Multi-attitude locked plane-symmetrical metamorphic multistable mechanism

Abstract

The invention relates to a multi-attitude locked plane-symmetrical metamorphic multistable mechanism which comprises a base, a motion branch chain and a movable platform which are vertically and radially overlapped, and the base is connected with the movable platform through the motion branch chain; wherein the motion branch chains can be divided into three types: translation locking chains, bending locking chains and driving chains. Wherein the translation locking chain is distributed on a vertical plane passing through the center of the mechanism, the bending locking chain and the driving chain are symmetrically distributed by taking the vertical plane as a plane, and each moving rod piece on the chains is configured to rotate along the axial direction, so that the base and the moving platform generate relative movement; the base, the movable platform and the motion branch chains are located at singular points, and the motion branch chains are restrained. The mechanism has the advantages that the working space is large, the posture in the movement process is easy to control, and automatic locking and unlocking can be achieved.

Description

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

[0002] Multi-stable mechanisms are widely used in industrial robots, medical devices, aerospace and other fields. Their advantages are that they can switch between multiple stable states, and no additional energy consumption is required to maintain the steady state, realizing the integration of multiple functions and adapting to different task requirements. Most of the existing multi-stable mechanisms are based on the energy storage characteristics of flexible materials such as buckled 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, and the flexible material will undergo asymmetric deformation during the process of the mechanism jumping to a steady state, increasing 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] In order to solve the above problems, a mechanism using singular cells for steady-state locking is proposed. When locking, existing parallel mechanisms mostly use locking pins to limit the movable joints, such as using compression springs, disposable locking pins with springs, and repeatable locking mechanisms using self-locking hinges. However, this type of mechanism is mostly passively locked, and when unlocking, it is also necessary to break a certain force balance to achieve unlocking, and lacks a certain degree of autonomous control ability. Summary of the invention

[0004] The purpose of the present invention is to provide a plane-symmetric 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 multistable mechanism in the prior art.

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

[0006] A multi-posture locked face-symmetric metamorphic multistable mechanism comprises: a base vertically and radially stacked, 6 chains of three pairs of motion branches and a moving platform, wherein the base and the moving platform are connected by three pairs of motion branches; wherein the three pairs of motion branches are respectively:

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

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

[0009] The driving 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 are close to or away from each other, so that the base, the moving platform and the motion branch chain are at a singularity point, and the motion branch chain establishes a constraint; the driving 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 are close to or 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 each other, so that the base, the moving platform and the motion branch chain are at a singularity point, and the motion branch chain establishes a constraint.

[0011] As one of the preferred solutions, the mechanism includes a drive assembly, which is electrically connected to each of the moving rods to achieve the target state drive of the rotation of the moving rods in each of the moving branches in the axial and radial directions. The drive assembly includes at least the 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 characterized by the base and the moving platform approaching and deflecting each other, respectively;

[0013] The third driving mechanism and the fourth driving mechanism are used to drive the moving rod in the translation locking chain to move to a first steady-state locking, wherein the first steady-state locking is characterized by causing the corresponding moving rod 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 of the preferred solutions, the translation locking chain is arranged on a surface passing through the center of the base and perpendicular to the base. The drive chain and the bending locking chain are arranged symmetrically on a surface passing through the center of the base and perpendicular to the base. The translation locking chain, the drive chain and the bending locking chain are all hinged to the base through a rotating shaft perpendicular to the surface passing through the center of the base and perpendicular to the base. In the translation locking chain, the axis of the rotation hole of one moving rod is 90° with the component, and the axis of the rotation hole of the other moving rod is 135° with the component, and the two components are hinged through a rotating shaft. In the drive chain, the two moving rods form a coaxial telescopic structure. The moving rod at the axial lower end is hinged to the base through a rotating shaft perpendicular to the surface passing through the center of the base and perpendicular to the base. The moving rod at the axial top end is rigidly connected to the moving platform and does not move relative to each other. In the bending locking chain, the rotation axes of the two moving rods are perpendicular to each other, and the two components are hinged through a rotating shaft. 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-symmetric metamorphic multistable mechanism, comprising: a base vertically and radially stacked, 6 chains with three pairs of motion branches and a moving platform, wherein the base and the moving platform are connected by three pairs of motion branches; wherein the three pairs of motion branches are: a translation locking chain, which is composed of motion rods whose rotational connections are made at two different angles between a rotating shaft hole and the axial direction, and is rotationally connected to the base and the moving platform. A drive chain, which is a telescopic structure composed of two types of motion rods, is rotationally connected to the base and rigidly connected to the moving platform. A bending locking chain, which is composed of two types of motion rods whose rotational shaft holes are perpendicular to each other, and is rotationally connected to the base and 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 is configured to rotate in the axial direction, so that the base and the moving platform are close to or away from each other, so that the base, the moving platform and the motion branch chain are at a singularity point, and the motion branch chain 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 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 are deflected from each other, so that the base, the moving platform and the motion branch chain are at a singularity point, and the motion branch chain establishes a constraint; the driving 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 are close to or away from each other.

