rigid body collision test platform, clamp the rigid body to be tested to the second fixture on the top of the frame, and adjust its position and posture;

[0017] S2: Adjust the position of the high-speed camera so that it can capture the complete picture of the rigid body colliding with the inclined support bar, adjust the camera frame rate, and start the video recording process when the rigid body is released from the second fixture;

[0018] S3: Import the video from the high-speed camera into the software tracker, track the center of mass position, velocity and acceleration of the rigid body through the tracker software and output the results;

[0019] S4: When a rigid body collides with another body in two-dimensional motion without rotation, its center of mass velocity is the same as the velocity of the collision point. The relative velocity of the collision point before and after the collision can be obtained by taking the average of the center of mass velocities of the previous and next frames to obtain the relative collision velocity. Substituting it into the formula of Newton's coefficient of restitution can obtain the coefficient of restitution.

[0020] S5: When a rigid body performs two-dimensional motion including rotation and collides, first use the tracker software to obtain the velocity of the rigid body's center of mass, then find the velocity of the collision point based on the velocity of the rigid body's center of mass. After calculating the relative velocity before and after the collision point, substitute it into the Newton's coefficient of restitution formula to obtain the coefficient of restitution.

[0021] As an optional implementation, the velocity of the collision point is calculated based on the velocity of the center of mass of the rigid body, and the formula is:

[0022] v A =v O +ω×r OA

[0023] Among them, v O is the velocity of the center of mass, r OA is the radius vector from the center of mass to the collision contact point, and ω is the angular velocity of the rigid body rotation.

[0024] As an optional implementation, the Possion recovery coefficient can also be calculated. The specific steps are as follows:

[0025] S1: Assemble the rigid body collision test platform, clamp the rigid body to be tested to the second fixture on the top of the frame, and adjust its position and posture;

[0026] S2: Adjust the position of the high-speed camera so that it can capture the complete picture of the rigid body colliding with the inclined support bar, adjust the camera frame rate, and start the video recording process when the rigid body is released from the second fixture;

[0027] S3: Import the video from the high-speed camera into the software tracker, track the center of mass position, velocity and acceleration of the rigid body through the tracker software and output the results;

[0028] S4: When the rigid body performs two-dimensional motion, the maximum impact force during the collision is detected by the pressure sensor, which is used as the force at the end of the compression phase and the initial time of the recovery phase. The high-speed camera determines the starting time of the collision compression phase and the recovery phase. The force corresponding to the intermediate moments is solved by the interpolation method. Finally, the impulse ratio of the collision recovery phase and the collision compression phase is calculated to solve the Possion recovery coefficient.

[0029] As an optional implementation, the calculation formula of the Possion recovery coefficient is:

[0030]

[0031] Where F is the contact force, t c is the compression end time, t e is the end time of the entire collision process, t s The collision behavior start time.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] The present invention discloses an experimental device and method for calculating two coefficients of restitution of a multi-dimensional rigid body taking rotation into consideration. Two parallel acrylic plates are used to force the rigid body to make a plane free fall, making the measurement of physical quantities simpler. The initial position of the fall of the rigid body is controlled by adjusting the position of the second clamp on the sixth optical bar. The falling posture of the rigid body can be adjusted by adjusting the clamping state of the second clamp and the rigid body. The inclined support bar is a metal bar of different materials, which can simulate the collision of metals of different materials with plane rigid bodies of different shapes. During the rigid body collision process, a high-speed camera is used to record the video of the entire collision process, and the software is used to process the video to extract the parameters such as the center of mass position and speed of the rigid body. The relative speed before and after the collision point is solved by an algorithm, and then brought into the formula to calculate the Newton and energy restitution coefficients. At the same time, the Poisson restitution coefficient can be calculated according to the pressure change before and after the collision. It is possible to measure and solve a variety of restitution coefficients, and improve the measurement accuracy of the restitution coefficient.

