CN117944093A

CN117944093A - Active rigidity-variable modularized base

Info

Publication number: CN117944093A
Application number: CN202410343282.9A
Authority: CN
Inventors: 胡金鑫; 吴清文; 于鹏; 满罡
Original assignee: Changchun Institute of Optics Fine Mechanics and Physics of CAS
Current assignee: Changchun Institute of Optics Fine Mechanics and Physics of CAS
Priority date: 2024-03-25
Filing date: 2024-03-25
Publication date: 2024-04-30

Abstract

The invention relates to the technical field of space mechanics simulation, in particular to an active rigidity-changing modularized base, which comprises a base input end, a rotation rigidity simulation platform and a translation rigidity simulation platform, wherein the base input end is used for inputting rotation or translation in the horizontal direction, the rotation rigidity simulation platform is used for simulating the change of rotation rigidity, and the translation rigidity simulation platform is used for simulating the change of translation rigidity. The flexible base provided by the invention can simulate the rigidity change of the big arm in the movement process when the big arm and the small arm of the space station are combined on the ground and react to the small arm, thereby laying a foundation for researching the disturbance movement law generated in the combined arm under the joint movement of the big arm and the small arm of the space station.

Description

Active rigidity-variable modularized base

Technical Field

The invention relates to the technical field of space mechanics simulation, and particularly provides an active rigidity-variable modularized base.

Background

As the chinese space station is fully built, increasingly diverse, complex space tasks need to be completed. The mechanical arm on the space station has wider roles in various operation tasks, from assisting the operation of the spaceship outside the cabin to carrying, transferring, plugging and pulling various loads and other fine operations. These tasks all require the robotic arm to meet various dynamic performance requirements.

The mechanical arm system on the space station consists of a big arm and a small arm. The two can work independently, and can also form a combined arm to further expand a working space so as to meet the working requirements of local fine operation and not only need range transfer, but also greatly improve the maneuverability of the space manipulator system. Aiming at the research on the dynamic performance of the combined arm on the ground, the large arm serving as the base can be generally equivalent to a flexible base, so that the complexity of a test system is greatly reduced.

The presently discovered flexible bases of prior designs are variable stiffness, but not time-varying stiffness. The stiffness of the base can only be adjusted in advance to meet the stiffness of the large arm under a certain configuration, and then the small arm moves under the stiffness characteristic of the base, namely the base is simulated as follows: the big arm maintains a certain configuration stationary and the system scene of the movement of the small arm, and the rigidity of the base is also changed in real time by manual control in the movement process of the small arm, namely the system scene that the small arm moves and the big arm moves at the same time cannot be simulated.

Disclosure of Invention

The invention provides the active rigidity-changing modularized base, which can simulate the simultaneous movement of the large arm and the small arm of the space station, and the large arm is used as the base of the small arm, so that the rigidity change caused by the configuration change in the movement process of the large arm and the small arm of the space station is researched, and the disturbance movement rule generated in the combined arm under the common movement of the large arm and the small arm of the space station is researched.

The invention provides an active rigidity-variable modularized base which comprises a base input end, a rotation rigidity simulation platform and a translation rigidity simulation platform; the rotation stiffness simulation platform comprises a rotation platform support frame, a motion conversion mechanism and a rotation stiffness variation mechanism, wherein the rotation stiffness variation mechanism is arranged on the rotation platform support frame, the base input end and the rotation stiffness variation mechanism are respectively connected with the motion conversion mechanism, the motion conversion mechanism is used for converting rotation of the base input end into translation, and the rotation stiffness variation mechanism is used for adjusting self stiffness in a mode of changing the effective number of turns of a spring and acts on the motion conversion mechanism to realize adjustment of rotation stiffness of the base input end; the translational rigidity simulation platform comprises a first transmission shaft, a first platform supporting plate, a first guide rail group and a first translational rigidity-changing mechanism, wherein a guide bearing piece of the first guide rail group is arranged on the first platform supporting plate, a moving piece of the first guide rail group is fixedly connected with the bottom of a rotating platform supporting frame, the first translational rigidity-changing mechanism is connected with the rotating platform supporting frame through the first transmission shaft, and the first translational rigidity-changing mechanism is used for adjusting self rigidity in a moment-changing mode to realize adjustment of translational rigidity of an input end of a base; or the translational rigidity simulation platform comprises a translational platform support frame, a translational transmission mechanism and a second translational rigidity-changing mechanism, wherein the translational transmission mechanism is fixedly connected with the rotational platform support frame, the translational movement input by the input end of the base is transmitted to the translational transmission mechanism, and the second translational rigidity-changing mechanism is fixed on the platform support frame and connected with the translational transmission mechanism and is used for adjusting the rigidity of the translational transmission mechanism in a mode of changing the rigidity of the leaf spring so as to realize the adjustment of the translational rigidity of the input end of the base; or the translational rigidity simulation platform comprises a third transmission shaft, a second platform supporting plate, a second guide rail group and a third translational rigidity-changing mechanism, wherein a guide bearing piece of the second guide rail group is arranged on the second platform supporting plate, a moving piece of the second guide rail group is fixedly connected with the bottom of the rotating platform supporting frame, the third translational rigidity-changing mechanism is connected with the rotating platform supporting frame through the third transmission shaft, and the third translational rigidity-changing mechanism is used for adjusting the self rigidity in a pretightening force changing mode to realize the adjustment of the translational rigidity of the input end of the base.

Preferably, the rotary variable stiffness mechanism comprises a top cone seat and two rotary variable stiffness adjusting units, and the two rotary variable stiffness adjusting units are respectively propped to two sides of the top cone seat through top cones; the two rotation rigidity-changing adjusting units comprise a rotation rigidity-adjusting motor, a first coupler, ball splines, a rotating shaft, springs, a pedestal, clamping pieces, bearings, shaft sleeves and end covers, wherein the rotation rigidity-adjusting motor is fixed on a support frame of a rotation platform; the pedestal comprises a T-shaped base and a sleeve, the T-shaped base is mounted on a rotary platform supporting frame and is fixedly connected with the sleeve, the sleeve is sleeved on the outer side of the spring, the clamping piece is fixedly connected with the sleeve and is clamped into the spring, the rotation of an output shaft of the rotation rigidity adjusting motor is controlled, the rotation is sequentially transmitted to the spring through a first coupler, a ball spline, a rotating shaft and a shaft sleeve, the spring is abutted against the clamping piece to rotate along the radial direction, the effective number of turns is changed, and the time-varying rigidity output of the end cover to the tip cone seat is realized.

Preferably, the clamping piece is a limit bolt, an adjusting hole for adjusting the position of the limit bolt is formed in the sleeve, the head of the limit bolt is clamped at the outer side of the adjusting hole, and a screw rod of the limit bolt passes through the adjusting hole downwards and then is clamped into the spring.

Preferably, the clamping piece comprises a clamping cone and a clamping cone block which are of an integrated structure or a split structure, the clamping cone block is fixed on the sleeve through a fastening bolt, waist-shaped holes for the fastening bolt to adjust positions are respectively formed in the clamping cone block and the sleeve, the sleeve is further provided with an avoidance hole, and the clamping cone downwards penetrates through the avoidance hole and then is clamped into the spring.

Preferably, the motion conversion mechanism comprises a second coupling, a sector gear and a sliding assembly; one end of the second coupler is fixedly connected with the input end of the base through a rotating shaft, the other end of the second coupler is fixedly connected with the sector gear through the rotating shaft, the sliding assembly comprises a sliding block and a sliding rail which are in sliding fit, a rack is machined on one side of the sliding block, a tip cone seat is fixedly mounted on the sliding block, rotation of the input end of the base is transmitted to the sector gear through the second coupler, and the rotation of the input end of the base is converted into translation of the sliding block on the sliding rail through meshing of the sector gear and the rack.

Preferably, the rotary platform support frame comprises a platform bottom plate and a platform top plate which are connected through sectional materials, and the T-shaped base, the sliding rail and the rotary rigidity adjusting motor are fixedly arranged on the platform bottom plate.

