A multi-position locking, face-symmetric metamorphic multistable mechanism

Abstract

The present invention relates to a multi-posture locked, face-symmetrical metamorphic multistable mechanism, comprising: a base, a motion branch and a moving platform arranged vertically and radially stacked, wherein the base and the moving platform are connected via a motion branch; wherein the motion branch can be divided into three categories: a translation locking chain, a bending locking chain and a drive chain. wherein the translation locking chain is distributed on a vertical plane passing through the center of the mechanism, the bending locking chain and the drive chain are face-symmetrically distributed with the vertical plane as the vertical plane, and each moving rod on the chain is configured to rotate axially so that the base and the moving platform undergo relative motion, so that the base, the moving platform and the motion branch are at a singularity point, and so that the motion branch establishes a constraint. The mechanism provided by the present invention has the advantages of a large working space, easy control of the posture during motion, and autonomous locking and unlocking.

Description

[0001] The present application relates to the technical field of multi-stable mechanisms, specifically to a multi-stability mechanism with multi-position locking and plane-symmetric metamorphic multi-stable mechanism. Background Art

[0002] Multi-stable mechanisms are widely used in industrial robots, medical devices, aerospace and other fields. Their advantage is that they can switch between multiple stable states without requiring additional energy consumption to maintain a steady state, thus achieving the integration of multiple functions and adapting to different task requirements. Existing multi-stable mechanisms are mostly based on the energy storage properties of flexible materials such as buckling beams and springs to maintain a stable state. When the total energy of the mechanism is at a minimum, the mechanism reaches a steady state. Such a multi-stable mechanism needs to be composed of multiple overlapping bistable mechanisms, which increases the complexity of the mechanism. In addition, the flexible material will undergo asymmetric deformation during the process of the mechanism jumping to a stable state, which increases the uncertainty of the mechanism's movement. In addition, the flexibility of the flexible material also limits the working space of the mechanism to a certain extent.

[0003] To address the aforementioned issues, a mechanism using singular metamorphic cells for steady-state locking is proposed. Existing parallel mechanisms often use locking pins to limit the position of the movable joints during locking. These mechanisms, for example, employ compression springs, disposable locking pins with leaf springs, or reusable locking mechanisms using self-locking hinges. However, these mechanisms often rely on passive locking, requiring a certain force balance to unlock, lacking autonomous control capabilities. Summary of the Invention

[0004] The purpose of the present invention is to provide a plane-symmetrical metamorphic multistable mechanism with multi-posture locking to solve the problems of asymmetric buckling and high-order buckling occurring when switching stable states and passive locking when locking in the prior art multistable mechanisms.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A multi-position locking, plane-symmetrical metamorphic multistable mechanism comprises: a base vertically and radially stacked, six kinematic branch chains with three pairs of kinematic branches, and a moving platform, wherein the base and the moving platform are connected by three pairs of kinematic branches; wherein the three pairs of kinematic branches are:

[0007] The translation locking chain is composed of a rotating shaft hole and a moving rod connected in rotation with the axial direction at two different angles, and is rotationally connected to the base and the moving platform.

[0008] The curved locking chain is composed of two moving rods whose rotating shaft holes are perpendicular to each other and is rotatably connected to the base and the moving platform.

[0009] The drive chain is a telescopic structure composed of two moving rods, which is rotationally connected to the base and rigidly connected to the moving platform.

[0010] Among them, the translation locking chain is distributed on a vertical plane passing through the center of the mechanism, and each moving rod on the chain can rotate in the axial direction, so that the base and the moving platform approach or move away from each other, so that the base, the moving platform and the motion branch are at a singularity point, and the motion branch establishes a constraint; the drive chain is distributed with the vertical plane as a mirror symmetry, and the moving rods on the chain rotate or translate in the axial direction, so that the base and the moving platform approach or move away from each other; the bending locking chain is distributed on a vertical plane passing through the center of the mechanism, and each moving rod on the chain is configured to rotate in the axial direction or in the radial direction, so that the base and the moving platform deflect from each other, so that the base, the moving platform and the motion branch are at a singularity point, and the motion branch establishes a constraint.

