CN117921745B

CN117921745B - Time-varying stiffness base system for multidirectional motion conversion

Info

Publication number: CN117921745B
Application number: CN202410343293.7A
Authority: CN
Inventors: 胡金鑫; 于鹏; 吴清文; 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: 2024-05-24
Anticipated expiration: 2044-03-25
Also published as: CN117921745A

Abstract

The invention relates to the technical field of space mechanics simulation, in particular to a time-varying rigidity base system for multidirectional motion conversion, which is characterized in that a rotational rigidity simulation platform based on a rope drive mechanism converts rotation from an input end of a flexible base into translation and performs rigidity adjustment; simultaneously, three different translational stiffness simulation platforms based on springs, sliding rails and leaf springs are provided. The rotation and dynamic stiffness simulation platforms are stacked and connected to form the time-varying stiffness base system capable of simultaneously completing rotation stiffness and dynamic stiffness adjustment. The system can simulate real-time rigidity changes of multiple degrees of freedom 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 counteracts 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.

Description

Time-varying stiffness base system for multidirectional motion conversion

Technical Field

The invention relates to the technical field of space mechanics simulation, in particular to a time-varying rigidity base system for multidirectional motion conversion.

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 aims to solve the problems, and provides a time-varying rigidity base system for multi-direction motion conversion, which can simulate the simultaneous motion of the large arm and the small arm of a space station, and the large arm is used as a base of the small arm, so that rigidity change caused by configuration change in the motion process is studied, and the disturbance motion law generated in the combined arm under the joint motion of the large arm and the small arm of the space station is studied.

The invention provides a multidirectional motion conversion time-varying rigidity base system, which comprises a flexible base input end, a flexible base cover plate, a rotational rigidity simulation platform and a translational rigidity simulation platform, wherein the flexible base cover plate is arranged on the flexible base input end; wherein the flexible base input end is mounted to the top surface of the flexible base cover plate through a supporting table; the rotational stiffness simulation platform is connected with the bottom surface of the flexible base cover plate through a section bar; the translational rigidity simulation platform is connected with the rotational rigidity simulation platform through a transmission shaft;

The rotating stiffness simulation platform comprises a motion conversion mechanism and a rotating stiffness variation mechanism; the motion conversion mechanism is connected with the input end of the flexible base through a coupler and is used for converting the rotation of the input end of the flexible base into the translation diffused to the periphery; the rotation rigidity-changing mechanism coaxially controls the motion conversion mechanism, and the pretightening force of the rotation rigidity-changing mechanism on the motion conversion mechanism is controlled in real time, so that the motion rigidity of the motion conversion mechanism is controlled;

The translational rigidity simulation platform comprises a first translational rigidity-changing mechanism, a first guide rail group, a sliding adjusting assembly and a platform bottom plate, wherein the number of the first translational rigidity-changing mechanisms is not less than one, the sliding adjusting assembly and the first translational rigidity-changing mechanism are both arranged on the platform bottom plate, and the first translational rigidity-changing mechanism adjusts the translational rigidity of the rotational rigidity simulation platform in real time through the sliding adjusting assembly and a transmission shaft; the first guide rail group is parallel to the sliding adjusting component and is fixed at two ends of the platform bottom plate, and the rotating rigidity simulation platform moves on the first guide rail group through the heightening frame;

Or the translational rigidity simulation platform comprises a platform supporting plate, a second guide rail group and a second translational rigidity-changing mechanism, wherein the second guide rail group carries the rotational rigidity-changing mechanism, and the second translational rigidity-changing mechanism is used for adjusting the rigidity of the platform by changing the effective number of turns of the spring so as to change the translational rigidity of the input end of the flexible base;

Or the translational rigidity simulation platform comprises an upper platform, a lower platform, a translational transmission mechanism and a third translational rigidity-changing mechanism, wherein the translational transmission mechanism is connected with the rotational rigidity simulation platform through a transmission shaft and is used for transmitting the translational movement input by the input end of the flexible base to the translational transmission mechanism; the upper platform and the lower platform are connected through a section bar support, and the third translational rigidity-changing mechanism is fixed on the lower platform and connected with the translational transmission mechanism and is used for adjusting the rigidity of the translational transmission mechanism by changing the rigidity of the elastic sheet spring, so that the translational rigidity of the input end of the flexible base is adjusted.

Further, the rotational stiffness simulation platform further comprises a support bottom plate; the support bottom plate is fixed on the bottom surface of the flexible base cover plate through a section bar; the motion conversion mechanism is arranged on the supporting bottom plate; the rotary rigidity-changing mechanism is arranged on the supporting bottom plate through a supporting block; the supporting bottom plate is arranged on the translational rigidity simulation platform and is connected with the translational rigidity simulation platform through a transmission shaft.

Further, the motion conversion mechanism comprises a rotary support frame, a traction turntable, a connecting rod, a motion conversion sliding rail and a motion conversion sliding block matched with the motion conversion sliding rail; wherein,

The rotary support frame comprises a rotary support table, a rotary support arm and at least two rotary support frame bases, and the rotary support table and the rotary support arm are of an integrated structure; the number of the rotary support arms is consistent with that of the rotary support frame base, one ends of the rotary support arms are uniformly arranged on the circumference of the rotary support table, and the other ends of the rotary support arms are arranged on the rotary support frame base, so that the rotary support frame base can jack up the rotary support table through the rotary support arms;

the number of the motion conversion sliding rails is the same as that of the rotation supporting arms, and the motion conversion sliding rails are arranged on the rotation supporting arms; the input end of the flexible base is coaxially connected with the traction turntable through a coupler, and the motion conversion sliding block is connected with the traction turntable through a connecting rod, so that the rotation of the input end of the flexible base is converted into the translation of the motion conversion sliding block on the motion conversion sliding rail through the traction turntable through the connecting rod.

Further, the rotary rigidity-changing mechanism comprises a rotary guide wheel, a rotary rope collecting wheel, a belt pulley, a tensioning wheel and a rotary rigidity-adjusting motor; wherein,

The number of the belt pulleys and the tensioning wheels is consistent with that of the rotating support frame bases, the belt pulleys are sleeved on the rotating support frame bases and lower than the rotating support arms, and the belt sleeved on and connected with the belt pulleys is lower than the rotating support arms; the tensioning wheels are consistent in height with the belt pulleys and are uniformly distributed along the circumferential direction of the rotary supporting table, so that the belt is pressed by the tensioning wheels towards the rotary supporting table;

The rotating rigidity-adjusting motor is fixed on the supporting bottom plate, the output end of the rotating rigidity-adjusting motor is connected with the worm through the coupler, the worm is meshed with the worm wheel arranged on any belt pulley, the rotating rigidity-adjusting motor controls the rotation of the belt pulley through the cooperation of the worm and the worm wheel, and further controls the rotation of other belt pulleys through the belt;

The number of the rotating rope collecting wheels is consistent with that of the belt pulleys, and the rotating rope collecting wheels and the belt pulleys are coaxially arranged on a base of the rotating support frame, so that the belt pulleys drive the rotating rope collecting wheels to synchronously rotate; the number of the rotating guide wheels is consistent with that of the rotating rope collecting wheels, and the rotating guide wheels are installed on the rotating support arm close to the rotating rope collecting wheels;

the motion conversion sliding block is fixedly provided with a spring steel wire rope connected with a rotating rope collecting wheel on the base of the adjacent rotating support frame, and the rotating rigidity adjusting motor adjusts the pretightening force of the spring steel wire rope through the belt pulley and the rotating rope collecting wheel so as to adjust the rotating rigidity of the input end of the flexible base.

Further, the number of the first translational rigidity-changing mechanisms is not less than one, and each translational rigidity-changing mechanism comprises two first translational rigidity-changing mechanisms; the number of the sliding adjusting components is consistent with the number of the groups of the first translational rigidity-changing mechanisms, and each group of the first translational rigidity-changing mechanisms is respectively positioned at two ends of the sliding adjusting component and is in close contact with the sliding adjusting component, so that the translational rigidity of the rotary rigidity simulation platform is adjusted in real time by the two first translational rigidity-changing mechanisms through the transmission shaft and the sliding adjusting component; the two first guide rail groups are parallel to the sliding adjusting assembly and fixed at two ends of the platform bottom plate, and the supporting bottom plate moves on the first guide rail groups through the heightening frame.