[0034] Advantages of additional aspects of the present invention will be given in part in the following description, and in part will become obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0036] Figure 1 Schematic diagram of the rigid body collision process;

[0037] Figure 2 A schematic diagram of the overall structure of an experimental device for calculating two coefficients of restitution of a multi-dimensional rigid body taking rotation into consideration provided in Example 1 of the present invention;

[0038] Figure 3 A schematic diagram of a portion of the structure of an experimental device for calculating two coefficients of restitution of a multi-dimensional rigid body taking rotation into consideration provided in Example 1 of the present invention;

[0039] Figure 4 for Figure 3 A structural diagram of the main view;

[0040] Figure 5 A flow chart of an experimental method for calculating two coefficients of restitution of a multi-dimensional rigid body taking rotation into account provided in Example 1 of the present invention.

[0041] Among them, 1. bottom plate, 2. support, 3. first lifting platform 1, 4. first light rod, 5. second light rod, 6. first cross clamp, 7. second cross clamp, 8. third cross clamp, 9. fourth cross clamp, 10. fifth cross clamp, 11. sixth cross clamp, 12. third light rod, 13. fourth light rod, 14. acrylic plate, 15. fifth light rod, 16. second lifting platform, 17. sixth light rod, 18. second clamp, 19. inclined support bar, 20. table, 21. high-speed camera. DETAILED DESCRIPTION

[0042] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0043] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0044] It should be noted that the terms used herein are only for describing specific embodiments, and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that the terms "include" and "have" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0045] In the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0046] Figure 1 It is a schematic diagram of the collision process of two rigid bodies. The Newton restitution coefficient is a way to measure the energy dissipation behavior in the collision process based on the conservation of momentum before and after the collision, using the ratio of the normal contact relative velocity of the contact point before and after the collision. The expression is:

[0047]

[0048] in, is the relative velocity before the collision, is the relative velocity after the collision, where v1 and v′1 are the normal velocities of the contact point of rigid body 1 before and after the collision, and v2 and v′2 are the normal velocities of the contact point of rigid body 2 before and after the collision.

[0049] The Possion restitution coefficient divides the collision process into two stages: compression and recovery. The energy dissipation of the collision process is measured by the ratio of the impulse in the collision recovery stage to the impulse in the compression stage. Its expression is:

[0050]

[0051] Where F is the contact force, t c is the compression end time, t e is the end time of the entire collision process, t s The collision behavior start time.

[0052] Example 1

[0053] like Figure 2-4 As shown, this embodiment provides an experimental device for calculating two restitution coefficients of a multi-dimensional rigid body taking rotation into consideration, comprising a base plate 1 and a frame. The frame is connected to the base plate 1 via supports 2. The supports 2 are arranged in pairs at both ends of the base plate 1. There is a pair of supports 2 at each of the left and right ends of the base plate 1, which is convenient for supporting the frame and two parallel acrylic plates 14.

[0054] A first clamp is provided on the support 2, and the first clamp is used to clamp two parallel acrylic plates 14. A gap is provided between the two parallel acrylic plates 14. The acrylic plates 14 are two rectangular transparent plastic plates. There is a 5mm gap between the two acrylic plates 14. When the rigid body moves inside the gap, the two parallel acrylic plates 14 can force the rigid body to perform two-dimensional motion, making the measurement of physical quantities simpler.

[0055] A lifting platform (3, 16) is provided between the two ends of the bottom plate 1 and the two supports 2. An inclined panel is provided on the lifting platform (3, 16). The inclined panel is located between two acrylic panels 14 placed in parallel. The angle of the inclined panel is adjustable. An inclined support bar 19 is provided on the inclined panel. The inclined support bar 19 is a metal bar made of different materials and is used to simulate the collision between metals of different materials and plane rigid bodies of different shapes. The inclined panel can be mounted on the lifting platform (3, 16) at both ends, or one end can be mounted on the lifting platform (3, 16) and the other end can be fixed on the support 2. The inclination angle of the inclined panel can be controlled by adjusting the height of the lifting platform (3, 16).

[0056] A second clamp 18 is provided on the top of the frame and above the gap between the two parallel acrylic plates 14. The second clamp 18 is used to clamp the rigid body to be released. The rigid body to be released is a rigid body of different shapes, and its position and posture are adjusted by the second clamp 18.

[0057] The experimental device also includes a high-speed camera 21 for capturing a complete picture of the rigid body colliding with the inclined support bar 19 .