Preferably, the input end of the base comprises a triangular connecting frame and a U-shaped frame which are connected in a rotating way, and the triangular connecting frame is provided with a connecting hole for connecting with a power source; the two ends of the U-shaped frame are outwards provided with table edges which are fixed on the top plate of the platform through screws.

Preferably, the T-shaped base is fixedly arranged on the platform bottom plate through two L-shaped connecting blocks, and a gap between the two L-shaped connecting blocks enables the sliding rail to pass through.

Preferably, the rotary rigidity-adjusting motor is fixedly arranged on the platform bottom plate through a motor bracket.

Preferably, the first translational rigidity-changing mechanism comprises a sliding component and two translational rigidity-changing adjusting units which are symmetrically arranged by taking the sliding component as a center, the two translational rigidity-changing adjusting units are respectively in close contact with the sliding component, and the translational rigidity of the input end of the base is adjusted in real time by the sliding component.

Preferably, the translational rigidity-changing adjusting unit comprises a circular arc track, a track rotation center column, an inscription sliding block, a guiding connecting arm, a guiding connecting rod, a pressure spring, a first translational rigidity-adjusting motor, a rigidity-adjusting rotation center column, a bevel gear and a linear bearing; the track rotation center column is fixed on the platform bottom plate; one end of the arc track is tightly contacted with the sliding component, and the other end of the arc track is fixedly connected with the track rotation center column, so that the sliding component extrudes the arc track, and the arc track rotates around the track rotation center column; the rigidity-adjusting rotary center column and the first translational rigidity-adjusting motor are arranged on the platform bottom plate, the bevel gear is arranged on the rigidity-adjusting rotary center column, and the output end of the first translational rigidity-adjusting motor is meshed with the bevel gear, so that the first translational rigidity-adjusting motor drives the output end of the rigidity-adjusting rotary center column to rotate through the bevel gear; the fixed end of the guide connecting arm is fixedly connected with the output end of the rigid adjusting rotation center column, and the movable end of the guide connecting arm is provided with a mounting piece for mounting the guide connecting rod; one end of the linear bearing is fixed on the guide connecting arm, and the other end of the linear bearing is connected with the guide connecting rod, so that the guide connecting rod can be subjected to telescopic adjustment along the linear bearing; the installation side of the internal connecting sliding block is arranged on the guide connecting rod; the movable side of the inscription slide block is matched with the inner wall of the circular arc track, so that the inscription slide block drives the guide connecting rod to move along the inner wall of the circular arc track; one end of the pressure spring is fixed on the fixed end of the guide connecting arm, and the other end of the pressure spring is connected with the guide connecting rod, so that the first translational rigidity adjusting motor can control the rigidity adjusting rotary center column in real time, adjust the moment of the pressure spring and be matched with the expansion and contraction of the pressure spring, and further realize the real-time adjustment of the translational rigidity of the sliding component to the input end of the base.

Preferably, the sliding assembly comprises a sliding block and a linear sliding rail which are in sliding fit, the linear sliding rail is fixed on the platform bottom plate, the first transmission shaft is fixed on the sliding block, a roller is sleeved on the first transmission shaft, one end of the circular arc rail is in close contact with the roller, and when the first transmission shaft drives the sliding block to translate on the linear sliding rail, the roller rolls and extrudes the circular arc rail, so that the circular arc rail rotates around the rail revolution center column.

Preferably, the translation transmission mechanism comprises a translation guide rail group, a second transmission shaft, a smoothing component, a guide shaft, a guide sliding block and a support spring; the guide bearing piece of the translation guide rail group is fixed on the translation platform support frame, and the moving piece of the translation guide rail group is fixedly connected with the platform bottom plate; the smooth component comprises a connecting slide block, a translational slide block and a translational slide rail, the translational slide rail and the translational guide rail group are arranged in parallel, the number of the translational slide blocks is two and distributed on two sides of the connecting slide block, and the two translational slide blocks and the connecting slide block linearly slide on the translational slide rail; one end of the second transmission shaft is fixedly connected with the connecting sliding block, the other end of the second transmission shaft is fixedly connected with the platform bottom plate, one end of the guide shaft is fixedly connected with the translational platform support frame, the other end of the guide shaft is fixedly connected with the bottom of the translational sliding rail, the guide sliding block is sleeved on the guide shaft and slides up and down along the guide shaft, the supporting spring is sleeved on the guide shaft, one end of the supporting spring is abutted to the bottom of the guide sliding block, and the other end of the supporting spring is abutted to the translational platform support frame.

Preferably, the second translational rigidity-changing mechanism comprises a rigidity-adjusting cylinder, two linkage blocks rotationally connected with the translational platform support frame, and two pushing blocks, two linear bearing groups, two leaf springs, two first connecting rods, two second connecting rods, two third connecting rods and two fourth connecting rods which are symmetrically arranged along the guide sliding block, wherein the two pushing blocks horizontally slide along the two linear bearing groups, one ends of the two leaf springs are respectively fixedly connected with the two pushing blocks, the other ends of the two leaf springs are respectively fixedly connected with two sides of the guide sliding block, one ends of the two first connecting rods are respectively rotationally connected with two sides of one translational sliding block, the other ends of the two first connecting rods are respectively rotationally connected with two sides of one end of the guide sliding block, one ends of the two second connecting rods are respectively rotationally connected with two sides of the other end of the guide sliding block, the other ends of the two third connecting rods are respectively rotationally connected with two ends of one pushing block, one ends of the two fourth connecting rods are respectively rotationally connected with two ends of the two bending blocks, one end of the two fourth connecting rods is respectively rotationally connected with two ends of the two translational rigidity-adjusting blocks, and the rigidity-adjusting mechanism is fixedly connected with two ends of the other translational rigidity-adjusting cylinder.

Preferably, the leaf spring is formed of two spring steel sheets with a cavity therebetween.

Preferably, the translational platform support frame comprises an upper platform and a lower platform, the upper platform is connected with the lower platform through a section bar support, a bearing guide piece of the translational guide rail group is fixed on the surface of the upper platform, and the guide shaft, the rigidity adjusting cylinder and the two linear bearing groups are fixed on the surface of the lower platform, and the linkage block is rotationally connected with the section bar.

Preferably, the third translational rigidity-changing mechanism comprises a rigidity-adjusting sliding block, a rigidity-adjusting guide rail, a spring steel wire rope, a fixed wheel, a guide wheel, a rope pressing wheel, a translational rope collecting wheel, a worm wheel, a bearing seat and a second translational rigidity-adjusting motor; the steel adjusting guide rail is fixedly connected to the second platform supporting plate and parallel to the second guide rail group, the steel adjusting sliding block linearly slides on the steel adjusting guide rail, and two ends of the third transmission shaft are fixedly connected with the steel adjusting sliding block and the platform bottom plate respectively; the fixed wheels and the translational rope collecting wheels are positioned at one end of the rigidity adjusting guide rail, and the number of the rope pressing wheels is not less than two and is fixed at two ends of the rigidity adjusting slide block; the guide wheel is positioned at the other end of the rigid adjusting guide rail; one end of the spring wire rope is fixed on the fixed wheel, and the other end of the spring wire rope is fixed on the translational rope collecting wheel after passing through one rope pressing wheel, the guide wheel and the other rope pressing wheel in sequence; the second translational rigidity adjusting motor and the bearing seat are respectively fixed on the second platform supporting plate, the output end of the second translational rigidity adjusting motor is connected with one end of the worm through a third coupler, the bearing seat at the other end of the worm is rotationally connected, the worm wheel is sleeved on the translational rigidity collecting wheel and meshed with the worm, the rotation output by the second translational rigidity adjusting motor is transmitted to the translational rigidity collecting wheel through the matching of the worm and the worm wheel, and the pre-tightening force of the rigidity adjusting sliding block along the rigidity adjusting guide rail is controlled through a spring steel wire rope, so that the translational rigidity of the input end of the base is adjusted.

Preferably, a reversing wheel for changing the direction of the spring wire rope is arranged between the fixed wheel and the rope pressing wheel, between the rope pressing wheel and the guide wheel and between the rope pressing wheel and the translational rope collecting wheel.