Further, the first translational rigidity-changing mechanism comprises an arc track, a track rotation center column, an inscription sliding block, a guiding connecting arm, a guiding connecting rod, a pressure spring, a motor, a rigidity-adjusting rotation center column, a bevel gear group 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 adjusting component, and the other end of the arc track is fixedly connected with the track rotation center column, so that the sliding adjusting component extrudes the arc track, and the arc track rotates around the track rotation center column;

The motor drives the output end of the rigid regulating rotation center column to rotate through the bevel gear group;

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 motor controls the rigid-adjusting rotation center column in real time to complete moment adjustment of the pressure spring and is matched with the expansion and contraction of the pressure spring, and further the translation rigidity of the input end of the base is adjusted in real time by the sliding component.

Further, the sliding adjusting assembly comprises a connecting sliding block and a translational sliding rail, the translational sliding rail is fixed on the platform bottom plate, the transmission shaft is fixed on the connecting sliding block, a roller is sleeved on the transmission shaft, one end of the arc rail is in close contact with the roller, and when the transmission shaft drives the connecting sliding block to translate on the translational sliding rail, the roller rolls and extrudes the arc rail, so that the arc rail rotates around the rail rotation center column.

Further, the second translational rigidity-changing mechanism comprises a top cone seat and two rigidity-changing adjusting units, the two rigidity-changing adjusting units are respectively jacked to two sides of the top cone seat through top cones, the top cone seat is connected with the supporting bottom plate through sectional materials, and the two rigidity-changing adjusting units control the translational rigidity of the rotational rigidity simulation platform through the top cone seat and the sectional materials;

The two rigidity-changing adjusting units comprise a driving motor, a first coupling, ball splines, a rotating shaft, springs, a pedestal, clamping pieces, bearings, shaft sleeves and end covers, wherein the driving motor is fixed on a platform supporting plate;

The pedestal comprises a T-shaped base and a sleeve, the T-shaped base is mounted on a platform supporting plate 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 output shaft of the driving motor is controlled to rotate, the output shaft is sequentially transmitted to the spring through a first coupling, a ball spline, a rotating shaft and a shaft sleeve, 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.

Further, the translation transmission mechanism comprises a translation guide rail group, a sliding component, a guide shaft, a guide sliding block and a support spring; wherein, the bearing guide piece of the translational guide rail group is fixed on the upper platform, and the moving piece of the translational guide rail group is fixedly connected with the supporting bottom plate; the sliding component comprises translational connecting sliding blocks, translational sliding blocks and translational adjusting sliding rails, the translational adjusting sliding rails are arranged in parallel with the translational guide rail group, the number of the translational sliding blocks is two and is distributed on two sides of the translational connecting sliding blocks, and the two translational sliding blocks and the translational connecting sliding blocks linearly slide on the translational adjusting sliding rails; one end of the transmission shaft is fixed with the translation connecting sliding block, and the other end of the transmission shaft is connected and fixed with the supporting bottom plate; one end of the guide shaft is fixedly connected with the lower platform, the other end of the guide shaft is fixedly connected with the bottom of the upper platform, and the guide shaft is connected with the upper end of the guide shaft after downwards penetrating through the translational adjustment slide rail and the upper platform through bolts, so that the translational adjustment slide rail, the upper platform and the guide shaft are fixedly connected; the guide slide block is sleeved on the guide shaft and slides up and down along the guide shaft, the support spring is sleeved on the guide shaft, one end of the support spring is abutted with the bottom of the guide slide block, and the other end of the support spring is abutted with the lower platform.

Further, the third translational rigidity-changing mechanism comprises a rigidity-adjusting cylinder, two linkage blocks rotationally connected with the section bars between the upper platform and the lower platform, two pushing blocks symmetrically arranged along the guiding sliding 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; the linear bearing sets are fixed on the surface of the lower platform, the two pushing blocks horizontally slide along the two linear bearing sets, 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 guide sliding block respectively, one ends of the two first connecting rods are rotationally connected with two sides of one end of the guide sliding block respectively, one ends of the two second connecting rods are rotationally connected with two sides of the other end of the guide sliding block respectively, the other ends of the two second connecting rods are rotationally connected with two sides of the other end of the guide sliding block respectively, one ends of the two third connecting rods are rotationally connected with one end of the two pushing blocks respectively, one ends of the two fourth connecting rods are rotationally connected with the other ends of the two pushing blocks respectively, and the other ends of the two fourth connecting rods are rotationally connected with two ends of the other linkage block respectively; the rigidity adjusting cylinder is fixed on the surface of the lower platform, the output end of the rigidity adjusting cylinder is fixedly connected with one pushing block, the bending rigidity of the two leaf springs is changed by pushing the pushing block through the rigidity adjusting cylinder, and the rigidity of the translation transmission mechanism is adjusted.

Further, the number of the translational rigidity simulation platforms is not less than two, the platform bottom plate, the platform support plate or the lower platform of each translational rigidity simulation platform is directly stacked on the first guide rail group or the translational guide rail group of the lower translational rigidity simulation platform through an heightening frame or is fixedly connected with the top cone seat of the lower translational rigidity simulation platform, and meanwhile, each translational rigidity simulation platform is connected with the sliding adjusting assembly or the sliding assembly of the lower translational rigidity simulation platform through a transmission shaft, so that the translational rigidity of the upper translational rigidity simulation platform in different movement directions is controlled by the lower translational rigidity simulation platform.

Compared with the prior art, the invention has the following beneficial effects:

The rotation stiffness simulation platform taking the rope drive structure as the core converts rotation of the input end of the flexible base into translation, and realizes real-time variable stiffness adjustment of the rotation direction by matching with a motor in a mode of changing the pretightening force of a spring steel wire rope; and three different translational stiffness simulation platforms based on springs, sliding rails and leaf springs are provided. The rotation and dynamic stiffness simulation platforms are stacked and connected to form the time-varying stiffness base system capable of simultaneously completing rotation stiffness and dynamic stiffness adjustment. The system 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.

Drawings

FIG. 1 is an overall block diagram of a multi-directional motion translating time-varying stiffness base system provided in accordance with particular embodiment 1;

FIG. 2 is a block diagram of a rotational stiffness simulation platform in a multi-directional motion converted time-varying stiffness base system provided in accordance with particular embodiment 1;

FIG. 3 is a top view block diagram of a rotational stiffness simulation platform in a multi-directional motion translating time-varying stiffness base system provided in accordance with particular embodiment 1;

FIG. 4 is a side view block diagram of a rotational stiffness simulation platform in a multi-directional motion translating time-varying stiffness base system provided in accordance with particular embodiment 1;

FIG. 5 is a block diagram of a first translational stiffness simulation platform in a multi-directional motion converted time-varying stiffness base system provided in accordance with example 1;

FIG. 6 is a block diagram of a first translational stiffness varying mechanism in a multi-directional motion translating, time varying stiffness base system provided in accordance with particular embodiment 1;

FIG. 7 is a top view block diagram of a first translational stiffness varying mechanism in a multi-directional motion-converted time varying stiffness base system provided in accordance with example 1;

FIG. 8 is an overall block diagram of a multi-directional motion translating time-varying stiffness base system provided in accordance with particular embodiment 2;

FIG. 9 is a top view block diagram of a third translational stiffness simulation platform in a multi-directional motion converted time-varying stiffness base system provided in accordance with example 2;

FIG. 10 is a block diagram of a variable stiffness adjustment unit in a multi-directional motion translating time-varying stiffness base system provided in accordance with embodiment 2;

FIG. 11 is a cross-sectional block diagram of a variable stiffness adjustment unit in a multi-directional motion translating time-variable stiffness base system provided in accordance with specific embodiment 2;

FIG. 12 is an overall block diagram of a multi-directional motion translating time varying stiffness base system provided in accordance with embodiment 3;

FIG. 13 is a schematic view of a first translational stiffness transfer mechanism in a multi-directional motion translating, time varying stiffness base system according to embodiment 3 coupled with a fifth translational stiffness transfer mechanism at a first viewing angle;

FIG. 14 is a schematic diagram illustrating the cooperation of a first translational motion transfer mechanism and a fifth translational stiffness varying mechanism from a second perspective in a multi-directional motion-converted time-varying stiffness base system according to example 3;

Fig. 15 is a schematic structural diagram of a fifth translational stiffness varying mechanism in a multidirectional motion-converted time-varying stiffness base system according to embodiment 3.