[0058] The frame is composed of multiple light rods and multiple cross clamps, wherein four vertical light rods are respectively inserted into the through holes of the support 2, and a cross clamp is placed between every two closest light rods to build the frame. A sixth light rod 17 is provided in the horizontal direction on the top of the frame. The sixth light rod 17 is parallel to the gap between two parallel acrylic plates 14 and is located above the gap. A second clamp 18 is provided on the sixth light rod 17, and its position can be adjusted by sliding on the sixth light rod 17 to adjust the release of the rigid body at different positions. It can also change the angle of the rigid body at the initial collision when clamping.

[0059] Example 2

[0060] like Figure 5 As shown, this embodiment provides an experimental method for calculating two restitution coefficients of a multi-dimensional rigid body taking rotation into consideration, comprising the following steps:

[0061] S1: Assemble the rigid body collision test platform, clamp the rigid body to be tested to the second fixture on the top of the frame, and adjust its position and posture;

[0062] S2: Adjust the position of the high-speed camera so that it can capture the complete picture of the rigid body colliding with the inclined support bar, adjust the camera frame rate, and start the video recording process when the rigid body is released from the second fixture;

[0063] S3: Import the video from the high-speed camera into the software tracker, track the center of mass position, velocity and acceleration of the rigid body through the tracker software and output the results;

[0064] S4: When a rigid body collides with another body in two-dimensional motion without rotation, its center of mass velocity is the same as the velocity of the collision point. The relative velocity of the collision point before and after the collision can be obtained by taking the center of mass velocity of the previous and next frames as the average value to obtain its relative collision velocity. In addition, when analyzing the rotation velocity before and after the collision (in order to accurately measure the rotation velocity and reduce the error, it is necessary to draw different colored lines on the steel ball along the equator with a marker in advance, and the marker line should face the high-speed camera during the experiment), take the rotation angle of the steel ball in ten frames (measured using a tracker protractor) divided by the time (the time can be obtained from the frame rate, such as 500 frames per second, then the time is 10*1 / 500 seconds), and substitute it into the formula of Newton's coefficient of restitution to obtain the coefficient of restitution;

[0065] S5: When a rigid body performs two-dimensional motion including rotation and collides, first use the tracker software to obtain the velocity of the rigid body's center of mass, then find the velocity of the collision point based on the velocity of the rigid body's center of mass. After calculating the relative velocity before and after the collision point, substitute it into the Newton's coefficient of restitution formula to obtain the coefficient of restitution.

[0066] The two-dimensional motion of a rigid body includes or does not include rotation. The specific operation is: wrapping paper strips of different lengths on the rigid body perpendicular to the equator, and then releasing the rigid body by pinching the ends of the paper strips to obtain the rigid body rotation before the collision. The length of the paper strips is different, and the initial rotation speed of the rigid body before the collision is different. The specific rotation speed needs to be precisely measured by the tracker software. If the rigid body is released directly, the rigid body moves downward and then collides, then the two-dimensional motion before the collision does not include rotation.

[0067] Among them, the velocity of the collision point is calculated based on the velocity of the center of mass of the rigid body, and the formula is:

[0068] v A =v O +ω×r OA

[0069] Among them, v O is the velocity of the center of mass, r OA is the radius vector from the center of mass to the collision contact point, and ω is the angular velocity of the rigid body rotation.

[0070] This experimental device can also calculate the Possion recovery coefficient. The specific steps are as follows:

[0071] S1: Assemble the rigid body collision test platform, clamp the rigid body to be tested to the second fixture on the top of the frame, and adjust its position and posture;

[0072] S2: Adjust the position of the high-speed camera so that it can capture the complete picture of the rigid body colliding with the inclined support bar, adjust the camera frame rate, and start the video recording process when the rigid body is released from the second fixture;

[0073] S3: Import the video from the high-speed camera into the software tracker, track the center of mass position, velocity and acceleration of the rigid body through the tracker software and output the results;

[0074] S4: When the rigid body performs two-dimensional motion, the maximum impact force during the collision is detected by the pressure sensor, which is used as the force at the end of the compression phase and the initial time of the recovery phase. The high-speed camera determines the starting time of the collision compression phase and the recovery phase. The force corresponding to the intermediate moments is solved by the interpolation method. Finally, the impulse ratio of the collision recovery phase and the collision compression phase is calculated to solve the Possion recovery coefficient.