Preferably, the number of the translational rigidity simulation platforms is at least two, the translational rigidity simulation platforms are distributed up and down and are connected with each other, and the movement directions of the first guide rail group or the second guide rail group or the translational guide rail group of each translational rigidity simulation platform are different.

Preferably, the number of the translational rigidity simulation platforms is two, and the movement directions of the first guide rail group or the second guide rail group or the translational guide rail group of the two translational rigidity simulation platforms are vertical.

Compared with the prior art, the flexible base provided by the invention can simulate the rigidity change of the large arm in the movement process when the large arm and the small arm of the space station are combined on the ground and react to the small arm, so that a foundation is laid for researching the disturbance movement law generated in the combined arm under the joint movement of the large arm and the small arm of the space station.

Drawings

Fig. 1 is an overall structural diagram of an active variable stiffness modular base provided according to embodiment 1 of the present invention.

Fig. 2 is a partial block diagram of a rotational stiffness simulation platform provided according to embodiment 1 of the present invention.

Fig. 3 is an overall structural view of a rotational variable stiffness adjustment unit provided according to embodiment 1 of the present invention.

Fig. 4 is a sectional structural view of a rotational variable stiffness adjustment unit provided according to embodiment 1 of the present invention.

Fig. 5 is a structural diagram of a translational stiffness simulation platform provided in accordance with embodiment 1 of the present invention.

Fig. 6 is a structural diagram of a translational rigidity-varying mechanism provided in embodiment 1 of the present invention.

Fig. 7 is a top view of a translational stiffness varying mechanism provided in accordance with embodiment 1 of the present invention.

Fig. 8 is a schematic diagram of a translational rigidity changing mechanism provided in embodiment 1 of the present invention.

Fig. 9 is an overall structural diagram of an active variable stiffness modular base provided according to embodiment 2 of the present invention.

Fig. 10 is a structural diagram of a translational stiffness simulation platform provided according to embodiment 2 of the present invention.

Fig. 11 is a matching diagram of a first view angle of a translational motion transmission mechanism and a translational motion rigidity-varying mechanism according to embodiment 2 of the present invention;

fig. 12 is a diagram showing the combination of a translational motion transmission mechanism and a translational motion stiffness varying mechanism according to embodiment 2 of the present invention at a second view angle;

Fig. 13 is a structural diagram of a translational rigidity changing mechanism provided in embodiment 2 of the present invention.

Fig. 14 is an overall structural diagram of an active variable stiffness modular base provided in accordance with embodiment 3 of the present invention.

FIG. 15 is an overall block diagram of a translational stiffness simulation platform provided in accordance with embodiment 3 of the present invention;

fig. 16 is a schematic diagram of a translational rigidity changing mechanism provided in accordance with embodiment 3 of the present invention.

Reference numerals of embodiment 1 include: base input end 1, triangle connecting frame 11, connecting hole 111, U-shaped frame 12, table edge 121, rotational stiffness simulation platform 2, rotational platform support frame 21, platform bottom plate 211, platform top plate 212, profile 213, motion conversion mechanism 22, second coupling 221, sector gear 222, sliding assembly 223, sliding rail 2231, sliding block 2232, rotational stiffness changing mechanism 23, top cone seat 231, rotational stiffness changing adjusting unit 232, top cone 233, rotational stiffness adjusting motor 2321, first coupling 2322, ball spline 2323, rotation shaft 2324, spring 2325, pedestal 2326, T-shaped base 23261, sleeve 23262, clamping piece 2327, clamping cone 23271, clamping cone block 23272, fastening bolt 23273, bearing 2328, and bearing 2328 the device comprises a shaft sleeve 2329, an end cover 2330, a motor bracket 2331, an L-shaped connecting block 2332, a first translational rigidity simulation platform 3, a transmission shaft 31, a platform supporting plate 32, a guide rail group 33, a translational rigidity changing mechanism 34, a sliding component 341, a sliding block 3411, a linear sliding rail 3412, a translational rigidity changing adjusting unit 342, a circular arc track 3421, a track rotation center column 3422, an inscribed sliding block 3423, a guide connecting arm 3424, a guide connecting rod 3425, a pressure spring 3426, a translational rigidity adjusting motor 3427, a rigidity adjusting rotation center column 3428, a drive bevel gear 3429, a linear bearing 3430, a roller 3431, a driven bevel gear 3432, a second translational rigidity simulation platform 4, a platform supporting plate 41, a guide rail group 42 and a translational rigidity changing mechanism 43.

Reference numerals of embodiment 2 include: the base input end 1 ', the rotational stiffness simulation platform 2', the first translational stiffness simulation platform 3', the translational guide rail set 301, the transmission shaft 302, the guide shaft 303, the guide slide block 304, the support spring 305, the connecting slide block 306, the translational slide block 307, the translational slide rail 308, the rigidity adjusting cylinder 309, the linkage block 310, the pushing block 311, the linear bearing set 312, the leaf spring 313, the first connecting rod 314, the second connecting rod 315, the third connecting rod 316, the fourth connecting rod 317, the bearing seat 318, the upper platform 319, the lower platform 320, the profile 321, the second translational stiffness simulation platform 4', the transmission shaft 401, the translational guide rail set 402 and the upper platform 403.

Reference numerals of embodiment 3 include: the mechanical rigidity simulation platform comprises a base input end 1 ', a rotation rigidity simulation platform 2', a first translational rigidity simulation platform 3', a transmission shaft 3-1, a platform supporting plate 3-2, a guide rail group 3-3, a translational rigidity changing mechanism 3-4, a rigidity adjusting sliding block 3-4-1, a rigidity adjusting guide rail 3-4-2, a spring steel wire rope 3-4-3, a fixed wheel 3-4-4, a guide wheel 3-4-5, a rope pressing wheel 3-4-6, a translational rope collecting wheel 3-4-7, a worm 3-4-8, a worm wheel 3-4-9, a bearing seat 3-4-10, a translational rigidity adjusting motor 3-4-11, a reversing wheel 3-4-12, a second translational rigidity simulation platform 4', a platform supporting plate 4-1 and a guide rail group 4-2.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, like modules are denoted by like reference numerals. In the case of the same reference numerals, their names and functions are also the same. Therefore, a detailed description thereof will not be repeated.

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be further described in detail with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not to be construed as limiting the invention.

The invention provides three active variable-rigidity modularized bases with different structural designs, wherein each modularized base can simulate rigidity change of a combined arm in multiple degrees of freedom when a large arm is used as a forearm base.

The following description will be given by taking three degrees of freedom as an example, and the same applies to other degrees of freedom. The three degrees of freedom are a horizontal rotation degree of freedom and two translation degrees of freedom perpendicular to the movement direction respectively, so that the modularized base can simulate the change of rotation rigidity of horizontal rotation and the change of two perpendicular translation rigidity.

The three active rigidity-changing modularized bases adopt base input ends and rotation rigidity simulation platforms with the same structural design, and translational rigidity simulation platforms with different structural designs, and the specific structures of the three active rigidity-changing modularized bases are described in detail in three embodiments below.

Example 1

As shown in fig. 1 to 8, the active variable stiffness modular base provided in embodiment 1 of the present invention includes a base input end 1, a rotational stiffness simulation platform 2, a first translational stiffness simulation platform 3, and a second translational stiffness simulation platform 4; the rotational stiffness simulation platform 2 comprises a rotational platform support frame 21, a motion conversion mechanism 22 and a rotational stiffness variation mechanism 23, wherein the rotational platform support frame 21 comprises a platform bottom plate 211 and a platform top plate 212 from bottom to top, a section bar 213 is connected between the platform bottom plate 211 and the platform top plate 212, and the section bar 213 supports the platform top plate 212 on the platform bottom plate 211; the rotation rigidity-changing mechanism 23 is mounted on the platform bottom plate 211, the base input end 1 and the rotation rigidity-changing mechanism 23 are respectively connected with the motion conversion mechanism 22, the base input end 1 is used for being connected with an external power source to simulate three-direction motions of the forearm, the motions comprise horizontal rotation and horizontal orthogonal translation, the motion conversion mechanism 22 is used for converting the rotation of the base input end 1 into the translation, the rotation rigidity-changing mechanism 23 is used for adjusting the rigidity of the base input end by changing the effective number of turns of a spring and acts on the motion conversion mechanism 22 to change the rotation rigidity of the base input end 1.