Reference numerals: the input end 1 of a flexible base, a triangle connecting frame 1-1, a connecting hole 1-2, a supporting platform 1-3, a table edge 1-4, a flexible base cover plate 2, a rotation rigidity simulation platform 3, a motion conversion mechanism 3-1, a rotation supporting frame 3-11, a rotation supporting platform 3-111, a rotation supporting arm 3-112, a rotation supporting frame base 3-113, a traction turntable 3-12, a connecting rod 3-13, a motion conversion sliding rail 3-14, a motion conversion sliding block 3-15, a rotation rigidity changing mechanism 3-2, a rotation guide wheel 3-21, a rotation rope receiving wheel 3-22, a belt pulley 3-23, a tensioning wheel 3-24, a rotation rigidity adjusting motor 3-25, a belt 3-26, a supporting base plate 3-3, a rotation platform base plate 3-4, a first rigidity simulation platform 4, a translation the first sliding adjusting component 4-1, the first guide rail group 4-2, the first translational rigidity-changing mechanism 4-3, the circular arc track 4-31, the track rotation center post 4-32, the inscription slide block 4-33, the guiding connecting arm 4-34, the guiding connecting rod 4-35, the pressure spring 4-36, the motor 4-37, the rigidity-adjusting rotation center post 4-38, the bevel gear group 4-39, the linear bearing 4-310, the first platform bottom plate 4-4, the second translational rigidity-changing simulation platform 5, the second platform bottom plate 5-1, the second guide rail group 5-2, the second translational rigidity-changing mechanism 5-3, the spring wire rope 6, the third translational rigidity-changing simulation platform 7, the first platform support plate 7-1, the third guide rail group 7-2, the third translational rigidity-changing mechanism 7-3, the top cone seat 7-31, the rigidity-changing adjusting unit 7-32, the driving motor 7-321, the first coupler 7-322, the ball spline 7-323, the rotating shaft 7-324, the spring 7-325, the pedestal 7-326, the T-shaped base 7-3261, the sleeve 7-3262, the clamping piece 7-327, the clamping cone 7-3271, the clamping cone block 7-3272, the bolt 7-3273, the bearing 7-328, the shaft sleeve 7-329, the end cover 7-330, the top cone 7-33, the fourth translational rigidity-changing mechanism 8-3, the second platform supporting plate 8-1, the fourth guide rail set 8-2, the fourth translational rigidity-changing mechanism 8-3, the fifth rigidity-changing mechanism 9, the first upper platform 9-1, the first lower platform 9-2 the first translational motion transfer mechanism 9-3, the translational motion guide rail group 9-31, the guide shaft 9-32, the guide slide block 9-33, the supporting spring 9-34, the translational motion connecting slide block 9-35, the translational motion slide block 9-36, the translational motion adjusting slide rail 9-37, the fifth translational motion rigidity-changing mechanism 9-4, the rigidity-adjusting cylinder 9-41, the linkage block 9-42, the pushing block 9-43, the linear bearing group 9-44, the leaf spring 9-45, the first connecting rod 9-46, the second connecting rod 9-47, the third connecting rod 9-48, the fourth connecting rod 9-49, the bearing seat 9-410, the sixth rigidity-changing simulation platform 10, the second upper platform 10-1, the second lower platform 10-2, the second translational motion transfer mechanism 10-3 and the sixth rigidity-changing mechanism 10-4, A transmission shaft 11 and a section bar 12.

Detailed Description

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 multidirectional motion conversion time-varying stiffness base systems with different structural designs, wherein each base system can simulate the stiffness change of a large arm as a small arm base in a plurality of degrees of freedom when the combined arms are connected.

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 time-varying rigidity base system for multi-directional movement conversion can simulate the horizontal rotation rigidity change and the two perpendicular translation rigidity changes.

The three multi-directional motion conversion time-varying stiffness base systems adopt base input ends and rotation stiffness simulation platforms with the same structural design, and translational stiffness simulation platforms with different structural designs, and the specific structures of the three active stiffness-varying modularized bases are described in detail below in three embodiments.

Specific example 1:

In the multidirectional motion conversion time-varying stiffness base system provided in the embodiment 1, a rotational stiffness simulation platform based on a rope drive mechanism converts rotation from an input end of a flexible base into translation and performs stiffness adjustment; the translational rigidity simulation platform controls the change of the moment of the translational rigidity-changing mechanism through a motor, adjusts the rigidity of the translational rigidity simulation platform, acts on the input end of the flexible base, and realizes the adjustment of the translational rigidity of the input end of the flexible base.

As shown in fig. 1 to 7, the time-varying stiffness base system for multi-directional motion conversion provided in this embodiment 1 includes a flexible base input end 1, a flexible base cover plate 2, a rotational stiffness simulation platform 3, a first translational stiffness simulation platform 4, and a second translational stiffness simulation platform 5. The flexible base input end 1 is mounted on the top surface of the flexible base cover plate 2, the rotational stiffness simulation platform 3 is fixed on the bottom surface of the flexible base cover plate 2 through a section bar 12, and the first translational stiffness simulation platform 4 is connected with the rotational stiffness simulation platform 3, so that the first translational stiffness simulation platform 4 controls the translational stiffness of the flexible base input end 1 in real time.

In the embodiment 1, the flexible base input end 1 includes a triangle connecting frame 1-1 and a connecting hole 1-2 formed in the triangle connecting frame 1-1, the connecting hole 1-2 is used for being connected with an external power source, and rotation or translation is input to the flexible base input end 1 by the power source so as to simulate rotation of the forearm in the horizontal direction and orthogonal translation in the horizontal direction. The triangular connecting frame 1-1 is arranged on the top surface of the flexible base cover plate 2 through a supporting table 1-3, table edges 1-4 are outwards formed at two ends of the supporting table 1-3, the table edges 1-4 are fixed on the flexible base cover plate 2 through screws, and rolling bearings are arranged at the bottom of the supporting table 1-3.

The rotational stiffness simulation platform 3 comprises a motion conversion mechanism 3-1, a rotational stiffness variation mechanism 3-2 and a supporting bottom plate 3-3. The rotation rigidity-changing mechanism 3-2 is arranged on the supporting bottom plate 3-3, and the motion conversion mechanism 3-1 is connected with the flexible base input end 1 through a coupler and is used for converting the rotation of the flexible base input end 1 into the translation diffused to the periphery; the rotation rigidity-changing mechanism 3-2 coaxially controls the motion conversion mechanism 3-1, and the pretightening force of the rotation rigidity-changing mechanism 3-2 to the motion conversion mechanism 3-1 is controlled in real time, so that the motion rigidity of the motion conversion mechanism 3-1 is controlled.

The motion conversion mechanism 3-1 comprises a rotary support frame 3-11, a traction turntable 3-12, a connecting rod 3-13, a motion conversion slide rail 3-14 and a motion conversion slide block 3-15 matched with the motion conversion slide rail 3-14.

The rotary support frame 3-11 comprises a rotary support table 3-111, a rotary support arm 3-112 and at least two rotary support frame bases 3-113, and the rotary support table 3-111 and the rotary support arm 3-112 are of an integrated structure.

The number of the rotary support arms 3-112 is consistent with that of the rotary support frame bases 3-113, one ends of the rotary support arms 3-112 are uniformly arranged on the circumference of the rotary support table 3-111, and the other ends of the rotary support arms 3-112 are arranged on the rotary support frame bases 3-113, so that the rotary support frame bases 3-113 support the rotary support table 3-111 through the rotary support arms 3-112. The number of the motion conversion slide rails 3-14 is the same as that of the rotary support arms 3-112, and is mounted on the rotary support arms 3-112.

In embodiment 1 of the present invention, the number of the rotary support arms 3 to 112 is 3, and the angle between each two rotary support arms 3 to 112 is 120 °.

The flexible base input end 1 is coaxially connected with the traction turntable 3-12 through a coupler, the motion conversion sliding block 3-15 is connected with the traction turntable 3-12 through a connecting rod 3-13, so that the rotation of the flexible base input end 1 is converted into the translation of the motion conversion sliding block 3-15 on the motion conversion sliding rail 3-14 through the traction turntable 3-12 through the connecting rod 3-13.

The rotary rigidity-changing mechanism 3-2 comprises a rotary guide wheel 3-21, a rotary rope collecting wheel 3-22, a belt pulley 3-23, a tensioning wheel 3-24 and a rotary rigidity-adjusting motor 3-25.

The number of the belt pulleys 3-23 and the tensioning wheels 3-24 is consistent with that of the rotary support frame bases 3-113, the belt pulleys 3-23 are sleeved on the rotary support frame bases 3-113 and lower than the rotary support arms 3-112, and the belt 3-26 sleeved on and connected with the belt pulleys 3-23 is lower than the rotary support arms 3-112; the tensioning wheels 3-24 are in the same height as the belt pulleys 3-23 and are uniformly distributed along the circumferential direction of the rotary supporting table 3-111, so that the tensioning wheels 3-24 press the belt 3-26 towards the rotary supporting table 3-111.

