Leaf spring based translational stiffness simulation platform

Abstract

This invention relates to the field of space mechanics simulation technology, specifically to a translational stiffness simulation platform based on leaf springs. The platform includes a translational input end, a platform support frame, a translational transmission mechanism, and a translational stiffness-changing mechanism. The translational input end, the translational transmission mechanism, and the translational stiffness-changing mechanism are respectively fixed to the platform support frame. The translational input end is connected to the translational transmission mechanism, and the translational transmission mechanism is connected to the translational stiffness-changing mechanism. The translational input is transmitted to the translational transmission mechanism. The translational stiffness-changing mechanism adjusts the stiffness of the translational transmission mechanism by changing the stiffness of the leaf springs, thereby adjusting the translational stiffness of the translational input end. The simulation platform provided by this invention can simulate the stiffness change of a single translational degree of freedom of the upper arm during the movement of the upper and lower arms of a space station during assembly on the ground, and react on the lower arm, thus laying the foundation for studying the disturbance motion laws occurring within the combined arm under the combined movement of the upper and lower arms of a space station.

Description

Technical Field

[0001] This invention relates to the field of space mechanics simulation technology, specifically providing a translational stiffness simulation platform based on leaf springs. Background Technology

[0002] With the completion of China's space station, increasingly diverse and complex space missions need to be accomplished. The robotic arms on the space station play an increasingly important role in various operational tasks, from assisting astronauts with extravehicular activities to performing delicate operations such as carrying, transferring, and inserting / removing various payloads. These tasks require the robotic arms to meet various dynamic performance requirements.

[0003] The robotic arm system on the space station consists of two parts: a large arm and a small arm. They can work independently or combine to expand the workspace, addressing needs that require not only range transfer but also precise localized operations, significantly improving the mobility of the space robotic arm system. For dynamic performance studies of the combined arm on Earth, the large arm, serving as the base, can generally be considered equivalent to a flexible base, greatly reducing the complexity of the experimental system.

[0004] Currently designed flexible bases have variable translational stiffness, but not real-time variable stiffness. They can only pre-adjust the base to match the translational stiffness of a certain configuration of the upper arm, and then the forearm moves under this set of base stiffness characteristics. That is, they simulate a system scenario in which the upper arm remains fixed in a certain configuration while the forearm moves. They cannot realize that the translational stiffness of the flexible base changes in real time under human control during the movement of the forearm. In other words, they cannot simulate a system scenario in which the upper arm moves while the forearm moves.

[0005] Therefore, there is an urgent need for a translational stiffness simulation platform that can simulate the real-time changes in translational stiffness. Summary of the Invention

[0006] To address the aforementioned problems, this invention provides a translational stiffness simulation platform based on leaf springs, which can simulate the simultaneous movement of the large and small arms of a space station. The large arm serves as the base for the small arm, and the change in stiffness of a single translational degree of freedom caused by the configuration change during its movement allows for the study of the disturbance motion law occurring within the combined arm under the joint movement of the large and small arms of the space station.