The first translational rigidity simulation platform 3 comprises a transmission shaft 31, a platform supporting plate 32, a guide rail group 33 and a translational rigidity-changing mechanism 34, wherein a bearing guide piece of the guide rail group 33 is arranged on the platform supporting plate 32, a moving piece of the guide rail group 33 is fixedly connected with the bottom of the platform bottom plate 211 through an heightening frame, the translational rigidity-changing mechanism 34 is connected with the platform bottom plate 211 through the transmission shaft 31, and the translational rigidity-changing mechanism 34 is used for adjusting self rigidity in a mode of changing moment and adjusting translational rigidity of the input end 1 of the base in a horizontal direction; the structure of the second dynamic stiffness simulation platform 4 is the same as that of the first translational stiffness simulation platform 3, a transmission shaft in the second dynamic stiffness simulation platform 4 is fixedly connected with the platform supporting plate 32, a bearing and guiding piece of a guide rail group 42 in the second dynamic stiffness simulation platform 4 is fixedly connected to the platform supporting plate 41, a moving piece of the guide rail group 42 is fixedly connected with the bottom of the platform supporting plate 32, the guide rail group 42 is orthogonally arranged with the guide rail group 33, namely, the moving directions of the guide rail group and the guide rail group are perpendicular, and a translational stiffness changing mechanism 43 of the second dynamic stiffness simulation platform 4 is used for adjusting the translational stiffness of the other horizontal direction of the base input end 1.

The base input end 1 comprises a triangular connecting frame 11 and a U-shaped frame 12, wherein a connecting hole 111 is formed in the triangular connecting frame 11 and is used for being connected with an external power source, table edges 121 are formed at two ends of the U-shaped frame 12, the table edges 121 are fixed on a platform top plate 212 through bolts, and the triangular connecting frame 11 can rotate relative to the U-shaped frame 12.

The motion conversion mechanism 22 comprises a second coupler 221, a sector gear 222 and a sliding assembly 223, the sliding assembly 223 comprises a sliding rail 2231 and a sliding block 2232, the sliding rail 2231 is fixedly arranged on a platform bottom plate 211, the sliding block 2232 linearly slides on the sliding rail 2231, racks are machined on the side surfaces of the sliding block 2232 and are meshed with the sector gear 222 for transmission, two ends of the second coupler 221 are respectively connected with a rotating shaft, the rotating shaft connected with the upper end of the second coupler 221 is fixedly connected with a triangular connecting frame 11, the rotating shaft is in rotating fit with the U-shaped frame 12 through a rolling bearing, and the rotating shaft connected with the lower end of the second coupler 221 is fixedly connected with the sector gear 222, so that the rotation of the base input end 1 and the sector gear 222 is synchronized.

When the base input end 1 rotates horizontally, the second coupler 221 and the sector gear 222 are driven to rotate, and the horizontal rotation of the base input end 1 is converted into linear sliding of the slider 2232 on the sliding rail 2231 through the meshing transmission of the sector gear 222 and the rack on the slider 2232.

The rotary rigidity-changing mechanism 23 comprises a top cone seat 231 and two rotary rigidity-changing adjusting units 232 with the same structure, wherein top cone holes are respectively processed on two opposite surfaces of the top cone seat 231 and are used for installing a top cone 233, the two rotary rigidity-changing adjusting units 232 are respectively abutted to the two top cones 233, the top cone seat 231 is fixed on a sliding block 2232, the sliding block 2232 is subjected to acting forces in two directions, namely, the translational motion of the sliding block 2232 is interfered by the two rotary rigidity-changing adjusting units 232. By changing the output stiffness of the rotational stiffness varying adjustment unit 232 in real time, the rotational stiffness of the base input 1 is made controllable and time varying.

The rotary rigidity-changing adjusting unit 232 comprises a rotary rigidity-adjusting motor 2321, a first coupler 2322, a ball spline 2323, a rotary shaft 2324, a spring 2325, a pedestal 2326, a clamping piece 2327, a bearing 2328, a shaft sleeve 2329 and an end cover 2330, wherein the rotary rigidity-adjusting motor 2321 is fixed on the platform bottom plate 211 through a motor bracket 2331, an output shaft of the rotary rigidity-adjusting motor 2321 is connected with a spline shaft of the ball spline 2323 through the first coupler 2322, a flange of the ball spline 2323 is connected with the rotary shaft 2324, the shaft sleeve 2329 is sleeved at the end part of the rotary shaft 2324, the spring 2325 and the bearing 2328 are respectively sleeved at two ends of the shaft sleeve 2329, the end cover 2330 is sleeved on the shaft sleeve 2329 and is positioned at the outer side of the spring 2325 and the bearing 2328, the end cover 2330 is abutted against the top cone 233, an inner ring of the bearing 2328 is contacted with the shaft sleeve 2329, and an outer ring of the bearing 8 is contacted with the end cover 2330. The pedestal 2326 comprises a T-shaped base 23261 and a sleeve 23262 which are of an integral structure or a split structure, the T-shaped base 23261 is fixedly arranged on the platform bottom plate 211 through two L-shaped connecting blocks 2332, the sleeve 23262 is fixedly supported, the sleeve 2325 is sleeved outside the spring 2325, the two L-shaped connecting blocks 2332 are arranged at intervals, and a gap reserved in the middle is used for a sliding rail 2231 to pass through; the clamping piece 2327 comprises a clamping cone 23271 and a clamping cone block 23272 which are of an integral structure or a split structure, the clamping cone block 23272 is fixed on the outer side of the sleeve 23262 through a fastening bolt 23273, and the clamping cone 23271 passes through the sleeve 23262 and is clamped into the spring 2325; the output shaft of the rotation control rigid adjusting motor 2321 rotates and is sequentially transmitted to the spring 2325 through the first coupler 2322, the ball spline 2323, the rotating shaft 2324 and the shaft sleeve 2329, the spring 2325 is abutted against the clamping cone 23271 to rotate in the radial direction, so that the effective number of turns of the spring 2325 is changed, and the time-varying rigidity output of the end cover 2330 to the tip cone seat 231 is realized.

In order to adjust the position of the clamping cone 23271, waist-shaped holes for adjusting the position of the fastening bolt 23273 are respectively formed in the clamping cone block 23272 and the sleeve 23262, an avoidance hole is further formed in the sleeve 23262, and the clamping cone 23271 passes through the avoidance hole downwards and then is clamped into the spring 2325.

Alternatively, the clamping member 2327 may also be a limiting bolt, an adjusting hole is formed in the sleeve 23262, the head of the limiting bolt is clamped at the outer side of the adjusting hole, and a screw rod of the limiting bolt passes through the adjusting hole downwards and then is clamped into the spring 2325, and is locked on the sleeve 23262 through a nut.

The translational rigidity-changing mechanism 34 comprises a sliding component 341 and two translational rigidity-changing adjusting units 342 with the same structure, the two translational rigidity-changing adjusting units 342 are symmetrically distributed by taking the sliding component 341 as a center, the two translational rigidity-changing adjusting units 342 are respectively in close contact with the sliding component 341, and the translational rigidity of the base input end 1 is adjusted in real time by the sliding component 341 through the two translational rigidity-changing adjusting units 342.

The sliding assembly 341 includes a sliding block 3411 and a linear sliding rail 3412, the linear sliding rail 3412 is fixed on the platform supporting plate 32, the sliding block 3411 slides on the linear sliding rail 3412, and two ends of the transmission shaft 31 are fixedly connected with the sliding block 3411 and the platform bottom plate 211 respectively.

Each translational rigidity-changing adjusting unit 342 comprises an arc track 3421, a track rotation center column 3422, an inscribed sliding block 3423, a guiding connecting arm 3424, a guiding connecting rod 3425, a pressure spring 3426, a translational rigidity-adjusting motor 3427, a rigidity-adjusting rotation center column 3428, a driving bevel gear 3429, a linear bearing 3430, a roller 3431 and a driven bevel gear 3432.