The rotation rigidity-adjusting motor 3-25 is fixed on the supporting bottom plate 3-3, the output end of the rotation rigidity-adjusting motor 3-25 is connected with a worm through a coupler, the worm is meshed with a worm wheel arranged on any belt pulley 3-23, the rotation rigidity-adjusting motor 3-25 controls the rotation of the belt pulley 3-23 through the cooperation of the worm and the worm wheel, and further the rotation of other belt pulleys 3-23 is controlled through a belt 3-26.

The number of the rotating rope collecting wheels 3-22 is consistent with that of the belt pulleys 3-23, and the rotating rope collecting wheels are coaxially arranged on the rotating support frame base 3-113 with the belt pulleys 3-23, so that the belt pulleys 3-23 drive the rotating rope collecting wheels 3-22 to synchronously rotate; the number of the rotary guide wheels 3-21 is consistent with that of the rotary rope collecting wheels 3-22, and the rotary rope collecting wheels 3-22 are arranged on the rotary supporting arm 3-112 near the rotary rope collecting wheels.

The motion conversion sliding block 3-15 is provided with a spring steel wire rope 6 connected with the rotating rope collecting wheel 3-22 on the adjacent rotating support frame base 3-113, and the specific installation mode is that one end of the spring steel wire rope 6 is fixed on the motion conversion sliding block 3-15, and the other end of the spring steel wire rope 6 bypasses the rotating guide wheel 3-21 to be fixed on the rotating rope collecting wheel 3-22 on the adjacent rotating support frame base 3-113.

When the flexible base input end 1 drives the traction turntable 3-12 to rotate through the coupler, the rotation of the traction turntable 3-12 is converted into linear motion of the motion conversion sliding block 3-15 along the motion conversion sliding rail 3-14 through the connecting rod 3-13. When the rotation rigidity adjusting motor 3-25 is started, the rotation rigidity adjusting motor 3-25 drives the worm wheel and the worm to rotate through the coupler, so that the belt pulley 3-23 is driven, the rotation rope collecting wheels 3-22 are further caused to be linked, the rotation rope collecting wheels 3-22 tighten the spring steel wire ropes 6, the pretightening force of the spring steel wire ropes 6 is further changed, and therefore the rotation rigidity of the traction turntable 3-12 is changed, and the rotation rigidity of the flexible base input end 1 is controllable and time-varying.

The first translational rigidity simulation platform 4 comprises a first sliding adjusting assembly 4-1, two first guide rail groups 4-2, a first platform bottom plate 4-4 and a first translational rigidity changing mechanism 4-3. In embodiment 1, the number of the first translational rigidity-varying mechanisms 4-3 is two.

The second dynamic stiffness simulation platform 5 comprises a second sliding adjusting component, a second platform bottom plate 5-1, two second guide rail groups 5-2 and a second dynamic stiffness changing mechanism 5-3. In embodiment 1, the number of the second translational rigidity changing mechanisms 5-3 is also two.

The first guide rail group 4-2, the first sliding adjusting assembly 4-1 and the first translational rigidity-changing mechanism 4-3 are all installed on the first platform bottom plate 4-4, the two first translational rigidity-changing mechanisms 4-3 are respectively located at two ends of the first sliding adjusting assembly 4-1 and are all in contact with the first sliding adjusting assembly 4-1, and the translational rigidity of the supporting bottom plate 3-3 is adjusted in real time through the first sliding adjusting assembly 4-1 and the transmission shaft 11 by the two first translational rigidity-changing mechanisms 4-3. The two first guide rail groups 4-2 are parallel to the first sliding adjusting assembly 4-1 and fixed at both ends of the first platform base plate 4-4, and the supporting base plate 3-3 is moved on the first guide rail groups 4-2 by the height increasing frame. The connection and installation modes of the second sliding adjusting assembly, the second platform bottom plate 5-1, the second guide rail group 5-2 and the second translational rigidity-changing mechanism 5-3 are the same as above, and are not repeated here.

The first sliding adjusting component 4-1 comprises a connecting slide block and a translational slide rail, the translational slide rail is fixed on the platform bottom plate 4-4, the transmission shaft 11 is fixed on the connecting slide block, a roller which is tightly contacted with the first translational rigidity-changing mechanism 4-3 is sleeved on the transmission shaft 11, and when the transmission shaft 11 drives the connecting slide block to translate on the translational slide rail, the roller on the connecting slide block rolls and extrudes the first translational rigidity-changing mechanism 4-3 to rotate.

The first guide rail group 4-2 comprises a translation guide rail and a translation sliding block, and the translation guide rail is parallel to the translation guide rail and is fixed at two ends of the platform bottom plate. The supporting bottom plate 3-3 is arranged on the translation sliding block through the heightening frame, so that the translation sliding block is matched with the translation guide rail to drive the supporting bottom plate 3-3 to translate.

The first translational rigidity-changing mechanism 4-3 comprises an arc track 4-31, a track rotation center column 4-32, an inscription slider 4-33, a guiding connecting arm 4-34, a guiding connecting rod 4-35, a pressure spring 4-36, a motor 4-37, a rigidity-adjusting rotation center column 4-38, a bevel gear set 4-39 and a linear bearing 4-310.

Wherein, the track gyration center post 4-32 is fixed on first platform bottom plate 4-4, and the gyro wheel that the cover was established on the transmission shaft 11 is closely contacted to the one end of circular arc track 4-31, and the other end and the track gyration center post 4-32 fixed connection of circular arc track 4-31. When the transmission shaft 11 and the rollers thereof translate along the translation sliding rail, the rollers squeeze the circular arc tracks 4-31, so that the circular arc tracks 4-31 rotate by the track rotation center column 4-32.

The rigid adjusting rotary center column 4-38 and the motor 4-37 are arranged on the first platform bottom plate 4-4, the bevel gear set 4-39 is arranged on the rigid adjusting rotary center column 4-38, the output end of the motor 4-37 is fixedly connected with a driving bevel gear in the bevel gear set 4-39, and the driving bevel gear is matched with a driven bevel gear in the bevel gear set 4-39, so that the motor 4-37 drives the output end of the rigid adjusting rotary center column 4-38 to rotate through the bevel gear set 4-39.

The fixed end of the guiding connecting arm 4-34 is fixedly connected with the output end of the rigid adjusting rotation center column 4-38, and the movable end of the guiding connecting arm 4-34 is provided with a mounting piece for mounting the guiding connecting rod 4-35. The guide rod of the linear bearing 4-310 is fixed on the guide connecting arm 4-34, and the bearing of the linear bearing 4-310 is connected with the guide connecting rod 4-35, so that the guide connecting rod 4-35 moves along the direction of the linear bearing 4-310.

The installation side of the inscription slider 4-33 is arranged on the guide connecting rod 4-35, and the movable side of the inscription slider 4-33 is matched with the inner wall of the circular arc track 4-31, so that the inscription slider 4-33 drives the guide connecting rod 4-35 to move along the inner wall of the circular arc track 4-31. One end of the pressure spring 4-36 is fixed on the fixed end of the guiding connecting arm 4-34, and the other end of the pressure spring 4-36 is connected with the guiding connecting rod 4-35.

The first sliding adjusting means 4-1 always maintains contact with the circular arc rail 4-31 while moving along the guide rail. The resistance force applied to the movement of the first sliding adjusting member 4-1 counteracts the circular arc rail 4-31, causing the circular arc rail 4-31 to rotate about the rail revolution center post 4-32, in which process the resistance force is transmitted to the compression spring 4-36 via the inscribed slider 4-33 and the guide link 4-35. The compression spring 4-36 is extruded to generate elastic force, and in order to balance moment, the motor 4-37 drives the bevel gear set 4-39 to drive the inscription slide block 4-33, the guide connecting rod 4-35, the compression spring 4-36 and the linear bearing 4-310 to rotate around the rigid rotation center column 4-38. By changing the elastic force moment in real time, the rigidity of the first translational rigidity-changing mechanism 4-3 in the movement direction is controllable and time-varying.

The first platform bottom plate 4-4 is mounted on the second guide rail group 5-2 of the second translational rigidity simulation platform 5, and meanwhile, the first platform bottom plate 4-4 is connected with the second sliding adjusting assembly through the transmission shaft 11, so that the second translational rigidity simulation platform 5 controls the translational rigidity of the first translational rigidity simulation platform 4 in the other translational direction.