[0075] It should be noted that the above modules correspond to the steps described in Example 1, and the examples and application scenarios implemented by the above modules and the corresponding steps are the same, but are not limited to the contents disclosed in the above Example 1. It should be noted that the above modules, as part of the system, can be executed in a computer system such as a set of computer executable instructions.

[0076] In further embodiments, there is also provided:

[0077] An electronic device includes a memory and a processor, and computer instructions stored in the memory and executed on the processor, wherein when the computer instructions are executed by the processor, the method described in Embodiment 1 is performed. For the sake of brevity, it will not be described in detail here.

[0078] It should be understood that in this embodiment, the processor may be a central processing unit CPU, and the processor may also be other general-purpose processors, digital signal processors DSP, application-specific integrated circuits ASIC, off-the-shelf programmable gate arrays FPGA or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0079] The memory may include a read-only memory and a random access memory, and provide instructions and data to the processor. A portion of the memory may also include a non-volatile random access memory. For example, the memory may also store information about the device type.

[0080] A computer-readable storage medium is used to store computer instructions, and when the computer instructions are executed by a processor, the method described in Example 1 is completed.

[0081] The method in Example 1 can be directly embodied as a hardware processor, or a combination of hardware and software modules in the processor. The software module can be located in a mature storage medium in the field such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, or an electrically erasable programmable memory, a register, etc. The storage medium is located in the memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware. To avoid repetition, it is not described in detail here.

[0082] A computer program product includes a computer program, and when the computer program is executed by a processor, the method described in embodiment 1 is implemented.

[0083] The present invention also provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product includes computer executable instructions, such as instructions included in a program module, which are executed in a device on a real or virtual processor of the target to perform the process / method as described above. Typically, program modules include routines, programs, libraries, objects, classes, components, data structures, etc. that perform specific tasks or implement specific abstract data types. In various embodiments, the functions of program modules can be combined or divided between program modules as needed. Machine executable instructions for program modules can be executed in local or distributed devices. In distributed devices, program modules can be located in local and remote storage media.

[0084] The computer program code for implementing the method of the present invention can be written in one or more programming languages. These computer program codes can be provided to the processor of a general-purpose computer, a special-purpose computer or other programmable data processing device, so that the program code, when executed by the computer or other programmable data processing device, causes the function / operation specified in the flow chart and / or block diagram to be implemented. The program code can be executed completely on a computer, partially on a computer, as an independent software package, partially on a computer and partially on a remote computer or completely on a remote computer or server.

[0085] In the context of the present invention, computer program codes or related data may be carried by any appropriate carrier to enable a device, apparatus or processor to perform the various processes and operations described above. Examples of carriers include signals, computer readable media, and the like. Examples of signals may include electrical, optical, radio, acoustic or other forms of propagation signals, such as carrier waves, infrared signals, and the like.

[0086] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with this embodiment can be implemented in electronic hardware or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0087] Although the above describes the specific implementation mode of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without creative work are still within the scope of protection of the present invention.

Claims

1. An experimental device for calculating two restitution coefficients of a multidimensional rigid body considering rotation, characterized in that: It includes a bottom plate and a frame, wherein the frame is connected to the bottom plate through a support, and the support is arranged in pairs at both ends of the bottom plate; The support is provided with a first clamp, and the first clamp is used to clamp two acrylic plates placed in parallel, and a gap is provided between the two acrylic plates placed in parallel; A lifting platform is provided between the two ends of the bottom plate and the two supports, and an inclined panel is provided on the lifting platform. The inclined panel is located between two parallel acrylic panels, and an inclined support strip is provided on the inclined panel; A second clamp is provided on the top of the frame and above the gap between the two parallel acrylic plates, and the second clamp is used to clamp the rigid body to be released.