The track rotation center column 3422 is fixed on the platform support plate 32, one end of the arc track 3421 is in close contact with the roller 3431 sleeved on the transmission shaft 31, and the other end of the arc track 3421 is fixedly connected with the track rotation center column 3422. When the transmission shaft 31 and the roller 3431 thereof translate along the translation sliding rail, the roller 3431 extrudes the circular arc track 3421, so that the circular arc track 3421 rotates by the track rotation center column 3422.

The rigidity-adjusting rotary center column 3428 and the translational rigidity-adjusting motor 3427 are arranged on the platform supporting plate 32, the driving bevel gear 3429 is arranged at the output end of the translational rigidity-adjusting motor 3427, the driven bevel gear 3432 is sleeved on the rigidity-adjusting rotary center column 3428 and meshed with the driving bevel gear 3429, and the translational rigidity-adjusting motor 3427 drives the output end of the rigidity-adjusting rotary center column 3428 to rotate through the meshing of the driving bevel gear 3429 and the driven bevel gear 3432.

The fixed end of the guiding connecting arm 3424 is fixedly connected with the output end of the rigid rotation center column 3428, and the movable end of the guiding connecting arm 3424 is provided with a mounting piece for mounting the guiding connecting rod 3425. The guide rod of the linear bearing 3430 is fixed to the guide link arm 3424, and the bearing of the linear bearing 3430 is connected to the guide link 3425 so that the guide link 3425 moves in the direction of the linear bearing 3430.

The installation side of the inscription slider 3423 is installed on the guide link 3425, and the movable side of the inscription slider 3423 is matched with the inner wall of the circular arc track 3421, so that the inscription slider 3423 drives the guide link 3425 to move along the inner wall of the circular arc track 3421. One end of the compression spring 3426 is fixed on the fixed end of the guide connecting arm 3424, and the other end of the compression spring 3426 is connected with the guide connecting rod 3425.

When the slider 3411 slides along the linear rail 3412, it always keeps in contact with the circular arc rail 3421. The sliding block 3411 receives a resistance force F against sliding. F simultaneously counteracts the circular arc track 3421 to enable the circular arc track 3421 to rotate around the track rotation center column 3422, and the moment is l. In this process, the resistance force F is transmitted to the compression spring 3426 via the inscribed slider 3423 and the guide link 3425. The compression spring 3426 is pressed to generate the elastic force F ₁, and the elastic moment is l ₁. Balancing the moment:

F·l=F₁·l₁；

Wherein the resistance force F is a function of the output stiffness of the translational stiffness varying mechanism 34 and the displacement amount delta thereof, and the elastic force F ₁ is a function of the stiffness of the compression spring 3426 and the displacement amount delta thereof. Therefore, the rigidity of the compression spring 3426 is constant, and the output rigidity of the translational rigidity-changing mechanism 34 can be changed by changing the elastic moment l ₁.

The elastic force moment l ₁ is changed in such a way that the translational rigidity-adjusting motor 3427 drives the driving bevel gear 3429 to be meshed with the driven bevel gear 3432 for transmission, and drives the internal connecting slide block 3423, the guide connecting rod 3425, the pressure spring 3426 and the linear bearing 3430 to rotate around the rigidity-adjusting rotation center column 3428. The stiffness of the translational stiffness varying mechanism 34 in this direction of motion is adjusted by changing the spring moment l ₁ in real time.

Example 2

As shown in fig. 9 to 13, the active stiffness-variable modularized base provided in embodiment 2 of the present invention includes a base input end 1 ', a rotational stiffness simulation platform 2', a first translational stiffness simulation platform 3 'and a second translational stiffness simulation platform 4', the structure of the base input end 1 'is the same as that of the base input end 1 of embodiment 1, and the structure of the rotational stiffness simulation platform 2' is the same as that of the rotational stiffness simulation platform 2 of embodiment 1, so that detailed structures of the base input end 1 'and the rotational stiffness simulation platform 2' are not repeated.

The first translational rigidity simulation platform 3 'comprises a translational platform support frame, a translational transmission mechanism and a translational rigidity changing mechanism, wherein the translational transmission mechanism is fixedly connected with a platform bottom plate of the rotational rigidity simulation platform 2', the translational input of the base input end 1 'is transmitted to the translational transmission mechanism, and the translational rigidity changing mechanism is fixed on the translational platform support frame and connected with the translational transmission mechanism and is used for adjusting the rigidity of the translational transmission mechanism in a mode of changing the rigidity of the leaf spring, so that the translational rigidity of the base input end 1' is adjusted.

The translation platform support frame comprises an upper platform 319 and a lower platform 320, and the upper platform 319 is in supporting connection with the lower platform 320 through a section bar 321.

The translational transfer mechanism comprises a translational guide rail group 301, a transmission shaft 302, a guide shaft 303, a guide sliding block 304, a supporting spring 305 and a translational assembly, wherein a guide bearing part of the translational guide rail group 301 is fixed on the surface of an upper platform 319, and a moving part of the translational guide rail group 301 is fixedly connected with the bottom surface of a platform bottom plate of the rotational stiffness simulation platform 2'; the smoothing assembly comprises a connecting slide block 306, a translation slide block 307 and a translation slide rail 308, wherein the translation slide rail 308 is fixed on an upper platform 319 and is arranged in parallel with the translation guide rail group 301, the number of the translation slide blocks 307 is two and is distributed on two sides of the connecting slide block 306, the two translation slide blocks 307 and the connecting slide block 306 form a slide block group, and the slide block group linearly slides on the translation slide rail 308; one end of a transmission shaft 302 is fixed with a connecting sliding block 306, the other end of the transmission shaft 302 is fixedly connected with a platform bottom plate of a rotational stiffness simulation platform 2', one end of a guide shaft 303 is fixedly connected with a lower platform 320, the other end of the guide shaft 303 is fixedly connected with the bottom of a translational sliding rail 308, the other end of the guide shaft 303 passes through the translational sliding rail 308 downwards through a screw, the upper platform 319 is connected with the upper end of the guide shaft 303, the fixed connection of the three is realized, a guide sliding block 304 is sleeved on the guide shaft 303, the guide shaft 303 slides up and down, a support spring 305 is sleeved on the guide shaft 303, one end of the support spring 305 is abutted with the bottom of the guide sliding block 304, the other end of the support spring 305 is abutted with the lower platform 320, and the support spring 305 provides a force opposite to the movement direction of the guide sliding block 304.

The translational rigidity-changing mechanism comprises a rigidity-adjusting cylinder 309, two linkage blocks 310 rotationally connected with a section bar 321, two pushing blocks 311 symmetrically arranged along a guide slide block 304, two linear bearing groups 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 arranged on the section bar 321 and the linkage blocks 310, bearings are arranged between the two bearing seats 318 to realize the rotation of the linkage blocks 310 relative to the section bar 321, the two pushing blocks 311 horizontally slide along the two linear bearing groups 312, one ends of the two leaf springs 313 are respectively fixedly connected with the two pushing blocks 311, the other ends of the two leaf springs 313 are respectively fixedly connected with two sides of the guide slide block 304, one ends of the two first connecting rods 314 are respectively rotationally connected with two sides of one translational slide block 307, the other ends of the two first connecting rods 314 are respectively and rotatably connected with two sides of one end of the guide slide block 304, one ends of the two second connecting rods 315 are respectively and rotatably connected with two sides of the other translational slide block 307, the other ends of the two second connecting rods 315 are respectively and rotatably connected with two sides of the other end of the guide slide block 304, one ends of the two third connecting rods 316 are respectively and rotatably connected with one end of the two pushing blocks 311, the other ends of the two third connecting rods 316 are respectively and rotatably connected with two ends of one linkage block 310, one ends of the two fourth connecting rods 317 are respectively and rotatably connected with the other ends of the two pushing blocks 311, and the output end of the rigidity adjusting cylinder 309 is fixedly connected with one pushing block 311.