According to the multidirectional motion conversion time-varying stiffness base system provided by the embodiment 1, the rotation of the flexible base input end 1 is converted into the translation of the conversion sliding blocks 3-15 through the rotation stiffness simulation platform 3, and the pretightening force of the spring steel wire rope 6 on the conversion sliding blocks is changed, so that the rotation stiffness of the flexible base input end 1 is controllable and time-varying; the two vertical translational motions of the flexible base input end 1 are converted into the translational motions of the sliding block assembly through the first translational motion stiffness simulation platform 4 and the second translational motion stiffness simulation platform 5, and the translational motion stiffness of the flexible base input end 1 is controllable and time-varying through changing the moment of the pressure springs 4-36. In this way, the stiffness of the large arm, which is used as a base of the small arm during the movement of the large arm, is simulated and changed in real time during the movement.

Specific example 2:

in the multidirectional motion conversion time-varying stiffness base system provided in this embodiment 2, a rotational stiffness simulation platform based on a rope drive mechanism converts rotation from an input end of a flexible base into translation and performs stiffness adjustment; the translational stiffness simulation platform adjusts the self stiffness by changing the effective number of turns of the spring and acts on the input end of the flexible base, so that the translational stiffness of the input end of the flexible base is adjusted.

As shown in fig. 8 to 11, the time-varying stiffness base system for multi-directional motion conversion provided in this embodiment 2 includes a flexible base input end 1, a flexible base cover plate 2, a rotational stiffness simulation platform 3, a third translational stiffness simulation platform 7, and a fourth translational stiffness simulation platform 8.

The installation connection manner of the flexible base input end 1, the flexible base cover plate 2 and the rotational stiffness simulation platform 3 is consistent with the time-varying stiffness base system for multi-directional motion conversion provided in this embodiment 1, and will not be described herein. And the rotational stiffness simulation platform 3 in the multidirectional motion converted time-varying stiffness base system provided by the embodiment 2 and the rotational stiffness simulation platform 3 in the multidirectional motion converted time-varying stiffness base system provided by the embodiment 1 comprise a motion conversion mechanism 3-1, a rotational stiffness conversion mechanism 3-2 and a supporting base plate 3-3 which are in a consistent structure, and a rotational platform base plate 3-4 is installed at the bottom of the supporting base plate 3-3 through a section bar 12. The third translational rigidity simulation platform 7 is connected with the section bar 12 between the supporting bottom plate 3-3 and the rotating platform bottom plate 3-4, so as to control the integral translational rigidity of the rotating rigidity simulation platform 3.

The third translational rigidity simulation platform 7 comprises a first platform supporting plate 7-1, a third guide rail group 7-2 and a third translational rigidity-changing mechanism 7-3, wherein a guide bearing piece of the third guide rail group 7-2 is arranged on the first platform supporting plate 7-1, a moving piece of the third guide rail group 7-2 is fixedly connected with the bottom of the rotating platform bottom plate 3-4, and the third translational rigidity-changing mechanism 7-3 is used for adjusting the rigidity of the third translational rigidity-changing mechanism by changing the effective number of turns of a spring so as to change the translational rigidity of the input end 1 of the flexible base in one horizontal direction; the fourth translational rigidity simulation platform 8 comprises a second platform supporting plate 8-1, a fourth guide rail group 8-2 and a fourth translational rigidity-changing mechanism 8-3, wherein the fourth guide rail group 8-2 is arranged on the second platform supporting plate 8-1, the fourth guide rail group 8-2 and the third guide rail group 7-2 are orthogonally arranged, namely, the moving directions of the fourth guide rail group 8-2 and the third guide rail group 7-2 are perpendicular, a moving piece of the fourth guide rail group 8-2 is fixedly connected with the bottom of the first platform supporting plate 7-1, and the fourth translational rigidity-changing mechanism 8-3 is used for adjusting the rigidity of the fourth translational rigidity-changing mechanism by changing the effective number of turns of a spring so as to change the rigidity translation of the other horizontal direction of the input end 1 of the flexible base.

The third translational rigidity-changing mechanism 7-3 comprises a top cone seat 7-31 and two rigidity-changing adjusting units 7-32 with the same structure, wherein top cone holes are respectively processed on two opposite surfaces of the top cone seat 7-31 and are used for installing the top cones 7-33, the two rigidity-changing adjusting units 7-32 are respectively abutted with the two top cones 7-33, and the top cone seat 7-31 is fixed on a section bar 12 between the supporting bottom plate 3-3 and the rotating platform bottom plate 3-4, so that the rotating platform bottom plate 3-4 is subjected to acting force in two directions, namely the translational movement of the rotating platform bottom plate 3-4 is interfered by the two rigidity-changing adjusting units 7-32. The translational rigidity of the input end 1 of the flexible base is controllable and time-varying by changing the output rigidity of the rigidity-varying adjusting units 7-32 in real time.

The rigidity-changing adjusting unit 7-32 comprises a driving motor 7-321, a first coupling 7-322, a ball spline 7-323, a rotating shaft 7-324, a spring 7-325, a pedestal 7-326, a clamping piece 7-327, a bearing 7-328, a shaft sleeve 7-329 and an end cover 7-330.

The driving motor 7-321 is fixed on the first platform supporting plate 7-1 through a motor bracket, an output shaft of the driving motor 7-321 is connected with a spline shaft of a ball spline 7-323 through a first coupler 7-322, a flange of the ball spline 7-323 is connected with a rotating shaft 7-324, a shaft sleeve 7-329 is sleeved at the end part of the rotating shaft 7-324, a spring 7-325 and a bearing 7-328 are respectively sleeved at two ends of the shaft sleeve 7-329, an end cover 7-330 is sleeved on the shaft sleeve 7-329 and is positioned at the outer side of the spring 7-325 and the bearing 7-328, the end cover 7-330 is abutted against a tip cone 7-33, an inner ring of the bearing 7-328 is contacted with the shaft sleeve 7-329, and an outer ring of the bearing 7-328 is contacted with the end cover 7-330; the pedestal 7-326 comprises a T-shaped base 7-3261 and a sleeve 7-3262 which are of an integral structure or a split structure, the T-shaped base 7-3261 is fixedly arranged on the first platform supporting plate 7-1 through two L-shaped connecting blocks, the sleeve 7-3262 is supported and fixed, and the sleeve 7-3262 is sleeved on the outer side of the spring 7-325; the clamping piece 7-327 comprises a clamping cone 7-3271 and a clamping cone block 7-3272 which are of an integral structure or a split structure, wherein the clamping cone block 7-3272 is fixed on the outer side of the sleeve 7-3262 through a bolt 7-3273, and the clamping cone 7-3271 passes through the sleeve 7-3262 and then is clamped into the spring 7-325; the output shaft of the driving motor 7-321 is controlled to rotate, the output shaft is sequentially transmitted to the spring 7-325 through the first coupler 7-322, the ball spline 7-323, the rotating shaft 7-324 and the shaft sleeve 7-329, the spring 7-325 abuts against the clamping cone 7-3271 to rotate along the radial direction, so that the effective number of turns of the spring 7-325 is changed, and the time-varying rigidity output of the end cover 7-330 to the top cone seat 7-31 is realized.

In order to adjust the position of the clamping cone 7-3271, waist-shaped holes for adjusting the position of the bolt 7-3273 are respectively formed in the clamping cone block 7-3272 and the sleeve 7-3262, an avoidance hole is formed in the sleeve 7-3262, and the clamping cone 7-3271 passes through the avoidance hole downwards and then is clamped into the spring 7-325.

Alternatively, the clamping piece 7-327 can be a bolt, an adjusting hole is formed in the sleeve 7-3262, the head of the bolt is clamped at the outer side of the adjusting hole, the screw rod of the bolt passes through the adjusting hole downwards and then is clamped into the spring 7-325, and the screw rod is locked on the sleeve 7-3262 through a nut.

The fourth translational rigidity simulation platform 8 comprises a second platform supporting plate 8-1, a fourth guide rail set 8-2 and a fourth translational rigidity changing mechanism 8-3, and the connection and installation mode is consistent with the structure of the third translational rigidity simulation platform 7, so that the description is omitted here. The top cone seat 7-31 of the third translational rigidity-changing mechanism 7-3 is fixed on the section bar 12 between the supporting bottom plate 3-3 and the rotating platform bottom plate 3-4, and the top cone seat of the fourth translational rigidity simulation platform 8 is fixed on the first platform supporting plate 7-1.