[0011] As one preferred embodiment, the mechanism includes a drive assembly electrically connected to each of the moving rods to achieve target state driving of the moving rods in each of the moving branches in the axial and radial directions. The drive assembly includes at least first, second, third, fourth, fifth, and sixth drive mechanisms, and the target states include:

[0012] The first driving mechanism and the second driving mechanism are used to drive the moving rod in the driving chain to move to two stable states, a shortened state and a bent state, wherein the two stable states are respectively characterized by the base and the moving platform approaching and deflecting each other;

[0013] The third driving mechanism and the fourth driving mechanism are used to drive the moving rods in the translation locking chain to move to a first stable locking state, wherein the first stable locking state is characterized by causing the corresponding moving rods in the shortened singular state to establish a constraint;

[0014] The fifth driving mechanism and the sixth driving mechanism are used to drive the moving rods in the bending locking chain to move to a second stable locking state, wherein the second stable locking state is characterized by causing the corresponding moving rods in the bending singular state to establish constraints.

[0015] As one preferred embodiment, the translational locking chain is arranged on a surface perpendicular to the base, passing through the center of the base. The drive chain and the curved locking chain are symmetrically arranged about a surface perpendicular to the base, passing through the center of the base. The translational locking chain, the drive chain, and the curved locking chain are all hinged to the base via a rotating axis perpendicular to the base, passing through the center of the base. In the translational locking chain, the axis of the rotation hole of one moving rod is at a 90-degree angle to the component, while the axis of the rotation hole of the other moving rod is at a 135-degree angle to the component. The two components are hinged via a rotating axis. In the drive chain, the two moving rods form a coaxial telescopic structure. The moving rod at the lower axial end is hinged to the base via a rotating axis perpendicular to the base, passing through the center of the base. The moving rod at the upper axial end is rigidly connected to the moving platform and prevents relative movement. In the curved locking chain, the rotation axes of the two moving rods are perpendicular to each other, and the two components are hinged via a rotating axis. The moving rods located at the axial bottom end and the top end are hinged to the base and the moving platform through a rotating shaft, and the directions of the rotating shafts of the two are parallel.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] An embodiment of the present invention provides a multi-posture locked, face-symmetrical metamorphic multistable mechanism, comprising: a base vertically and radially stacked, six chains of three pairs of kinematic branches, and a moving platform, wherein the base and the moving platform are connected by three pairs of kinematic branches; wherein the three pairs of kinematic branches are: a translational locking chain, comprising kinematic rods rotatably connected at two different angles between a rotating shaft hole and the axial direction, and rotatably connected to the base and the moving platform; a drive chain, comprising a telescopic structure consisting of two kinematic rods, rotatably connected to the base and rigidly connected to the moving platform; and a bending locking chain, comprising two kinematic rods with mutually perpendicular rotating shaft holes, and rotatably connected to the base and the moving platform. Among them, the translation locking chain is distributed on the vertical plane passing through the center of the mechanism, and the moving rods on the chain are configured to rotate in the axial direction, so that the base and the moving platform approach or move away from each other, so that the base, the moving platform and the moving branch are at a singularity point, and the moving branch establishes a constraint; the bending locking chain is symmetrically distributed on both sides of the vertical plane passing through the center of the mechanism, and the moving rods on the chain are configured to rotate in the axial direction or in the radial direction, so that the base and the moving platform deflect each other, so that the base, the moving platform and the moving branch are at a singularity point, and the moving branch establishes a constraint; the drive chain is symmetrically distributed on both sides of the vertical plane passing through the center of the mechanism, and the moving rods on the chain translate in the axial direction or rotate in the radial direction, so that the base and the moving platform approach or move away from each other.

[0018] The technical solution provided by the present invention connects the base to the translational locking chain, drive chain, and bending locking chain through a revolving pair. The translational locking chain and bending locking chain are each composed of different moving rods connected by revolving pairs with different deflection angles. The drive chain is a telescopic structure composed of moving rods connected by moving pairs. When the telescopic structure of the drive chain moves axially, the mechanism is in an extended state and a shortened state. The position or posture of the moving rods in the translational locking chain is changed by the rotation of the moving rods, thereby achieving a singularity in the mechanism in the shortened state. In the singularity, the mechanism has special constraints and a unique geometric configuration, and the translational locking chain has local degrees of freedom. By further adjusting the position or posture of the moving rods, some of the moving rods are driven to move through the local degrees of freedom without relative motion between the base and the moving platform, changing the constraints of the translational locking chain on the moving platform. At this time, the mechanism achieves a cell change at the singular point, causing the mechanism to enter a translational locked state. When the telescopic structure of the drive chain moves axially and rotates radially, the mechanism is in a bent state; the position or posture of the moving rods in the translational locking chain and the bending locking chain are changed by rotating, thereby achieving a singularity in the mechanism in the bent state. In the singular state, the mechanism has special constraints and a characteristic geometric configuration, and the translational locking chain and the bending locking chain will have local degrees of freedom. By further adjusting the position or posture of the moving rods, some of the moving rods are driven to move through local degrees of freedom without relative motion between the base and the mobile platform, changing the constraints of the translational locking chain and the bending locking chain on the mobile platform. At this time, the mechanism achieves a cell change at the singular point, causing the mechanism to be in a bent locked state.