The translation of the base input end 1' in the direction of the translation guide rail group 301 is transmitted to the smoothing assembly through the rotary platform support frame and the transmission shaft 302, so that the sliding block group moves linearly along the translation guide rail 308, and the linear motion of the sliding block group is converted into the vertical linear motion of the guide sliding block 304 through the first connecting rod 314 and the second connecting rod 315. The movement of the guide slider 304 is disturbed by the leaf spring 313 and the support spring 305. The leaf spring 313 is composed of two symmetrically stacked spring steel sheets, and a cavity is formed between the two spring steel sheets. The stiffness of the leaf spring 313 is related to the width of the cavity, the greater the bending stiffness of the leaf spring 313 and the greater the resistance to deformation. Therefore, the output rigidity of the translational rigidity-changing mechanism can be changed by changing the width of the cavity, so that the rigidity of the translational transmission mechanism is adjusted, and the translational rigidity of the input end 1' of the base is adjusted.

The rigid adjusting cylinder 309 drives the pushing block 311 to slide on the linear bearing group 312, and the pushing block 311 on the other side synchronously moves through the two linkage blocks 310, the third connecting rod 316 and the fourth connecting rod 317 on the two sides of the two linkage blocks 310, and the movement of the pushing block 311 can squeeze the leaf spring 313, so that the width of the cavity of the leaf spring 313 is changed. By varying the width of the cavity of the leaf spring 313 in real time, the stiffness of the slider group in the direction of movement is controllable and time-varying.

The structure of the second dynamic stiffness simulation platform 4' is the same as that of the first translational stiffness simulation platform 3 ', and the principle of adjusting the stiffness of the two is the same naturally, so the structure of the second dynamic stiffness simulation platform 4' is not repeated, the translational guide rail group 402 and the sliding component of the second dynamic stiffness simulation platform 4 are arranged in quadrature with the translational guide rail group 301 and the sliding component of the first translational stiffness simulation platform 3 ', that is, the second dynamic stiffness simulation platform 4' is orthogonal with the motion direction of the first translational stiffness simulation platform 3 ', the transmission shaft 401 of the second dynamic stiffness simulation platform 4' is fixedly connected with the lower platform 320 of the first translational stiffness simulation platform 3 ', and the translational guide rail group 402 of the second dynamic stiffness simulation platform 4' is connected between the upper platform 403 of the second dynamic stiffness simulation platform 4' and the lower platform 320 of the first translational stiffness simulation platform 3 '.

The translation of the base input end 1 'in the direction of the translation guide rail group 402 is transmitted to a transmission shaft 401 of the second dynamic stiffness simulation platform 4' through the rotation platform support frame and the platform support frame of the first translation stiffness simulation platform 3 ', and then transmitted to a sliding component of the second dynamic stiffness simulation platform 4'.

The translational guide rail set 301 is perpendicular to the movement direction of the translational guide rail set 402, and the translational degrees of freedom of the two perpendicular movement directions of the base input end 1 ' are adjusted through the translational rigidity changing mechanism of the first translational rigidity simulation platform 3' and the second translational rigidity simulation platform 4 '.

Example 3

As shown in fig. 14 to 16, the active stiffness-variable modularized pedestal provided in embodiment 3 of the present invention includes a pedestal input end 1 ", a rotational stiffness simulation platform 2", a first translational stiffness simulation platform 3″ and a second translational stiffness simulation platform 4″, the structure of the pedestal input end 1″ is the same as that of the pedestal input end 1 of embodiment 1, and the structure of the rotational stiffness simulation platform 2″ is the same as that of the rotational stiffness simulation platform 2 of embodiment 1, so that detailed descriptions of the specific structures of the pedestal input end 1″ and the rotational stiffness simulation platform 2″ are omitted.

The first translational rigidity simulation platform 3 ' comprises a transmission shaft 3-1, a platform supporting plate 3-2, a guide rail group 3-3 and a translational rigidity-changing mechanism 3-4, wherein a guide bearing part of the guide rail group 3-3 is arranged on the platform supporting plate 3-2, a moving part of the guide rail group 3-3 is fixedly connected with the bottom of a platform bottom plate of the rotational rigidity simulation platform 2', the translational rigidity-changing mechanism 3-4 is connected with the platform bottom plate through the transmission shaft 3-1, and the translational rigidity-changing mechanism 3-4 adjusts the self rigidity in a mode of changing pretightening force so as to realize the translational rigidity adjustment of the base input end 1 '.

The translational rigidity-changing mechanism 3-4 comprises a rigidity-adjusting sliding block 3-4-1, a rigidity-adjusting guide rail 3-4-2, a spring steel wire rope 3-4-3, a fixed wheel 3-4-4, a guide wheel 3-4-5, a rope pressing wheel 3-4-6, a translational rope receiving wheel 3-4-7, a worm 3-4-8, a worm wheel 3-4-9, a bearing seat 3-4-10, a translational rigidity-adjusting motor 3-4-11 and a reversing wheel 3-4-12; wherein, the rigidity adjusting guide rail 3-4-2 is fixedly connected on the platform supporting plate 3-2 and parallel to the guide rail group 3-3, the rigidity adjusting slide block 3-4-1 linearly slides on the rigidity adjusting guide rail 3-4-2, and two ends of the transmission shaft 3-1 are respectively fixedly connected with the rigidity adjusting slide block 3-4-1 and the platform bottom plate of the rotational rigidity simulation platform 2'.

The fixed wheels 3-4-4 and the translational rope collecting wheels 3-4-7 are positioned at one end of the rigidity adjusting guide rail 3-4-2, and the number of the rope pressing wheels 3-4-6 is two and are fixed at two ends of the rigidity adjusting sliding block 3-4-1; the guide wheel 3-4-5 is positioned at the other end of the rigid adjusting guide rail 3-4-2; one end of the spring wire rope 3-4-3 is fixed on the fixed wheel 3-4-4, and the other end of the spring wire rope 3-4-3 is fixed on the translational rope collecting wheel 3-4-7 after passing through one rope pressing wheel 3-4-6, the guide wheel 3-4-5 and the other rope pressing wheel 3-4-6 in sequence.

The translational rigidity-adjusting motor 3-4-11 is fixed on the platform supporting plate 3-2, the output end of the translational rigidity-adjusting motor 3-4-11 is connected with the worm 3-4-8 through a coupler, the worm 3-4-8 is meshed with the worm wheel 3-4-9 arranged on the translational rigidity-adjusting wheel 3-4-7, the translational rigidity-adjusting motor 3-4-11 controls the rotation of the translational rigidity-adjusting wheel 3-4-7 through the cooperation of the worm 3-4-8 and the worm wheel 3-4-9, and then the spring steel wire rope 3-4-3 controls and adjusts the pretightening force applied to the movement of the rigidity-adjusting sliding block 3-4-1 along the rigidity-adjusting guide rail 3-4-2.

A reversing wheel 3-4-12 for changing the direction of the spring wire rope 3-4-3 is arranged between the fixed wheel 3-4-4 and the rope pressing wheel 3-4-6, between the rope pressing wheel 3-4-6 and the guide wheel 3-4-5 and between the rope pressing wheel 3-4-6 and the translational rope collecting wheel 3-4-7.

The structure of the second translational rigidity simulation platform 4' is the same as that of the first translational rigidity simulation platform 3 ', and the principle of rigidity adjustment of the second translational rigidity simulation platform and the first translational rigidity simulation platform is the same naturally, so that the structure of the second translational rigidity simulation platform 4' is not repeated.

The guide rail group 4-2 of the second translational rigidity simulation platform 4 'is arranged in an orthogonal manner with the guide rail group 3-3 of the first translational rigidity simulation platform 3', namely, the second translational rigidity simulation platform 4 'is orthogonal with the movement direction of the first translational rigidity simulation platform 3', the transmission shaft of the second translational rigidity simulation platform 4 'is fixedly connected with the platform supporting plate 3-2 of the first translational rigidity simulation platform 3', and the guide rail group 4-2 of the second translational rigidity simulation platform 4 'is connected between the platform supporting plate of the second translational rigidity simulation platform and the platform supporting plate 3-2 of the first translational rigidity simulation platform 3'.

The translation of the base input end 1 'in the direction of the guide rail set 4-2 is transmitted to the transmission shaft of the second dynamic stiffness simulation platform 4' through the transmission shaft 3-1 of the rotating platform support frame and the first translational stiffness simulation platform 3 'and the platform support plate 3-2, and then transmitted to the sliding component of the second dynamic stiffness simulation platform 4'.