According to the multidirectional motion conversion time-varying stiffness base system provided by the embodiment 2, the rotation of the flexible base input end 1 is converted into the translation of the conversion sliding blocks 3-15 through the rotation stiffness simulation platform 3, and the pretightening force of the spring steel wire rope 6 on the conversion sliding blocks is changed, so that the rotation stiffness of the flexible base input end 1 is controllable and time-varying; the translational motions in the two vertical directions of the flexible base input end 1 are converted into the translational motions of the top cone seat 7-31 through the third translational motion stiffness simulation platform 7 and the fourth translational motion stiffness simulation platform 8, and the effective number of turns used for outputting the stiffness in the springs 7-325 is changed, so that the translational stiffness of the flexible base input end 1 is controllable and time-varying. In this way, the stiffness of the large arm, which is used as a base of the small arm during the movement of the large arm, is simulated and changed in real time during the movement.

Specific example 3:

In the multidirectional motion conversion time-varying stiffness base system provided in this embodiment 3, the rotation stiffness simulation platform based on the rope drive mechanism converts rotation from the input end of the flexible base into translation and performs stiffness adjustment; the translational stiffness simulation platform adjusts the self stiffness by changing the stiffness of the leaf spring and acts on the input end of the flexible base to realize the adjustment of the translational stiffness of the input end of the flexible base.

As shown in fig. 12 to 15, the time-varying stiffness base system for multi-directional motion conversion provided in this embodiment 3 includes a flexible base input end 1, a flexible base cover plate 2, a rotational stiffness simulation platform 3, a fifth translational stiffness simulation platform 9, and a sixth translational stiffness simulation platform 10.

The installation connection manner of the flexible base input end 1, the flexible base cover plate 2 and the rotational stiffness simulation platform 3 is consistent with the time-varying stiffness base system for multi-directional motion conversion provided in embodiment 1, and will not be described herein. And the rotational stiffness simulation platform 3 in the multi-directional motion converted time-varying stiffness base system provided by the embodiment 3 and the rotational stiffness simulation platform 3 in the multi-directional motion converted time-varying stiffness base system provided by the embodiment 1 comprise a motion conversion mechanism 3-1, a rotational stiffness conversion mechanism 3-2 and a supporting bottom plate 3-3 which are in a consistent structure, and the fifth translational stiffness simulation platform 9 is connected with the supporting bottom plate 3-3 through a transmission shaft 11 and controls the overall translational stiffness of the rotational stiffness simulation platform 3.

The fifth translational rigidity simulation platform 9 comprises a first upper platform 9-1, a first lower platform 9-2, a first translational transmission mechanism 9-3 and a fifth translational rigidity-changing mechanism 9-4, wherein a translational guide rail group 9-31 in the first translational transmission mechanism 9-3 is fixed on the first upper platform 9-1, the translational movement input by the flexible base input end 1 is transmitted to the first translational transmission mechanism 9-3, and the fifth translational rigidity-changing mechanism 9-4 is fixed on the first lower platform 9-2 and connected with the first translational transmission mechanism 9-3 for adjusting the rigidity of the first translational transmission mechanism 9-3 by changing the rigidity of a leaf spring, so that the translational rigidity of the flexible base input end 1 is adjusted. The sixth translational rigidity simulation platform 10 comprises a second upper platform 10-1, a second lower platform 10-2, a second translational transmission mechanism 10-3 and a sixth translational rigidity-changing mechanism 10-4, wherein the translational rigidity of the other vertical direction of the flexible base input end 1 is transmitted to the second translational transmission mechanism 10-3, the fifth translational rigidity simulation platform 9 is carried on the second upper platform 10-1, and the sixth translational rigidity-changing mechanism 10-4 is fixed on the second lower platform 10-2 and is connected with the second translational transmission mechanism 10-3. The installation mode of the sixth translational rigidity simulation platform 10 is consistent with that of the fifth translational rigidity simulation platform 9, so that description thereof is omitted.

The first upper platform 9-1 is in supporting connection with the first lower platform 9-2 through a section bar 12.

The first translational transfer mechanism 9-3 includes a translational guide rail set 9-31, a guide shaft 9-32, a guide slider 9-33, a support spring 9-34, and a slide assembly. The bearing guide piece of the translation guide rail group 9-31 is fixed on the surface of the first upper platform 9-1, and the moving piece of the translation guide rail group 9-31 is fixedly connected with the bottom surface of the supporting bottom plate 3-3; the sliding component comprises translation connecting sliding blocks 9-35, translation sliding blocks 9-36 and translation adjusting sliding rails 9-37, wherein the translation adjusting sliding rails 9-37 are arranged in parallel with the translation guide rail group 9-31, the number of the translation sliding blocks 9-36 is two and distributed on two sides of the translation connecting sliding blocks 9-35, the two translation sliding blocks 9-36 and the translation connecting sliding blocks 9-35 form a sliding block group, and the sliding blocks linearly slide on the translation adjusting sliding rails 9-37; one end of the transmission shaft 11 is fixed with the translational connecting sliding block 9-35, the other end of the transmission shaft 11 is fixedly connected with the supporting bottom plate 3-3, one end of the supporting spring 9-34 is fixedly connected with the first lower platform 9-2, the other end of the supporting spring 9-32 is fixedly connected with the bottom of the first upper platform 9-1, a screw downwards passes through the translational adjusting sliding rail 9-37 and the first upper platform 9-1 and then is connected with the upper end of the supporting shaft 9-32, the fixed connection of the three is realized, the supporting sliding block 9-33 is sleeved on the supporting shaft 9-32 and slides up and down along the supporting shaft 9-32, the supporting spring 9-34 is sleeved on the supporting shaft 9-32, one end of the supporting spring 9-34 is abutted with the bottom of the supporting sliding block 9-33, the other end of the supporting spring 9-34 is abutted with the first lower platform 9-2, and the supporting spring 9-34 provides a force opposite to the moving direction of the supporting sliding block 9-33.

The fifth translational rigidity-changing mechanism 9-4 comprises a rigidity-adjusting cylinder 9-41, two linkage blocks 9-42 rotationally connected with the section bar 12, two pushing blocks 9-43 symmetrically arranged along the guiding sliding block 9-33, two linear bearing groups 9-44, two leaf springs 9-45, two first connecting rods 9-46, two second connecting rods 9-47, two third connecting rods 9-48 and two fourth connecting rods 9-49, bearing seats 9-410 are respectively arranged on the section bar 12 and the linkage blocks 9-42, bearings are arranged between the two bearing seats 9-410 to realize the rotation of the linkage blocks 9-42 relative to the section bar 12, the two pushing blocks 9-43 horizontally slide along the two linear bearing groups 9-44, one ends of the two leaf springs 9-45 are respectively fixedly connected with the two pushing blocks 9-43, the other ends of the two leaf springs 9-45 are respectively and fixedly connected with two sides of the guide slide block 9-33, one ends of the two first connecting rods 9-46 are respectively and rotatably connected with two sides of one translation slide block 9-36, the other ends of the two first connecting rods 9-46 are respectively and rotatably connected with two sides of one end of the guide slide block 9-33, one ends of the two second connecting rods 9-47 are respectively and rotatably connected with two sides of the other end of the guide slide block 9-33, the other ends of the two second connecting rods 9-47 are respectively and rotatably connected with two sides of the other end of the guide slide block 9-33, one ends of the two third connecting rods 9-48 are respectively and rotatably connected with one end of the pushing block 9-43, the other ends of the two third connecting rods 9-48 are respectively and rotatably connected with two ends of the one linkage block 9-42, one end of each of the two fourth connecting rods 9-49 is respectively and rotatably connected with the other end of each of the two pushing blocks 9-43, the other end of each of the two fourth connecting rods 9-49 is respectively and rotatably connected with two ends of the other linkage block 9-42, and the output end of the rigidity adjusting cylinder 9-41 is fixedly connected with one of the pushing blocks 9-43.

The translation of the flexible base input end 1 in the direction of the translation guide rail group 9-31 is transmitted to the sliding component through the supporting bottom plate 3-3 and the transmission shaft 11, so that the sliding block group moves linearly along the translation adjusting guide rail 9-37, and the linear motion of the sliding block group is converted into the vertical linear motion of the guide sliding block 9-33 through the first connecting rod 9-46 and the second connecting rod 9-47. The movement of the guide slider 9-33 is disturbed by the leaf spring 9-45 and the support spring 9-34. Wherein the leaf springs 9-45 are formed of two symmetrically stacked spring steel sheets, and a cavity is formed between the two spring steel sheets. The stiffness of the leaf springs 9-45 is related to the width of the cavity, the larger the width of the cavity, the greater the bending stiffness of the leaf springs 9-45 and the greater the resistance to deformation. Therefore, the output rigidity of the fifth translational rigidity-changing mechanism 9-4 can be changed by changing the width of the cavity, so that the rigidity of the first translational transmission mechanism 9-3 and the second translational transmission mechanism 10-3 can be adjusted, and the translational rigidity of the flexible base input end 1 can be adjusted.