[0019] Thus, compared to existing multi-stable mechanisms, the embodiments of the present invention use rigid rods to form kinematic branches, each connected in parallel to the base, and employing singular metamorphic cells to switch between the shortened locking state and the bent locking state. The use of rigid rods avoids the problem of asymmetric buckling of flexible rods when subjected to force and also expands the mechanism's motion space. At the same time, when switching from the shortened state to the shortened locking state, and from the bent state to the bent locking state, active locking and unlocking can be achieved through the mechanism's own rods, resolving the problem of flexible mechanisms requiring external force to lock. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings required for the description of the present application. The drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0021] Figure 1 The overall structural diagram of the multi-posture locked plane-symmetric metamorphic multistable mechanism in the shortening process;

[0022] Figure 2 Schematic diagram of the overall structure of the multi-posture locked plane-symmetric metamorphic multistable mechanism in the bending process;

[0023] Figure 3 The overall structure diagram of the multi-posture locked plane-symmetric metamorphic multistable mechanism in the shortened state;

[0024] Figure 4 Schematic diagram of the overall structure of the plane-symmetrical metamorphic multistable mechanism with multi-posture locking in the shortened locked state;

[0025] Figure 5 Schematic diagram of the overall structure of the multi-posture locked plane-symmetric metamorphic multistable mechanism in the bending process;

[0026] Figure 6 Schematic diagram of the overall structure of the multi-posture locked plane-symmetric metamorphic multistable mechanism in the bent locked state;

[0027] Figure 7 Schematic diagram of the overall structure of a pair of translational locking chains of a plane-symmetric metamorphic multistable mechanism with multi-posture locking in a shortened locked state, with moving rods moving through local degrees of freedom;

[0028] Figure 8 Schematic diagram of the overall structure of the moving rods of a plane-symmetric metamorphic multistable mechanism with multi-posture locking, which is in a bent locking state and has one translation locking chain and one bending locking chain moving through local degrees of freedom. DETAILED DESCRIPTION

[0029] The present invention will be described in detail below with reference to the accompanying drawings and some embodiments. The figures provided in the following embodiments are merely schematic illustrations of the basic concept of the present invention. Therefore, the figures only show components relevant to the present invention and are not drawn according to the number, shape, and size of components in actual implementation. In actual implementation, the type, number, and proportion of each component may be varied arbitrarily, and the component layout may also be more complex.

[0030] In related technologies, multistable mechanisms typically require the overlapping of multiple bistable mechanisms, increasing their complexity. Furthermore, the flexible material undergoes asymmetrical deformation during the transition between stable states, adding uncertainty to the mechanism's motion. Furthermore, the flexibility of the flexible material also limits the mechanism's working space to a certain extent.

[0031] The present invention proposes a multi-posture locked plane-symmetrical metamorphic multistable mechanism, the main purpose of which is to solve the above-mentioned problems at the same time.

[0032] Please refer to Figures 1-6 As shown, Figure 1shows an exemplary mechanism in the process of shortening according to some embodiments of the present disclosure; Figure 2 shows an exemplary mechanism in a bending process according to some embodiments of the present disclosure; Figure 3 shows an exemplary mechanism in a compressed state according to some embodiments of the present disclosure; Figure 4 shows an exemplary mechanism in a compressed locked state according to some embodiments of the present disclosure; Figure 5 shows an exemplary mechanism in a bent state according to some embodiments of the present disclosure; Figure 6 An exemplary mechanism in a bent locked state is shown according to some embodiments of the present disclosure.