The guide rail group 3-1 is perpendicular to the movement direction of the guide rail group 4-2, and the translational degree of freedom of the two movement directions of the base input end 1 ' are adjusted by the translational rigidity changing mechanism of the first translational rigidity simulation platform 3' and the second translational rigidity simulation platform 4 '.

The three embodiments detail the structure of the active rigidity-variable modularized base with three different structures, and embodiments 1-3 all transmit motion through the input end of the base, utilize the mechanical structure to transmit and convert the motion to the rigidity-variable mechanism, and are interfered by the rigidity-variable mechanism, and the rigidity of the flexible base in the motion degree of freedom can be adjusted in real time by changing the rigidity of the rigidity-variable mechanism in real time, and then the rigidity at the input end of the base can be controlled through rigidity conversion. In this way, the stiffness of the boom is simulated as varying in real time during movement.

While embodiments of the present invention have been illustrated and described above, it will be appreciated that the above described embodiments are illustrative and should not be construed as limiting the invention. Variations, modifications, alternatives and variations of the above-described embodiments may be made by those of ordinary skill in the art within the scope of the present invention.

The above embodiments of the present invention do not limit the scope of the present invention. Any other corresponding changes and modifications made in accordance with the technical idea of the present invention shall be included in the scope of the claims of the present invention.

Claims

1. The active rigidity-changing modularized base is characterized by comprising a base input end, a rotational rigidity simulation platform and a translational rigidity simulation platform; wherein,

The rotation stiffness simulation platform comprises a rotation platform support frame, a motion conversion mechanism and a rotation stiffness variation mechanism, wherein the rotation stiffness variation mechanism is arranged on the rotation platform support frame, the input end of the base and the rotation stiffness variation mechanism are respectively connected with the motion conversion mechanism, the motion conversion mechanism is used for converting rotation of the input end of the base into translation, and the rotation stiffness variation mechanism is used for adjusting self stiffness in a mode of changing the effective number of turns of a spring and acts on the motion conversion mechanism to realize adjustment of rotation stiffness of the input end of the base;

The translational rigidity simulation platform comprises a first transmission shaft, a first platform supporting plate, a first guide rail group and a first translational rigidity-changing mechanism, wherein a guide bearing piece of the first guide rail group is arranged on the first platform supporting plate, a moving piece of the first guide rail group is fixedly connected with the bottom of the rotating platform supporting frame, the first translational rigidity-changing mechanism is connected with the rotating platform supporting frame through the first transmission shaft, and the first translational rigidity-changing mechanism is used for adjusting self rigidity in a moment-changing mode to realize adjustment of translational rigidity of the input end of the base;

Or the translational rigidity simulation platform comprises a translational platform support frame, a translational transmission mechanism and a second translational rigidity-changing mechanism, wherein the translational transmission mechanism is fixedly connected with the rotational platform support frame, the translational movement input by the input end of the base is transmitted to the translational transmission mechanism, and the second translational rigidity-changing mechanism is fixed on the platform support frame and connected with the translational transmission mechanism and is used for adjusting the rigidity of the translational transmission mechanism in a mode of changing the rigidity of the leaf spring so as to realize the adjustment of the translational rigidity of the input end of the base;

Or the translational rigidity simulation platform comprises a third transmission shaft, a second platform supporting plate, a second guide rail group and a third translational rigidity-changing mechanism, wherein a guide bearing piece of the second guide rail group is arranged on the second platform supporting plate, a moving piece of the second guide rail group is fixedly connected with the bottom of the rotating platform supporting frame, the third translational rigidity-changing mechanism is connected with the rotating platform supporting frame through the third transmission shaft, and the third translational rigidity-changing mechanism is used for adjusting self rigidity in a mode of changing pretightening force so as to realize adjustment of translational rigidity of the input end of the base.

2. The active variable stiffness modular base of claim 1, wherein the rotational variable stiffness mechanism comprises a top cone seat and two rotational variable stiffness adjustment units, the two rotational variable stiffness adjustment units respectively reaching two sides of the top cone seat through top cone tips;

The two rotation rigidity-changing adjusting units comprise a rotation rigidity-adjusting motor, a first coupler, ball splines, a rotating shaft, springs, a pedestal, clamping pieces, bearings, shaft sleeves and end covers, wherein the rotation rigidity-adjusting motor is fixed on a rotating platform supporting frame, an output shaft of the rotation rigidity-adjusting motor is connected with the spline shaft of the ball splines through the first coupler, the flanges of the ball splines are connected with the rotating shaft, the shaft sleeves are sleeved at the end parts of the rotating shaft, the springs and the bearings are respectively sleeved at the two ends of the shaft sleeves, the end covers are sleeved at the outer sides of the springs and the bearings, and top cone holes matched with the top cones are respectively formed in the end covers and the top cone seats;

The pedestal comprises a T-shaped base and a sleeve, the T-shaped base is mounted on the rotary platform support frame and is fixedly connected with the sleeve, the sleeve is sleeved on the outer side of the spring, the clamping piece is fixedly connected with the sleeve and is clamped into the spring, the rotation of an output shaft of the rotary rigidity adjusting motor is controlled, the rotation of the output shaft of the rotary rigidity adjusting motor is sequentially transmitted to the spring through a first coupler, a ball spline and a rotating shaft, the shaft sleeve is transmitted to the spring, the spring is abutted to the clamping piece to rotate along the radial direction, the effective number of turns is changed, and the time-varying rigidity output of the end cover to the tip cone seat is realized.

3. The active rigidity-changing modularized base according to claim 2, wherein the clamping piece is a limit bolt, an adjusting hole for adjusting the position of the limit bolt is formed in the sleeve, the head of the limit bolt is clamped at the outer side of the adjusting hole, and a screw rod of the limit bolt passes through the adjusting hole downwards and is clamped into the spring.

4. The active rigidity-changing modularized base according to claim 2, wherein the clamping piece comprises a clamping cone and a clamping cone block, the clamping cone and the clamping cone block are of an integrated structure or a split structure, the clamping cone block is fixed on the sleeve through a fastening bolt, waist-shaped holes for adjusting positions of the fastening bolt are respectively formed in the clamping cone block and the sleeve, avoidance holes are further formed in the sleeve, and the clamping cone downwards penetrates through the avoidance holes and then is clamped into the spring.

5. The active variable stiffness modular base of any of claims 2-4, wherein the motion conversion mechanism comprises a second coupling, a sector gear, and a sliding assembly; the sliding assembly comprises a sliding block and a sliding rail which are in sliding fit, a rack is machined on one side of the sliding block, a top cone seat is fixedly mounted on the sliding block, rotation of the input end of the base is transmitted to the sector gear through the second coupling, and the sector gear is meshed with the rack to be converted into translation of the sliding block on the sliding rail.

6. The active stiffness-changing modular base of claim 5, wherein the rotating platform support comprises a platform bottom plate and a platform top plate connected by profiles, and the T-shaped base, the slide rail and the rotating stiffness-adjusting motor are fixedly mounted on the platform bottom plate.

7. The active variable stiffness modular base of claim 6, wherein the base input comprises a triangular connecting frame and a U-shaped frame which are rotatably connected, wherein the triangular connecting frame is provided with a connecting hole for connecting with a power source; the two ends of the U-shaped frame are outwards provided with table edges, and the table edges are fixed on the platform top plate through screws.

8. The active variable stiffness modular base of claim 6, wherein the T-shaped base is fixedly mounted to the platform floor by two L-shaped connection blocks, a gap between the two L-shaped connection blocks allowing the slide rail to pass through.

9. The active stiffness-changing modular base of claim 6, wherein the rotary stiffness-adjusting motor is fixedly mounted to the platform floor via a motor mount.

10. The active stiffness-changing modularized base according to claim 6, wherein the first translational stiffness-changing mechanism comprises a sliding component and two translational stiffness-changing adjusting units which are symmetrically arranged with the sliding component as a center, and the two translational stiffness-changing adjusting units are respectively in close contact with the sliding component, so that the translational stiffness of the input end of the base can be adjusted in real time by the sliding component.