[0007] The translational stiffness simulation platform based on leaf springs provided by this invention includes a platform support frame and a translational input end, a translational transmission mechanism, and a translational variable stiffness mechanism, all fixed to the platform support frame. The platform support frame includes a connecting platform, an upper platform, and a lower platform, with the upper and lower platforms connected by a profile support. The connecting platform is located above the upper platform, and the translational input end is fixed to the upper surface of the connecting platform. The translational transmission mechanism includes a translational guide rail assembly, a transmission shaft, a sliding component, a guide shaft, a guide slider, and a support spring. The bearing component of the translational guide rail assembly is fixed to the upper surface of the upper platform, and the moving component of the translational guide rail assembly is fixedly connected to the lower surface of the connecting platform. The sliding assembly includes a connecting slider, a translational slider, and a translational slide rail. The translational slide rail and the translational guide rail assembly are arranged parallel to each other. There are two translational sliders, distributed on both sides of the connecting slider. Both translational sliders and the connecting slider slide linearly on the translational slide rail. One end of the drive shaft is fixedly connected to the connecting slider, and the other end of the drive shaft is fixedly connected to the connecting platform. One end of the guide shaft is fixedly connected to the lower platform, and the other end of the guide shaft is fixedly connected to the bottom of the translational slide rail. The guide slider is fitted onto the guide shaft and slides up and down along the guide shaft. A support spring is fitted onto the guide shaft, with one end of the support spring abutting against the bottom of the guide slider and the other end of the support spring abutting against the lower platform. The translational variable stiffness mechanism includes a stiffening cylinder, two linkage blocks rotatably connected to the profile, two pressing blocks symmetrically arranged along the guide slider, two linear bearing assemblies, two leaf springs, two first connecting rods, two second connecting rods, two third connecting rods, and two fourth connecting rods. The two pressing blocks slide horizontally along the two linear bearing assemblies. One end of each of the two leaf springs is fixedly connected to the two pressing blocks, and the other end of each leaf spring is fixedly connected to both sides of the guide slider. One end of each of the two first connecting rods is rotatably connected to both sides of a translational slider, and the other end of each of the two first connecting rods is rotatably connected to both sides of one end of the guide slider. One end of each of the two second connecting rods is... The two second links are rotatably connected to both sides of another translational slider. The other ends of the two second links are rotatably connected to both sides of the other end of the guide slider. One end of each of the two third links is rotatably connected to one end of each of the two push blocks. The other ends of the two third links are rotatably connected to both ends of a linkage block. One end of each of the two fourth links is rotatably connected to the other ends of each of the two push blocks. The other ends of the two fourth links are rotatably connected to both ends of another linkage block. The stiffness adjustment cylinder is fixed on the lower platform and its output end is fixedly connected to one of the push blocks. By pushing the push block with the stiffness adjustment cylinder, the bending stiffness of the two leaf springs is changed, thereby adjusting the stiffness of the translational transmission mechanism.

[0008] Preferably, the leaf spring consists of two spring steel plates with a cavity between them.

[0009] Preferably, the translational input end is a triangular connecting frame with a connecting hole for connecting to a power source.

[0010] Compared with existing technologies, the simulation platform provided by this invention can simulate the stiffness change of a single translational degree of freedom of the upper arm during the movement of the upper arm when the upper and lower arms of the space station are combined on the ground, and react on the lower arm, thereby laying the foundation for studying the disturbance motion law that occurs in the combined arm when the upper and lower arms of the space station move together. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the translational stiffness simulation platform based on leaf springs provided in an embodiment of the present invention;

[0012] Figure 2 This is a schematic diagram of the translational transmission mechanism provided in an embodiment of the present invention;

[0013] Figure 3 This is a schematic diagram of the translational variable stiffness mechanism provided in an embodiment of the present invention.

[0014] The reference numerals in the accompanying drawings include: triangular connecting frame 1, connecting hole 101, platform support frame 2, connecting platform 201, upper platform 202, lower platform 203, profile 204, translational guide rail assembly 301, transmission shaft 302, guide shaft 303, guide slider 304, support spring 305, connecting slider 306, translational slider 307, translational slide rail 308, stiffening cylinder 309, linkage block 310, pushing block 311, linear bearing assembly 312, leaf spring 313, first connecting rod 314, second connecting rod 315, third connecting rod 316, fourth connecting rod 317, bearing seat 318, upper platform 202, lower platform 203, and profile 204. Detailed Implementation

[0015] In the following description, embodiments of the invention will be described with reference to the accompanying drawings. In the description below, the same modules are denoted by the same reference numerals. Where the same reference numerals are used, their names and functions are also the same. Therefore, their detailed description will not be repeated.

[0016] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not constitute a limitation thereof.

[0017] This invention provides a translational stiffness simulation platform based on leaf springs. This platform can simulate the stiffness change at the junction of the combined arms in one translational degree of freedom when the upper arm serves as the base of the lower arm.

[0018] like Figures 1-3As shown, the translational stiffness simulation platform based on leaf springs includes a translational input end, a platform support frame, a translational transmission mechanism, and a translational stiffness variable mechanism. The translational input end, the translational transmission mechanism, and the translational stiffness variable mechanism are respectively fixed on the platform support frame. The translational input end is connected to the translational transmission mechanism, and the translational transmission mechanism is connected to the translational stiffness variable mechanism. The translational input is transmitted to the translational transmission mechanism. The translational stiffness variable mechanism adjusts the stiffness of the translational transmission mechanism by changing the stiffness of the leaf spring, thereby adjusting the translational stiffness of the translational input end.

[0019] The translation input end is a triangular connecting frame 1, and a connecting hole 101 is provided on the triangular connecting frame 1 for connecting to an external power source. The power source inputs translation to the triangular connecting frame 1 to simulate the horizontal translation of the forearm.