The rigid adjusting cylinder 9-41 drives the pushing block 9-43 to slide on the linear bearing group 9-44, and the pushing block 9-43 on the other side synchronously moves through the two linkage blocks 9-42 and the third connecting rod 9-48 and the fourth connecting rod 9-49 on the two sides of the two linkage blocks 9-42, and the movement of the pushing block 9-43 can squeeze the leaf spring 9-45, so that the width of a cavity of the leaf spring 9-45 is changed. By changing the width of the cavities of the leaf springs 9-45 in real time, the stiffness of the slider assembly in the direction of movement is controllable and time-varying.

The principle of rigidity adjustment of the sixth translational rigidity simulation platform 10 is the same as that of the fifth translational rigidity simulation platform 9, so that description is omitted, the translational guide rail set, the sliding assembly of the sixth translational rigidity simulation platform 10, the translational guide rail set 9-31 of the fifth translational rigidity simulation platform 9 and the sliding assembly are arranged in an orthogonal mode, that is, the sliding assembly of the sixth translational rigidity simulation platform 10 is orthogonal to the movement direction of the fifth translational rigidity simulation platform 9, the sliding assembly of the sixth translational rigidity simulation platform 10 is fixedly connected with the first lower platform 9-2 of the fifth translational rigidity simulation platform 9 through the transmission shaft 11, and the translational guide rail set of the sixth translational rigidity simulation platform 10 is connected with the second upper platform 10-1 and the first lower platform 9-2 of the fifth translational rigidity simulation platform 9.

The translation of the flexible base input end 1 in the direction of the translation guide rail group in the second translation transmission mechanism 10-3 is transmitted to the transmission shaft 11 of the sixth translation rigidity simulation platform 10 through the first upper platform 9-1 and the first lower platform 9-2 of the fifth translation rigidity simulation platform 9, and then transmitted to the sliding component of the sixth translation rigidity simulation platform 10.

According to the multi-directional motion conversion time-varying stiffness base system provided by the embodiment 3, the rotation of the flexible base input end 1 is converted into the translation of the conversion sliding blocks 3-15 through the rotation stiffness simulation platform 3, and the pretightening force of the spring steel wire rope 6 on the conversion sliding blocks is changed, so that the rotation stiffness of the flexible base input end 1 is controllable and time-varying; the translational rigidity of the flexible base input end 1 in two vertical directions is converted into the vertical linear motion of the guide sliding block through the fifth translational rigidity simulation platform 9 and the sixth translational rigidity simulation platform 10, and the translational rigidity of the flexible base input end 1 is controllable and time-varying through changing the supporting rigidity of the leaf springs 9-45. In this way, the stiffness of the large arm, which is used as a base of the small arm during the movement of the large arm, is simulated and changed in real time during the movement.

It should be appreciated that various forms of the flows shown above may be used to reorder, add, or delete steps. For example, the steps described in the present disclosure may be performed in parallel, sequentially, or in a different order, provided that the desired results of the technical solutions of the present disclosure are achieved, and are not limited herein.

The above embodiments do not limit the scope of the present invention. It will be apparent to those skilled in the art that various modifications, combinations, sub-combinations and alternatives are possible, depending on design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of the present invention.

Claims

1. The time-varying rigidity base system for multi-directional motion conversion comprises a flexible base input end and a flexible base cover plate, and is characterized by further comprising a rotational rigidity simulation platform and a translational rigidity simulation platform; wherein,

The flexible base input end is mounted to the top surface of the flexible base cover plate through a supporting table; the rotational stiffness simulation platform is connected with the bottom surface of the flexible base cover plate through a section bar; the translational rigidity simulation platform is connected with the rotational rigidity simulation platform through a transmission shaft;

The rotating stiffness simulation platform comprises a motion conversion mechanism and a rotating stiffness variation mechanism; the motion conversion mechanism is connected with the input end of the flexible base through a coupler and is used for converting rotation of the input end of the flexible base into translation diffused to the periphery; the rotation rigidity-changing mechanism coaxially controls the motion conversion mechanism, and the pre-tightening force of the rotation rigidity-changing mechanism on the motion conversion mechanism is controlled in real time, so that the motion rigidity of the motion conversion mechanism is controlled;

the translational rigidity simulation platform comprises a first translational rigidity-changing mechanism, a first guide rail group, a sliding adjusting assembly and a platform bottom plate, wherein the number of the first translational rigidity-changing mechanisms is not less than one, the sliding adjusting assembly and the first translational rigidity-changing mechanism are both arranged on the platform bottom plate, and the translational rigidity of the rotational rigidity simulation platform is adjusted in real time through the sliding adjusting assembly and the transmission shaft; the first guide rail group is parallel to the sliding adjusting assembly and fixed at two ends of the platform bottom plate, and the rotating rigidity simulation platform moves on the first guide rail group through the heightening frame;

or the translational rigidity simulation platform comprises a platform supporting plate, a second guide rail group and a second translational rigidity-changing mechanism, wherein the second guide rail group carries the rotational rigidity-changing mechanism, and the second translational rigidity-changing mechanism is used for adjusting the self rigidity by changing the effective number of turns of a spring so as to change the translational rigidity of the input end of the flexible base;

or the translational rigidity simulation platform comprises an upper platform, a lower platform, a translational transmission mechanism and a third translational rigidity-changing mechanism, wherein the translational transmission mechanism is connected with the rotational rigidity simulation platform through a transmission shaft and is used for transmitting the translational input by the input end of the flexible base to the translational transmission mechanism; the upper platform is connected with the lower platform through a section bar support, and the third translational rigidity-changing mechanism is fixed on the lower platform and connected with the translational transmission mechanism and is used for adjusting the rigidity of the translational transmission mechanism by changing the rigidity of the elastic sheet spring, so that the translational rigidity of the input end of the flexible base is adjusted.

2. The multi-directional motion translating, time varying stiffness base system of claim 1, wherein the rotational stiffness simulation platform further comprises a support floor; wherein the supporting bottom plate is fixed on the bottom surface of the flexible base cover plate through the sectional material; the motion conversion mechanism is arranged on the supporting bottom plate; the rotary rigidity-changing mechanism is arranged on the supporting bottom plate through a supporting block; the supporting bottom plate is arranged on the translational rigidity simulation platform and is connected with the translational rigidity simulation platform through the transmission shaft.

3. The multi-directional motion translating, time varying stiffness base system of claim 2 wherein the motion translating mechanism comprises a rotating support frame, a traction turntable, a linkage, and a motion translating slide mated with the motion translating slide; wherein,

The rotary support frame comprises a rotary support table, a rotary support arm and at least two rotary support frame bases, and the rotary support table and the rotary support arm are of an integrated structure; the number of the rotary support arms is consistent with that of the rotary support frame bases, one ends of the rotary support arms are uniformly arranged on the circumference of the rotary support table, and the other ends of the rotary support arms are arranged on the rotary support frame bases, so that the rotary support frame bases lift the rotary support table through the rotary support arms;

The motion conversion sliding rails are consistent with the rotating supporting arms in number and are arranged on the rotating supporting arms; the flexible base input end is coaxially connected with the traction rotary table through a coupler, the motion conversion sliding block is connected with the traction rotary table through a connecting rod, so that rotation of the flexible base input end is converted into translation of the motion conversion sliding block on the motion conversion sliding rail through the traction rotary table through the connecting rod.