11. The active stiffness-changing modularized base according to claim 10, wherein the translational stiffness-changing adjusting unit comprises an arc track, a track rotation center column, an inscribed sliding block, a guiding connecting arm, a guiding connecting rod, a pressure spring, a first translational stiffness-adjusting motor, a stiffness-adjusting rotation center column, a driving bevel gear, a driven bevel gear and a linear bearing; wherein,

The track rotation center column is fixed on the platform bottom plate; one end of the arc track is tightly contacted with the sliding component, and the other end of the arc track is fixedly connected with the track rotation center column, so that the sliding component extrudes the arc track, and the arc track rotates around the track rotation center column;

The rigidity-adjusting rotation center column and the first translation rigidity-adjusting motor are arranged on the platform bottom plate, the driving bevel gear is arranged at the output end of the first translation rigidity-adjusting motor, the driven bevel gear is sleeved on the rigidity-adjusting rotation center column and meshed with the driving bevel gear, and the first translation rigidity-adjusting motor drives the output end of the rigidity-adjusting rotation center column to rotate through the meshing of the driving bevel gear and the driven bevel gear;

the fixed end of the guide connecting arm is fixedly connected with the output end of the rigidity-adjusting rotary center column, and the movable end of the guide connecting arm is provided with a mounting piece for mounting the guide connecting rod;

One end of the linear bearing is fixed on the guide connecting arm, and the other end of the linear bearing is connected with the guide connecting rod, so that the guide connecting rod can be subjected to telescopic adjustment along the linear bearing;

one side of the inscription sliding block is arranged on the guide connecting rod; the other side of the inscription slide block is matched with the inner wall of the circular arc track, so that the inscription slide block drives the guide connecting rod to move along the inner wall of the circular arc track;

One end of the pressure spring is fixed on the fixed end of the guide connecting arm, the other end of the pressure spring is connected with the guide connecting rod, so that the first translational rigidity adjusting motor is used for controlling the rigidity adjusting rotation center column in real time, adjusting the moment of the pressure spring and matching with the expansion and contraction of the pressure spring, and further realizing the real-time adjustment of translational rigidity of the sliding component to the input end of the base.

12. The active rigidity-changing modularized base according to claim 11, wherein the sliding assembly comprises a sliding block and a linear sliding rail which are in sliding fit, the linear sliding rail is fixed on the platform bottom plate, the first transmission shaft is fixed on the sliding block, a roller is sleeved on the first transmission shaft, one end of the circular arc rail is in tight contact with the roller, and when the first transmission shaft drives the sliding block to translate on the linear sliding rail, the roller rolls and extrudes the circular arc rail, so that the circular arc rail rotates around the rail revolution center column.

13. The active variable stiffness modular base of claim 6, wherein the translational transfer mechanism comprises a translational guide set, a second drive shaft, a smoothing assembly, a guide shaft, a guide slide, and a support spring; the bearing guide piece of the translation guide rail group is fixed on the translation platform support frame, and the moving piece of the translation guide rail group is fixedly connected with the platform bottom plate; the smoothing component comprises a connecting slide block, a translation slide block and a translation slide rail, wherein the translation slide rail is arranged in parallel with the translation slide rail group, the number of the translation slide blocks is two and is distributed on two sides of the connecting slide block, and the two translation slide blocks and the connecting slide block linearly slide on the translation slide rail; one end of the second transmission shaft is fixedly connected with the connecting sliding block, the other end of the second transmission shaft is fixedly connected with the platform bottom plate, one end of the guide shaft is fixedly connected with the translational platform support frame, the other end of the guide shaft is fixedly connected with the bottom of the translational sliding rail, the guide sliding block is sleeved on the guide shaft and slides up and down along the guide shaft, the supporting spring is sleeved on the guide shaft, one end of the supporting spring is abutted to the bottom of the guide sliding block, and the other end of the supporting spring is abutted to the translational platform support frame.

14. The active rigidity-changing modularized base according to claim 13, wherein the second dynamic rigidity-changing mechanism comprises a rigidity-changing cylinder, two linkage blocks rotationally connected with the translational platform support frame, and two pushing blocks, two linear bearing groups, two first connecting rods, two second connecting rods, two third connecting rods and two fourth connecting rods symmetrically arranged along the guiding sliding block, wherein the two pushing blocks horizontally slide along the two linear bearing groups, one ends of the two leaf springs are fixedly connected with the two pushing blocks respectively, the other ends of the two leaf springs are fixedly connected with two sides of the guiding sliding block respectively, one ends of the two first connecting rods are rotationally connected with two sides of one translational sliding block respectively, the other ends of the two first connecting rods are rotationally connected with two sides of one end of the guiding sliding block respectively, one ends of the two second connecting rods are rotationally connected with two sides of the other sliding block respectively, one ends of the two third connecting rods are rotationally connected with one ends of the two pushing blocks respectively, one ends of the two leaf springs are rotationally connected with two ends of the other end of the guiding sliding block respectively, one end of the two leaf springs are rotationally connected with two ends of the other translational sliding block respectively, the two ends of the two translational platform support frame are rotationally connected with two ends of the other translational sliding block respectively, the two ends of the two translation rigidity-changing mechanism.

15. The active variable stiffness modular base of claim 14, wherein the leaf spring is comprised of two spring steel sheets with a cavity therebetween.

16. The active rigidity-changing modularized base of claim 15, wherein the translational platform support comprises an upper platform and a lower platform, the upper platform and the lower platform are connected through a section bar support, a bearing guide piece of the translational guide rail group is fixed on the surface of the upper platform, the guide shaft, the rigidity-adjusting cylinder and two linear bearing groups are fixed on the surface of the lower platform, and the linkage block is connected with the section bar in a rotating way.

17. The active stiffness-changing modularized base according to claim 6, wherein the third translational stiffness-changing mechanism comprises a stiffness-adjusting sliding block, a stiffness-adjusting guide rail, a spring wire rope, a fixed wheel, a guide wheel, a rope pressing wheel, a translational rope receiving wheel, a worm wheel, a bearing seat and a second translational stiffness-adjusting motor; wherein,

The rigidity adjusting guide rail is fixedly connected to the second platform supporting plate and parallel to the second guide rail group, the rigidity adjusting sliding block linearly slides on the rigidity adjusting guide rail, and two ends of the third transmission shaft are respectively and fixedly connected with the rigidity adjusting sliding block and the platform bottom plate;

The fixed wheels and the translational rope collecting wheels are positioned at one end of the rigidity adjusting guide rail, and the number of the rope pressing wheels is not less than two and is fixed at two ends of the rigidity adjusting sliding block; the guide wheel is positioned at the other end of the rigidity adjusting guide rail; one end of the spring wire rope is fixed on the fixed wheel, and the other end of the spring wire rope is fixed on the translational rope collecting wheel after passing through one rope pressing wheel, the guide wheel and the other rope pressing wheel in sequence;

The second translational rigidity adjusting motor and the bearing seat are respectively fixed on the second platform supporting plate, the output end of the second translational rigidity adjusting motor is connected with one end of the worm through a third coupler, the other end of the worm is rotationally connected with the bearing seat, the worm wheel is sleeved on the translational steel collecting wheel and meshed with the worm, rotation output by the second translational rigidity adjusting motor is transmitted to the translational steel collecting wheel through the cooperation of the worm and the worm wheel, and then the spring steel wire rope is used for controlling the rigidity adjusting sliding block to move along the rigidity adjusting guide rail to receive pretightening force, so that translational rigidity of the input end of the base is adjusted.

18. The active variable stiffness modular base of claim 17, wherein a reversing wheel for changing the direction of the spring wire rope is disposed between the fixed wheel and the sheave, between the sheave and the guide wheel, and between the sheave and the translational sheave.

19. The active stiffness-changing modularized base of claim 13, wherein the number of the translational stiffness simulation platforms is at least two, the translational stiffness simulation platforms are distributed up and down and are connected with each other, and the movement directions of the first guide rail group or the second guide rail group or the translational guide rail group of each translational stiffness simulation platform are different.

20. The active variable stiffness modular base of claim 19, wherein the number of translational stiffness analog platforms is two, and the directions of movement of the first or second or translational guide sets of the two translational stiffness analog platforms are perpendicular.