[0020] The platform support frame includes a connecting platform 201, an upper platform 202, and a lower platform 203 arranged sequentially from top to bottom. The upper platform 202 and the lower platform 203 are connected by a profile 204. The connecting platform 201 is located above the upper platform 202. A triangular connecting frame 1 is fixed on the upper surface of the connecting platform 201. The triangular connecting frame 1 drives the connecting platform 201 to move horizontally relative to the upper platform 202.

[0021] The translational transmission mechanism includes a translational guide rail assembly 301, a transmission shaft 302, a guide shaft 303, a guide slider 304, a support spring 305, and a sliding assembly. The bearing component of the translational guide rail assembly 301 is fixed to the upper surface of the upper platform 202. The moving component of the translational guide rail assembly 301 is fixedly connected to the bottom surface of the connecting platform 201. The connecting platform 201 slides linearly along the translational guide rail assembly 301 under the drive of the triangular connecting frame 1. The sliding assembly includes a connecting slider 306, a translational slider 307, and a translational slide rail 308. The translational slide rail 308 is fixed on the upper platform 202 and is arranged parallel to the translational guide rail assembly 301. There are two translational sliders 307, which are distributed on both sides of the connecting slider 306. The two translational sliders 307 and the connecting slider 306 form a slider assembly. 08. The slide is linear; one end of the drive shaft 302 is fixed to the connecting slider 306, and the other end of the drive shaft 302 is fixed to the connecting platform 201. The lower end of the guide shaft 303 is fixedly connected to the lower platform 203, and the upper end of the guide shaft 303 is fixedly connected to the bottom of the upper platform 202. A screw passes down through the translation slide rail 308 and the upper platform 202 and connects to the upper end of the guide shaft 303 to achieve a fixed connection between the three. The guide slider 304 is fitted on the guide shaft 303 and slides up and down along the guide shaft 303. The support spring 305 is fitted on the guide shaft 303. One end of the support spring 305 abuts against the bottom of the guide slider 304, and the other end of the support spring 305 abuts against the lower platform 203. The support spring 305 provides a force to the guide slider 304 in the opposite direction of its movement.

[0022] The translational variable stiffness mechanism includes a stiffness-adjusting cylinder 309, two linkage blocks 310 rotatably connected to the profile 204, two pressing blocks 311 symmetrically arranged along the guide slider 304, two linear bearing assemblies 312, two leaf springs 313, two first connecting rods 314, two second connecting rods 315, two third connecting rods 316, and two fourth connecting rods 317. Bearing seats 318 are respectively installed on the profile 204 and the linkage blocks 310, and a bearing is installed between the two bearing seats 318 to realize the rotation of the linkage blocks 310 relative to the profile 204. The two pressing blocks 311 slide horizontally along the two linear bearing assemblies 312. One end of each of the two leaf springs 313 is fixedly connected to the two pressing blocks 311, and the other end of each leaf spring 313 is fixedly connected to both sides of the guide slider 304. One end of each of the two first connecting rods 314 is fixedly connected to the guide slider 304. A translational slider 307 is rotatably connected to both sides. The other ends of two first connecting rods 314 are rotatably connected to both sides of one end of a guide slider 304. One end of two second connecting rods 315 is rotatably connected to both sides of another translational slider 307. The other ends of two second connecting rods 315 are rotatably connected to both sides of the other end of a guide slider 304. One end of two third connecting rods 316 is rotatably connected to one end of two push blocks 311. The other ends of two third connecting rods 316 are rotatably connected to both ends of a linkage block 310. One end of two fourth connecting rods 317 is rotatably connected to the other ends of two push blocks 311. The other ends of two fourth connecting rods 317 are rotatably connected to both ends of another linkage block 310. The output end of the adjusting cylinder 309 is fixedly connected to one of the push blocks 311.

[0023] The translational motion of the translational input end in the direction of the translational guide rail assembly 301 is transmitted to the sliding assembly via the connecting platform 201 and the transmission shaft 302, causing the slider assembly to move linearly along the translational slide rail 308. This linear motion is then converted into the vertical linear motion of the guide slider 304 via the first connecting rod 314 and the second connecting rod 315. The motion of the guide slider 304 is affected by the leaf spring 313 and the support spring 305. The leaf spring 313 consists of two symmetrically stacked spring steel plates, forming a cavity between them. The stiffness of the leaf spring 313 is related to the width of the cavity; the wider the cavity, the greater the bending stiffness of the leaf spring 313 and the stronger its resistance to deformation. Therefore, by changing the width of the cavity, the output stiffness of the translational variable stiffness mechanism can be changed, thereby adjusting the stiffness of the translational transmission mechanism and achieving adjustment of the translational stiffness of the translational input end.