[0033] See also Figure 1 , an embodiment of the present invention provides a multi-posture locked plane-symmetrical metamorphic multistable mechanism, comprising: a base 100, a translation locking chain, a bending locking chain, a drive chain and a moving platform 500 arranged vertically and radially stacked, wherein the base 100 and the moving platform are connected by the translation locking chain, the drive chain and the bending locking chain; wherein the translation locking chain is composed of a moving rod 201, a moving rod 202, a moving rod 203, and a moving rod 204 connected by a rotation pair, and the moving rod 201 and the moving rod 204 are respectively connected to the base 100 and the moving platform 500 in rotation; the bending locking chain is composed of a moving rod 301, a moving rod 302, a moving rod 303, a moving rod 304 and a moving rod 305 in rotation; the drive chain is composed of a moving rod 401 and a moving rod 402 connected by a moving pair, and the moving rod 401 is connected to the base 100 in rotation, and the moving rod 402 is connected to the moving platform The platform 500 is rigidly connected; wherein the translation locking chain is distributed on a vertical plane passing through the center of the parallel mechanism, and each moving rod on the chain is configured to rotate in the axial direction, so that the base 100 and the moving platform 500 approach or move away from each other, so that the base 100, the moving platform 500 and the motion branch are at a singularity point, and the motion branch establishes a constraint; the bending locking chain is distributed on both sides of the vertical plane passing through the center of the mechanism, and each moving rod on the chain is configured to rotate in the axial direction or in the radial direction, so that the base and the moving platform deflect each other, so that the base, the moving platform and the motion branch are at a singularity point, and the motion branch establishes a constraint; the drive chain is distributed with the vertical plane as a mirror symmetry, and the moving rods on the chain translate in the axial direction or rotate in the radial direction, so that the base and the moving platform approach or move away from each other.

[0034] Specifically, vertical radial superposition is a mirror symmetrical arrangement perpendicular to the radial direction with the vertical plane passing through the center of the base 100 as the mirror, wherein the radial direction can be the direction indicated by a diameter of the vertical plane passing through the center of the base 100, or Figure 1 The left and right directions are indicated by arrows. Figures 1-8 As shown by the arrows in FIG, the base 100 and the movable platform 500 are arranged axially, with the base 100 positioned below the movable platform 500. The base is placed on the ground or on a frame of another mechanism; the movable platform 500 can be placed on a target object to adjust its motion posture. It can be understood that multistable mechanisms have a wide range of applications.

[0035] Specifically, the moving rod 210 and the base 100 in the translation locking chain are connected by a rotating pair, and the moving rod 201 can rotate in the radial direction relative to the base 100; the moving rod 202 and the moving rod 201 are connected by a rotating pair, wherein the rotating pair has the axial direction as the rotation axis direction; the moving rod 202 and the moving rod 203 are connected by a rotating pair, wherein the rotating pair has the direction perpendicular to the radial direction as the rotation axis direction; the moving rod 203 and the moving rod 204 are connected by a rotating pair, wherein the rotating pair has the axial direction as the rotation axis direction; the moving rod 204 is connected to the moving platform 500 through a rotating pair, wherein the rotating pair has the direction perpendicular to the radial direction as the rotation axis direction. The moving rod 301 in the bending locking chain is connected to the base 301 through a rotating pair, and the rotating pair has a rotation axis direction perpendicular to the radial direction and can rotate in the radial direction relative to the base 301; the moving rod 301 and the moving rod 302 are connected through a rotating pair, and the rotating pair has a rotation axis direction parallel to the radial direction; the moving rod 302 and the moving rod 303 are connected through a rotating pair, and the rotating pair has a rotation axis direction perpendicular to the radial direction; the moving rod 303 and the moving rod 304 are connected through a rotating pair, and the rotating pair has a rotation axis direction parallel to the radial direction; the moving rod 304 and the moving rod 305 are connected through a rotating pair, and the rotating pair has a rotation axis direction perpendicular to the radial direction; the moving rod 305 is connected to the moving platform 500 through a rotating pair, and the rotating pair has a rotation axis direction perpendicular to the radial direction. In the drive chain, the moving rod 401 is connected to the base 100 through a rotating pair, and the rotating pair has a rotation axis direction perpendicular to the radial direction, and the moving rod 401 can rotate in the radial direction relative to the base 100; the power rod 402 and the moving rod 401 are connected in a moving pair to form a telescopic structure, which can translate in the axial direction and rotate in the radial direction relative to the base 100; the moving rod 402 and the moving platform 500 are rigidly connected and no relative movement occurs.