[0018] Through the technical solution provided by the present invention, the base is connected with the translation locking chain, the driving chain and the bending locking chain through a rotating pair. The translation locking chain and the bending locking chain are respectively composed of different moving rods connected by rotating pairs with different deflection angles. The driving chain is a telescopic structure composed of moving rods connected by moving pairs. When the telescopic structure of the driving chain moves axially, the mechanism is in an extended state and a shortened state; the position or posture of the moving rod is changed by the rotation of the moving rod in the translation locking chain, so that the mechanism in the shortened state is singular. In the singular state, the mechanism has a geometric configuration with special constraints and characteristics, and the translation locking chain will have local degrees of freedom. By further adjusting the position or posture of the moving rod, some moving rods are driven to move through local degrees of freedom under the premise that the base and the mobile platform do not move relative to each other, and the constraints of the translation locking chain on the mobile platform are changed. At this time, the mechanism realizes the cell change at the singular point so that the mechanism is in a translation locking 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 rod is changed by rotating the moving rod in the translation locking chain and the bending locking chain, so that the mechanism in the bent state becomes singular. In the singular state, the mechanism has special constraints and characteristic geometric configurations, and the translation locking chain and the bending locking chain will have local degrees of freedom. By further adjusting the position or posture of the moving rod, some of the moving rods are driven to move through local degrees of freedom under the premise that the base and the mobile platform do not move relative to each other, and the constraints of the translation locking chain and the bending locking chain on the mobile platform are changed. At this time, the mechanism realizes the cell change at the singular point, making the mechanism in a bent locked state.

[0019] Thus, compared with the existing multi-stable mechanism, the embodiment of the present invention uses rigid rods to form a motion branch chain, each branch chain is connected in parallel to the base, and the shortened locking state and the bent locking state are switched in the form of a singular metamorphosis. The use of rigid rods avoids the problem of asymmetric buckling of the flexible rods when they are subjected to force, and also expands the motion space of the mechanism. 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 rods of the mechanism itself, solving the problem that the flexible mechanism requires external force to lock. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solution of the present application, the drawings required for use in the description of the present application will be briefly introduced below. 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 paying any creative labor.

[0021] Figure 1 It is a schematic diagram of the overall structure of the multi-posture locked plane-symmetric metamorphic multistable mechanism in the shortening process;

[0022] Figure 2 It is a schematic diagram of the overall structure of the multi-posture locked face-symmetric metamorphic multistable mechanism in the bending process;

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

[0024] Figure 4 It is a schematic diagram of the overall structure of the plane-symmetric metamorphic multistable mechanism with multi-posture locking in a shortened locking state;

[0025] Figure 5 It is a schematic diagram of the overall structure of the multi-posture locked face-symmetric metamorphic multistable mechanism in the bending process;

[0026] Figure 6 It is a schematic diagram of the overall structure of the face-symmetric metamorphic multistable mechanism with multi-posture locking in a bending locking state;

[0027] Figure 7 It is a schematic diagram of the overall structure of a pair of moving rods of a translation locking chain moving through local degrees of freedom in a plane-symmetric metamorphic multistable mechanism with multi-posture locking in a shortened locking state;

[0028] Figure 8 The schematic diagram of the overall structure of the moving rods of the plane-symmetric metamorphic multistable mechanism with multi-posture locking, which is in a bending 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 is described in detail below with reference to the accompanying drawings and some embodiments. The illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and the drawings only show components related to the present invention rather than the number, shape and size of components in actual implementation. The type, quantity and proportion of each component in actual implementation may be changed at will, and the component layout may also be more complicated.

[0030] In the related art, multi-stable mechanisms generally need to be composed of multiple overlapping bistable mechanisms, which increases the complexity of the mechanism, and the flexible material will undergo asymmetric deformation during the stable state jump process, which increases the uncertainty of the mechanism movement. In addition, the flexibility of the flexible material also limits the working space of the mechanism to a certain extent.