[0024] The stiffening cylinder 309 drives the pressing block 311 to slide on the linear bearing assembly 312. Through two linkage blocks 310 and the third connecting rod 316 and fourth connecting rod 317 on both sides of the two linkage blocks 310, the pressing block 311 on the other side moves synchronously. The movement of the pressing block 311 compresses the leaf spring 313, thereby changing the width of the cavity of the leaf spring 313. By changing the width of the cavity of the leaf spring 313 in real time, the stiffness of the slider assembly in the direction of movement is controllable and time-varying.

[0025] This invention transmits translational motion through a translational input end. A translational transmission mechanism then transmits and converts this translational motion to a translational variable stiffness mechanism. Due to interference from the translational variable stiffness mechanism, the stiffness of the translational transmission mechanism is adjusted in real time along its translational degrees of freedom by changing the stiffness of the mechanism in real time. Finally, stiffness conversion controls the stiffness at the translational input end. This method simulates the real-time changing translational stiffness of the boom during its movement.

[0026] Although embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

[0027] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A translational stiffness simulation platform based on leaf springs, characterized in that, It includes a platform support frame and a translational input end, a translational transmission mechanism, and a translational variable stiffness mechanism, all fixed to the platform support frame; wherein, The platform support frame includes a connecting platform, an upper platform, and a lower platform. The upper platform and the lower platform are connected by a profile support. The connecting platform is located above the upper platform, and the translation input end is fixed to the upper surface of the connecting platform. The translational transmission mechanism includes a translational guide rail assembly, a drive shaft, a sliding assembly, a guide shaft, a guide slider, and a support spring. The guide component of the translational guide rail assembly is fixed to the upper surface of the upper platform, and the moving component of the translational guide rail assembly is fixedly connected to the lower surface of the connecting platform. The sliding assembly includes a connecting slider, a translational slider, and a translational slide rail. The translational slide rail is arranged parallel to the translational guide rail assembly. There are two translational sliders distributed on both sides of the connecting slider, and both translational sliders and the connecting slider slide linearly on the translational slide rail. One end of the drive shaft is fixedly connected to the connecting slider, and the other end is fixedly connected to the connecting platform. One end of the guide shaft is fixedly connected to the lower platform, and the other end is fixedly connected to the bottom of the translational slide rail. The guide slider is mounted on the guide shaft and slides up and down along the guide shaft. The support spring is mounted on the guide shaft, with one end abutting against the bottom of the guide slider and the other end abutting against the lower platform. The translational variable stiffness mechanism includes a stiffness-adjusting cylinder, two linkage blocks rotatably connected to the profile, two pressing blocks symmetrically arranged along the guide slider, two linear bearing assemblies, two leaf springs, two first connecting rods, two second connecting rods, two third connecting rods, and two fourth connecting rods. The two pressing blocks slide horizontally along the two linear bearing assemblies. One end of each of the two leaf springs is fixedly connected to the two pressing blocks, and the other end of each leaf spring is fixedly connected to both sides of the guide slider. One end of each of the two first connecting rods is rotatably connected to both sides of a translational slider, and the other end of each of the two first connecting rods is rotatably connected to both sides of one end of the guide slider. One end of each of the two second connecting rods is rotatably connected to... The two sides of another translational slider are rotatably connected, the other ends of the two second connecting rods are rotatably connected to the two sides of the other end of the guide slider, one end of the two third connecting rods is rotatably connected to one end of the two push blocks, the other end of the two third connecting rods is rotatably connected to both ends of a linkage block, one end of the two fourth connecting rods is rotatably connected to the other end of the two push blocks, and the other end of the two fourth connecting rods is rotatably connected to both ends of another linkage block. The stiffness-adjusting cylinder is fixed on the lower platform and its output end is fixedly connected to one of the push blocks. The stiffness-adjusting cylinder pushes the push block to change the bending stiffness of the two leaf springs, thereby adjusting the stiffness of the translational transmission mechanism.

2. The translational stiffness simulation platform based on leaf springs according to claim 1, characterized in that, The leaf spring is composed of two spring steel plates with a cavity between them.

3. The translational stiffness simulation platform based on leaf springs according to claim 1, characterized in that, The translational input end is a triangular connecting frame with a connection hole for connecting to a power source.

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