[0036] The axial direction may be the direction in which the base 100 points toward the moving platform 500, such as Figure 1-8Direction indicated by arrow.

[0037] It's understood that the longer the moving rods in the translational locking chain, bending locking chain, and drive chain, the larger the mechanism's working space. The length and radius of each moving rod in the translational locking chain, bending locking chain, and drive chain, as well as the number of moving branches, can be determined based on the actual working space and load required by the mechanism.

[0038] As a specific explanation of this embodiment, with the cooperation of different rotating pairs, the mechanism can perform multiple stable state switching among the extended state, shortened state, bent state, shortened singular state, shortened locked state, bent singular state and bent shortened state.

[0039] When the telescopic structure composed of the moving rod 401 and the moving rod 402 in the drive chain moves to a certain position, that is, when the distance between the base 100 and the moving platform 500 is the longest, the mechanism is in an extended state;

[0040] When the telescopic structure composed of the moving rod 401 and the moving rod 402 in the drive chain moves to a certain position, that is, when the distance between the base 100 and the moving platform 500 is the shortest, the mechanism is in a shortened state;

[0041] During the process of the mechanism switching from the extended state to the shortened state, when the included angle between the moving rod 202 and the moving rod 203 in the two translation locking chains is 90°, that is, the rotational pair between the power moving rod 204 and the moving rod 203 and the rotational pair between the power moving rod 202 and the moving rod 201 are coaxial, it can be considered that the base 100, the platform 500 and the translation locking chain are at a singular point at this time. The singular point can indicate that the mechanism will experience a motion bifurcation phenomenon at this position, and the mechanism is in a shortened singular state at this time;

[0042] It will be appreciated that in this embodiment, the location of the singular point is determined based on parameters such as the angle between the revolving pairs of the moving rods in the two translation locking chains and the position coordinates of the base 100 and the moving platform 500. It will also be appreciated that the location of the singular point can be determined by modeling with the aid of computer-aided design tools.

[0043] The mechanism in the shortened singular state will have local degrees of freedom. Under the premise that the positions of the base 100, the moving platform 500, the moving rod 201 and the moving rod 204 remain unchanged, the moving rod 202 and the moving rod 203 of the two translation locking chains can be controlled to rotate around the rotational pair between the power rod 204 and the moving rod 203 and the rotational pair between the power rod 202 and the moving rod 201. The position and posture of the moving rods change, so that the constraints of the two translation locking chains on the entire mechanism change. New constraints are added on the basis of the original constraints. The moving platform 500 cannot move relative to the base 100, and the mechanism completes the singular transformation. At this time, the mechanism is in the shortened locked state.

[0044] When the moving rod 401 in the drive chain rotates radially to a certain position, the telescopic structure composed of the moving rod 401 and the moving rod 402 moves to a certain position, and the moving rods in the translation locking chain and the bending locking chain also move relative to each other, that is, when the moving platform 500 deflects relative to the base 100, the mechanism is in a bent state;

[0045] When the moving rod 401 in the drive chain rotates radially to a certain position, and the telescopic structure composed of the moving rods 401 and 402 moves to a certain position, the included angle between the moving rods 202 and 203 in one bending locking chain is 90°, and in the two bending locking chains, the rotational pair between the moving rods 301 and 302 and the rotational pair between the moving rods 305 and 304 are coaxial, the mechanism is in a bending singular state;

[0046] It will be appreciated that in this embodiment, the location of the singular point is determined based on parameters such as the angle between the revolving pair and the moving rod in the translational locking chain, the length of the moving rod in the bending locking chain, and the position coordinates of the base 100 and the moving platform 500. It should also be noted that computer-aided design tools can be used to build a model to determine the location of the singular point.

[0047] The mechanism in the bending singular state will have local degrees of freedom. Under the premise that the positions of the base 100, the moving platform 500, the moving rod 201, the moving rod 204, the moving rod 301 and the moving rod 305 remain unchanged, the moving rod 202 and the moving rod 203 of one translation locking chain can be controlled to rotate around the rotational pair between the power rod 204 and the moving rod 203 and the rotational pair between the power rod 202 and the moving rod 201, and the moving rod 302, the moving rod 303 and the moving rod 304 in the two bending locking chains can be controlled to rotate around the rotational pair between the moving rod 301 and the moving rod 302 and the rotational pair between the moving rod 304 and the moving rod 305. The position and posture of the moving rods change, which changes the constraints of one translation locking chain and two bending locking chains on the overall mechanism. New constraints are added on the basis of the original constraints. The moving platform 500 cannot move relative to the base 100, and the mechanism completes the singular transformation cell. At this time, the mechanism is in a bending locking state.