2. The experimental device for calculating two coefficients of restitution of a multi-dimensional rigid body taking rotation into consideration as claimed in claim 1, characterized in that: The inclined panel can be mounted on the lifting platform at both ends, or mounted on the lifting platform at one end and fixed on the support at the other end, and the inclination angle of the inclined panel can be controlled by adjusting the height of the lifting platform.

3. The experimental device for calculating two coefficients of restitution of a multi-dimensional rigid body taking rotation into consideration as claimed in claim 1, characterized in that: The inclined support bars are metal bars of different materials, and are used to simulate the collision between metals of different materials and planar rigid bodies of different shapes.

4. The experimental device for calculating two coefficients of restitution of a multi-dimensional rigid body taking rotation into consideration as claimed in claim 1, characterized in that: The rigid body to be released is a rigid body of different shapes, and its position and posture are adjusted by the second clamp.

5. The experimental device for calculating two restitution coefficients of a multi-dimensional rigid body taking rotation into consideration as claimed in claim 1, characterized in that: It also includes a high-speed camera to capture the complete picture of the rigid body colliding with the ramp support bar.

6. An experimental method for calculating two coefficients of restitution of a multidimensional rigid body taking into account rotation, characterized in that: The following steps are involved: S1: Assemble the rigid body collision test platform, clamp the rigid body to be tested to the second fixture on the top of the frame, and adjust its position and posture; S2: Adjust the position of the high-speed camera so that it can capture the complete picture of the rigid body colliding with the inclined support bar, adjust the camera frame rate, and start the video recording process when the rigid body is released from the second fixture; S3: Import the video from the high-speed camera into the software tracker, track the center of mass position, velocity and acceleration of the rigid body through the tracker software and output the results; S4: When a rigid body collides with another body in two-dimensional motion without rotation, its center of mass velocity is the same as the velocity of the collision point. The relative velocity of the collision point before and after the collision can be obtained by taking the average of the center of mass velocities of the previous and next frames to obtain the relative collision velocity. Substituting it into the formula of Newton's coefficient of restitution can obtain the coefficient of restitution. S5: When a rigid body performs two-dimensional motion including rotation and collides, first use the tracker software to obtain the velocity of the rigid body's center of mass, then find the velocity of the collision point based on the velocity of the rigid body's center of mass. After calculating the relative velocity before and after the collision point, substitute it into the Newton's coefficient of restitution formula to obtain the coefficient of restitution.

7. The experimental method for calculating two coefficients of restitution of a multi-dimensional rigid body taking rotation into consideration as claimed in claim 6, characterized in that: The velocity of the collision point is calculated based on the velocity of the center of mass of the rigid body. The formula is: v A =v O +ω×r OA Among them, v O is the velocity of the center of mass, r OA is the radius vector from the center of mass to the collision contact point, and ω is the angular velocity of the rigid body rotation.

8. An experimental method for calculating two collision recovery coefficients of a multi-dimensional rigid body as claimed in claim 6, characterized in that: You can also calculate the Possion recovery coefficient. The specific steps are as follows: S1: Assemble the rigid body collision test platform, clamp the rigid body to be tested to the second fixture on the top of the frame, and adjust its position and posture; S2: Adjust the position of the high-speed camera so that it can capture the complete picture of the rigid body colliding with the inclined support bar, adjust the camera frame rate, and start the video recording process when the rigid body is released from the second fixture; S3: Import the video from the high-speed camera into the software tracker, track the center of mass position, velocity and acceleration of the rigid body through the tracker software and output the results; S4: When the rigid body performs two-dimensional motion, the maximum impact force during the collision is detected by the pressure sensor, which is used as the force at the end of the compression phase and the initial time of the recovery phase. The high-speed camera determines the starting time of the collision compression phase and the recovery phase. The force corresponding to the intermediate moments is solved by the interpolation method. Finally, the impulse ratio of the collision recovery phase and the collision compression phase is calculated to solve the Possion recovery coefficient.

9. An experimental method for calculating two collision recovery coefficients of a multi-dimensional rigid body as claimed in claim 8, characterized in that: The calculation formula of Possion recovery coefficient is: Where F is the contact force, t c is the compression end time, t e is the end time of the entire collision process, t s The collision behavior start time.

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