4. The multi-directional motion translating, time varying stiffness base system of claim 3 wherein the rotational stiffness varying mechanism comprises a rotational guide wheel, a rotational sheave, a pulley, a tensioner, and a rotational stiffening motor; wherein,

The number of the belt pulleys and the tension pulleys is consistent with that of the rotating support frame bases, the belt pulleys are sleeved on the rotating support frame bases and lower than the rotating support arms, and the belt sleeved on and connected with the belt pulleys is lower than the rotating support arms; the tensioning wheels are consistent in height with the belt pulleys and are uniformly distributed along the circumferential direction of the rotating supporting table, so that the belt is tightly pressed by the tensioning wheels towards the rotating supporting table;

The rotating rigidity-adjusting motor is fixed on the supporting bottom plate, the output end of the rotating rigidity-adjusting motor is connected with a worm through a coupler, the worm is meshed with a worm wheel arranged on any belt pulley, the rotating rigidity-adjusting motor controls the rotation of the belt pulley through the cooperation of the worm and the worm wheel, and further controls the rotation of other belt pulleys through the belt;

The number of the rotating rope collecting wheels is consistent with that of the belt pulleys, and the rotating rope collecting wheels and the belt pulleys are coaxially arranged on the base of the rotating support frame, so that the belt pulleys drive the rotating rope collecting wheels to synchronously rotate; the number of the rotating guide wheels is consistent with that of the rotating rope winding wheels, and the rotating guide wheels are installed on the rotating support arm close to the rotating rope winding wheels;

The motion conversion sliding block is fixedly provided with a spring steel wire rope connected with a rotating rope collecting wheel on an adjacent rotating support frame base, and the rotating rigidity adjusting motor adjusts the pretightening force of the spring steel wire rope through the belt pulley and the rotating rope collecting wheel so as to adjust the rotating rigidity of the input end of the flexible base.

5. A multi-directional motion translating, time varying stiffness base system according to claim 3 wherein the number of first translational stiffness varying mechanisms is not less than one, each group comprising two first translational stiffness varying mechanisms; the number of the sliding adjusting assemblies is consistent with the number of the groups of the first translational rigidity-changing mechanisms, and each group of the first translational rigidity-changing mechanisms is respectively positioned at two ends of the sliding adjusting assembly and is in close contact with the sliding adjusting assembly, so that the translational rigidity of the rotational rigidity simulation platform is adjusted in real time by the two first translational rigidity-changing mechanisms through the transmission shaft and the sliding adjusting assembly; the two first guide rail groups are parallel to the sliding adjusting assembly and fixed at two ends of the platform bottom plate, and the supporting bottom plate moves on the first guide rail groups through the heightening frame.

6. The multi-directional motion translating, time varying stiffness base system of claim 5, wherein the first translational stiffness varying mechanism comprises a circular arc track, a track revolution center column, an inscribed slider, a guide link, a compression spring, a motor, a stiffening revolution center column, a bevel gear set, and a linear bearing; wherein,

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

The rigidity-adjusting rotation center column and the motor are arranged on the platform bottom plate, the bevel gear group is sleeved on the rigidity-adjusting rotation center column, the output end of the motor is fixedly connected with a driving bevel gear in the bevel gear group, and the driving bevel gear is matched with a driven bevel gear in the bevel gear group, so that the motor drives the output end of the rigidity-adjusting rotation center column to rotate through the bevel gear group;

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 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 motor can control the rigid adjusting rotation center column to complete moment adjustment of the pressure spring in real time, and the rigid adjusting rotation center column is matched with expansion and contraction of the pressure spring, so that the translation rigidity of the input end of the base can be adjusted in real time by the sliding adjusting assembly.

7. The multi-directional motion translating, time varying stiffness base system of claim 6 wherein the sliding adjustment assembly comprises a connecting slide and a translational slide rail, the translational slide rail is fixed to the platform floor, the drive shaft is fixed to the connecting slide block, rollers are sleeved on the drive shaft, one end of the circular arc rail is in close contact with the rollers, and when the drive shaft drives the connecting slide block to translate on the translational slide rail, the rollers roll and squeeze the circular arc rail to rotate around the rail revolution center column.

8. The multi-directional motion converted time-varying stiffness base system according to claim 2, wherein the second translational stiffness mechanism comprises a top cone seat and two stiffness varying adjusting units, the two stiffness varying adjusting units are respectively propped to two sides of the top cone seat through a top cone, the top cone seat is connected with the supporting bottom plate through a profile, and the two stiffness varying adjusting units control the translational stiffness of the rotational stiffness simulation platform through the top cone seat and the profile;

the two rigidity-changing adjusting units comprise a driving motor, a first coupling, ball splines, a rotating shaft, springs, a pedestal, clamping pieces, bearings, shaft sleeves and end covers, wherein the driving motor is fixed on a platform supporting plate, an output shaft of the driving motor is connected with a spline shaft of the ball splines through the first coupling, a flange of the ball splines is 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 on the end covers and the top cone seats;

The pedestal comprises a T-shaped base and a sleeve, the T-shaped base is installed on the platform supporting plate 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 driving motor is controlled, the rotation of the output shaft of the driving motor is sequentially transmitted to the spring through a first coupler, a ball spline, a rotating shaft and a shaft sleeve, 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 achieved.

9. The multi-directional motion translating, time varying stiffness base system of claim 2 wherein the translational transfer mechanism comprises a translational guide set, a slide 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 upper platform, and the moving piece of the translation guide rail group is fixedly connected with the supporting bottom plate; the sliding assembly comprises translational connecting sliding blocks, translational sliding blocks and translational adjusting sliding rails, the translational adjusting sliding rails are arranged in parallel with the translational guide rail group, the number of the translational sliding blocks is two and distributed on two sides of the translational connecting sliding blocks, and the two translational sliding blocks and the translational connecting sliding blocks linearly slide on the translational adjusting sliding rails; one end of the transmission shaft is fixed with the translational connecting sliding block, and the other end of the transmission shaft is fixedly connected with the supporting bottom plate; one end of the guide shaft is fixedly connected with the lower platform, the other end of the guide shaft is fixedly connected with the bottom of the upper platform, and the guide shaft is connected with the upper end of the guide shaft after downwards penetrating through the translational adjustment slide rail and the upper platform through screws, so that the translational adjustment slide rail, the upper platform and the guide shaft are fixedly connected; the guide sliding block is sleeved on the guide shaft and slides up and down along the guide shaft, the support spring is sleeved on the guide shaft, one end of the support spring is abutted to the bottom of the guide sliding block, and the other end of the support spring is abutted to the lower platform.

10. The multi-directional motion translating, time varying stiffness base system of claim 9 wherein the third translational, stiffness varying mechanism comprises a stiffening cylinder, two linkage blocks rotationally coupled to the profile between the upper and lower platforms, and two push blocks symmetrically disposed along the guide blocks, two linear bearing sets, two leaf springs, two first links, two second links, two third links, and two fourth links; the linear bearing sets are fixed on the surface of the lower platform, the two pushing blocks horizontally slide along the two linear bearing sets, 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 the two sides of the guide sliding block respectively, one ends of the two first connecting rods are rotatably connected with the two sides of one translational sliding block respectively, the other ends of the two first connecting rods are rotatably connected with the two sides of one end of the guide sliding block respectively, one ends of the two second connecting rods are rotatably connected with the two sides of the other end of the guide sliding block respectively, one ends of the two third connecting rods are rotatably connected with one ends of the two pushing blocks respectively, one ends of the two fourth connecting rods are rotatably connected with the other ends of the two pushing blocks respectively, the other ends of the two fourth connecting rods are rotatably connected with the two ends of the other translational sliding block respectively, the output ends of the rigid adjusting cylinder are fixedly connected with one of the two pushing blocks respectively, the two bending rigidity adjusting cylinders are pushed by the rigid adjusting cylinders, and the bending rigidity of the leaf springs is changed.

11. The multi-directional motion converted time-varying stiffness base system of claim 7, wherein the number of the translational stiffness simulation platforms is not less than two, the platform bottom plate of each translational stiffness simulation platform is carried on the first guide rail group of the lower translational stiffness simulation platform, and the platform bottom plate of each translational stiffness simulation platform is connected with the sliding adjusting assembly of the lower translational stiffness simulation platform through the transmission shaft, so that the lower translational stiffness simulation platform controls the translational stiffness of the upper translational stiffness simulation platform in different motion directions.

12. The multi-directional motion converted time-varying stiffness base system according to claim 8, wherein the number of translational stiffness simulation platforms is not less than two, and the platform support plate of each translational stiffness simulation platform is fixedly connected with the top cone seat of the lower translational stiffness simulation platform, so that the lower translational stiffness simulation platform controls the translational stiffness of the upper translational stiffness simulation platform in different motion directions.

13. The multi-directional motion converted time-varying stiffness base system according to claim 10, wherein the number of the translational stiffness simulation platforms is not less than two, the lower platform of each translational stiffness simulation platform is carried on the translational guide rail group of the lower translational stiffness simulation platform, and the lower platform of each translational stiffness simulation platform is connected with the sliding component of the lower translational stiffness simulation platform through the transmission shaft, so that the lower translational stiffness simulation platform controls the translational stiffness of the upper translational stiffness simulation platform in different motion directions.