[0048] Among them, in the translation locking chain and the bending locking chain, the angle between each rotation pair and the rod in the moving rod can be adjusted to change the position of the singular point of the mechanism, which is used to change the posture of the mechanism in the shortened locking state and the bent locking state.

[0049] In a preferred embodiment, the translation locking chain is distributed on the vertical plane of the center of the mechanism, and the drive chain and the bending locking chain are symmetrically distributed on the vertical plane passing through the center of the mechanism. More preferably, the drive chain is distributed on the vertical plane of the center of the mechanism, and the translation locking chain and the bending locking chain are symmetrically distributed on the vertical plane passing through the center of the mechanism. By appropriately increasing the number of branches, the working space of the mechanism can be expanded to a certain extent, and the load-bearing capacity can be more uniform.

[0050] Similarly, the steady-state switching motion principle of the mechanism from the shortened locked state to the shortened state and from the bent locked state to the bent state is the same, but the rotation direction is opposite.

[0051] In this way, a multistable mechanism using singular metamorphic cells for locking can switch between different stable states by adjusting the motion and posture of the moving rod, thereby meeting different usage scenarios. Compared with flexible multistable mechanisms, this invention has a wider working space, easier posture control during movement, and can automatically lock and unlock in singular states, without the need for additional force to force locking, thus providing a wider range of application scenarios for multistable mechanisms.

[0052] See Figure 7 and Figure 8 , Figure 7 An exemplary motion bar moving through local degrees of freedom in a shortened, locked state is shown according to some embodiments of the present disclosure; Figure 8An exemplary kinematic rod moving through local degrees of freedom in a flexed locked state is shown according to some embodiments of the present disclosure.

[0053] In some embodiments, a drive assembly can be used to drive the moving rods to move at different angles of rotation. The drive assembly is electrically connected to each of the moving rods to achieve target state driving of the moving rods 401 and 402 in the drive chain, the moving rods 202 and 203 in the translation locking chain, and the moving rods 302 and 304 in the bending locking chain. The drive assembly includes at least: first, second, third, fourth, fifth, and sixth drive mechanisms. The target states include:

[0054] The first driving mechanism and the second driving mechanism are used to drive the moving rods 401 and 402 in the driving chain, so that the mechanism moves to two stable states, namely, a shortened state and a bent state, and the two stable states are respectively characterized by the base and the moving platform approaching and deflecting each other; the third driving mechanism and the fourth driving mechanism are used to drive the moving rods 202 and 203 in the translation locking chain, so that the mechanism moves to a first stable state locking, and the first stable state locking is characterized by prompting the corresponding moving rods in the shortened singular state to establish constraints; the fifth driving mechanism and the sixth driving mechanism are used to drive the moving rods 302, 303 and 304 in the bending locking chain to move to a second stable state locking, and the second stable state locking is characterized by prompting the corresponding moving rods in the bending singular state to establish constraints.

[0055] Specifically, the drive assembly is configured to provide driving force for each moving rod. The first drive mechanism and the second drive mechanism enable the moving rod 401 and the moving rod 402 to move and rotate, thereby realizing the shortening and bending of the mechanism; the third drive mechanism and the fourth drive mechanism enable the moving rod 202 and the moving rod 203 to rotate axially, thereby realizing the shortening locking state of the mechanism; the fifth drive mechanism and the sixth drive mechanism enable the moving rod 302, the moving rod 303 and the moving rod 304 to rotate in a direction perpendicular to the rod, thereby realizing the bending locking state of the mechanism.

[0056] Alternatively, the drive assembly can be a plurality of independent motors, with at least one motor allocated to each of the translation locking chain and the bending locking chain. The motors on the drive chain must simultaneously meet the two conditions of driving the moving rod 401 to rotate and the moving rod 402 to translate.

[0057] See again Figures 1-8In a preferred embodiment, the movement tendency of the moving rods 201, 202, 203 and the moving rod 204 of the two translational locking chains is to fold and unfold toward the inside of the mechanism, the distribution of the moving components 301, 302, 303, 304 and the moving rod 305 of the two bending locking chains is roughly Z-shaped, and the two drive chains are telescopic structures composed of the moving rod 401 and the moving rod 402.

[0058] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the various embodiments can be referenced to each other.

[0059] The complete workflow of the embodiment of the present invention is described below with reference to the accompanying drawings:

[0060] A multi-position locking, plane-symmetrical metamorphic multistable mechanism. When the mechanism is in the extended state, the second drive mechanism drives the moving rod 402 downward. Simultaneously with the downward movement of the dynamic platform 500, the individual moving rods in the bending and translational locking chains rotate accordingly. When the bottom of the moving rod 402 contacts the bottom of the moving rod 401, the mechanism stops moving, indicating that it is in the shortened state.

[0061] During the transition from the extended state to the shortened state, when the included angle between the moving rods 202 and 203 in the two translation locking chains is 90°, i.e., the rotational pair between the moving rods 204 and 203 and the rotational pair between the moving rods 202 and 201 are coaxial, the base 100, the platform 500, and the translation locking chains are at a singularity point. The third and fourth drive mechanisms drive the moving rods 202 and 203 on the two translation locking chains to rotate clockwise (as viewed from top to bottom) along the axial rotational pair, stopping after rotating 90°. The mechanism then completes the singularity transformation and enters the translation locking state.

[0062] When the mechanism is in the translation locking state, the third drive mechanism and the fourth drive mechanism drive the moving rod that has been sent to rotate counterclockwise along the axial rotation pair (looking from top to bottom), and stop after rotating 90°. At this time, the mechanism enters the shortening process and completes the unlocking.

[0063] When the first driving mechanism drives the moving rod 402 to move and the second driving mechanism drives the moving rod 401 to rotate, the moving platform 500 deflects relative to the base 100 and the mechanism enters a bent state.

[0064] During the mechanism's bending state, when the included angle between moving rod 202 and moving rod 203 in one bending locking chain is 90°, and in both bending locking chains, the rotational pair between moving rod 301 and moving rod 302 and the rotational pair between moving rod 305 and moving rod 304 are coaxial, the mechanism is in a bending singular state. At this point, the third drive mechanism drives moving rod 202 and moving rod 203 to rotate 90° clockwise (from top to bottom) about the rotational pair between moving rod 204 and moving rod 203 and the rotational pair between moving rod 202 and moving rod 201, and then stops. The fifth and sixth drive mechanisms drive moving rods 302, 303, and 304 in the two bending locking chains to rotate 90° clockwise (from left to right) about the rotational pair between moving rod 301 and moving rod 302 and the rotational pair between moving rod 304 and moving rod 305, and then stop. At this point, the mechanism realizes the singular metamorphosis and enters the bending locked state.

[0065] When the mechanism is in the bent locking state, the third driving mechanism drives the moving rod 202 and the moving rod 203 to rotate 90° counterclockwise (seen from top to bottom) around the rotation pair between the power moving rod 204 and the moving rod 203 and the rotation pair between the power moving rod 202 and the moving rod 201 and stop. The fifth driving mechanism and the sixth driving mechanism drive the moving rod 302, the moving rod 303 and the moving rod 304 in the two bent locking chains to rotate 90° counterclockwise (from left to right) around the rotation pair between the moving rod 301 and the moving rod 302 and the rotation pair between the moving rod 304 and the moving rod 305 and stop. The mechanism enters the bent state and is unlocked.

[0066] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative uses of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0067] It should also be noted that, in this document, the directions or positional relationships indicated by the terms "upper", "lower", "left", "right", "inside", "outside", etc. are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, relational terms such as "first", "second", "third", "fourth", "fifth" and "sixth" are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations, nor can they be understood as indicating or implying relative importance. Moreover, the term "include" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or terminal device that includes a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device.

[0068] The above is a detailed introduction to the multi-position locking, plane-symmetric metamorphic multistable mechanism provided by the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only intended to help understand the present application, and the contents of this specification should not be construed as limiting the present application. At the same time, for those skilled in the art, based on the present application, there will be various changes in the specific implementation methods and scope of application. It is not necessary and impossible to enumerate all implementation methods here, and the obvious changes or modifications derived therefrom are still within the scope of protection of the present application.

Claims

1. A multi-stability, plane-symmetrical metamorphic mechanism with multi-position locking, characterized in that: include: The base, motion branches, and moving platform are arranged vertically and radially stacked, and the base and the moving platform are connected by three pairs of motion branches; wherein the motion branches can be divided into three categories: a translation locking chain, which is composed of motion rods with rotational connections at two different angles between the rotating shaft hole and the axial direction, and is rotationally connected to the base and the moving platform; a bending locking chain, which is composed of two motion rods with rotational shaft holes perpendicular to each other, and is rotationally connected to the base and the moving platform; and a drive chain, which is a telescopic structure composed of two motion rods, and is rotationally connected to the base and rigidly connected to the moving platform. Among them, the translation locking chain is distributed on a vertical plane passing through the center of the mechanism, and each moving rod on the chain can rotate in the axial direction, so that the base and the moving platform approach or move away from each other, so that the base, the moving platform and the motion branch are at a singularity point, and the motion branch establishes a constraint; the drive chain is distributed with the vertical plane as a mirror symmetry, and the moving rods on the chain rotate or translate in the axial direction, so that the base and the moving platform approach or move away from each other; the bending locking chain is distributed on a vertical plane passing through the center of the mechanism, and each moving rod on the chain can rotate in the axial direction or radially, so that the base and the moving platform deflect each other, so that the base, the moving platform and the motion branch are at a singularity point, and the motion branch establishes a constraint.

2. A multi-stability, plane-symmetrical metamorphic mechanism with multi-position locking according to claim 1, characterized in that: The mechanism includes a drive assembly, which is electrically connected to each of the moving rods to achieve a target state driving of the rotation of each moving rod.

3. The multi-stability mechanism with plane symmetry and multi-position locking according to claim 2, characterized in that: The drive assembly includes at least a first drive mechanism, a second drive mechanism, a third drive mechanism, a fourth drive mechanism, a fifth drive mechanism, and a sixth drive mechanism, and the target state includes: The first driving mechanism and the second driving mechanism are used to drive the moving rod in the driving chain to move to two stable states, a shortened state and a bent state, wherein the two stable states are characterized by the base and the moving platform approaching and deflecting each other, respectively; The third driving mechanism and the fourth driving mechanism are used to drive the moving rods in the translation locking chain to move to a first stable locking state, wherein the first stable locking state is characterized by causing the corresponding moving rods in the shortened singular state to establish a constraint; The fifth driving mechanism and the sixth driving mechanism are used to drive the moving rods in the bending locking chain to move to a second stable locking state, wherein the second stable locking state is characterized by causing the corresponding moving rods in the bending singular state to establish constraints.

4. The multi-stability mechanism with plane symmetry and multi-position locking according to claim 1, characterized in that: The translation locking chain is arranged on a surface passing through the center of the base and perpendicular to the base.

5. The multi-stability mechanism with plane symmetry and multi-position locking according to claim 1, characterized in that: The driving chain and the bending locking chain are symmetrically arranged on a plane passing through the center of the base and perpendicular to the base.

6. The multi-stability mechanism with plane symmetry and multi-position locking according to claim 1, characterized in that: The translation locking chain, the driving chain and the bending locking chain are all hinged to the base through a rotating shaft perpendicular to the center of the base and perpendicular to the surface of the base.

7. The multi-stability mechanism with plane symmetry and multi-position locking according to claim 1, characterized in that: In the translation locking chain, the axis of the rotation hole of one moving rod is 90 degrees to the component, and the axis of the rotation hole of the other moving rod is 135 degrees to the component. The two components are hinged by a rotating shaft.

8. The multi-stability mechanism with plane symmetry and multi-position locking according to claim 1, characterized in that: In the drive chain, two moving rods form a coaxial telescopic structure; the moving rod located at the lower axial end is hinged to the base through a rotating shaft perpendicular to the center of the base and the surface of the base; the moving rod located at the top axial end is rigidly connected to the moving platform and does not move relative to each other.

9. The multi-stability mechanism with plane symmetry and multi-position locking according to claim 1, characterized in that: In the curved locking chain, the rotation axes of the two moving rods are perpendicular to each other, and the two components are hinged by a rotating shaft; the moving rods located at the axial bottom and top ends are hinged to the base and the moving platform by a rotating shaft, and the directions of the rotating shafts of the two are parallel.

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