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

[0032] Please refer to Figure 1-Figure 6 As shown, Figure 1An exemplary mechanism in the process of shortening according to some embodiments of the present disclosure is shown; Figure 2 An exemplary mechanism in a bending process according to some embodiments of the present disclosure is shown; Figure 3 shows an exemplary mechanism in a compressed state according to some embodiments of the present disclosure; Figure 4 An exemplary mechanism in a compression locked state according to some embodiments of the present disclosure is shown; 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 The embodiment of the present invention provides a multi-posture locked plane-symmetric metamorphic multi-stable mechanism, comprising: a base 100, a translation locking chain, a bending locking chain, a driving 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 driving 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 connected by a rotation pair; the driving 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 base 100 and the moving platform 500 are 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 are close to or away from each other, so that the base 100, the moving platform 500 and the motion branch chain are at a singularity point, and the motion branch chain 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 are deflected to each other, so that the base, the moving platform and the motion branch chain are at a singularity point, and the motion branch chain 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 are close to or away from each other.

[0034] Specifically, the vertical radial stacking is arranged perpendicular to the radial direction and with the vertical plane passing through the center of the base 100 as a mirror symmetry, 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 can be Figure 1 The left and right directions are indicated by arrows. Figure 1-Figure 8 As shown by the arrow in , the base 100 and the moving platform 500 are arranged in the axial direction, wherein the base 100 is arranged below the moving platform 500. The base is arranged on the ground or on a rack of other mechanisms; the moving platform 500 can be arranged on the target object to complete the motion posture adjustment of the target object. It can be understood that the multi-stable mechanism has 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 by 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 relative to the base 301 in the radial direction; 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 from the base 100 to the moving platform 500, such as Figure 1-8Direction indicated by arrow.

[0037] It can be understood that the longer the moving rods in the translation locking chain, the bending locking chain and the driving chain are, the larger the working space of the mechanism is. The length and radius of each moving rod in the translation locking chain, the bending locking chain and the driving chain, as well as the number of each moving branch chain can be determined according to the actual working space and actual load required for the mechanism to move.

[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 formed by the moving rod 401 and the moving rod 402 in the driving 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 formed by the moving rod 401 and the moving rod 402 in the driving 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] In the process of switching the mechanism from the elongated 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 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 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, and the singular point can indicate that the mechanism will have a motion bifurcation phenomenon at this position, and the mechanism is in a shortened singular state at this time;

[0042] It can be understood that in this embodiment, the position of the singular point is obtained according to the angle between the rotating pair of the moving rod and the moving rod in the two translation locking chains and the position coordinates of the base 100 and the moving platform 500. It can also be explained that the model can be established with the help of computer-aided design tools to determine the position of the singular point.

[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 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. The position and posture of the moving rod change, so that the constraint conditions of the two translation locking chains on the overall 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 driving chain rotates to a certain position in the radial direction, 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, the moving platform 500 deflects relative to the base 100, and the mechanism is in a bending state;

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

[0046] It can be understood that in this embodiment, the position of the singular point is obtained according to the angle between the rotating pair of the moving rod and the moving rod in the translation 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 can also be explained that the model can be established with the help of computer-aided design tools to determine the position 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 rotation pair between the power-exerting rod 204 and the moving rod 203 and the rotation pair between the power-exerting 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 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. The position and posture of the moving rod 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 locked 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 translational 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 translational 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 branch chains, 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 multi-stable mechanism using a singular cell for locking can switch between different stable states by adjusting the movement and posture of the moving rod, thereby meeting different usage scenarios. Compared with a flexible multi-stable mechanism, the present invention has a wider working space, and the posture during movement is easier to control. It can be locked and unlocked autonomously in a singular state, and does not require additional force for forced locking, which provides a wider range of application scenarios for the multi-stable mechanism.

[0052] See also Figure 7 and Figure 8 , Figure 7 An exemplary motion bar moving through local degrees of freedom in a shortened locked state according to some embodiments of the present disclosure is shown; 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, the driving assembly can be used to drive the moving rods to move at different angles of rotation. The driving assembly is electrically connected to each of the moving rods to achieve target state driving of the moving rods 401 and 402 in the driving 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 driving assembly includes at least: first, second, third, fourth, fifth and sixth driving mechanisms, and the target states include:

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

[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 rods, thereby realizing the bending locking state of the mechanism.

[0056] Alternatively, the drive assembly may be a plurality of independent motors, with at least one motor allocated to each of the translation locking chain and the bending locking chain, and 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 Figure 1-Figure 8In a preferred embodiment, the movement trend 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 driving chains are telescopic structures composed of moving rods 401 and moving rods 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 or 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-stability mechanism with plane symmetry and multi-position locking. When the mechanism is in the extended state, the second driving mechanism drives the moving rod 402 to move downward. When the moving platform 500 moves downward, each moving rod in the bending locking chain and the translation locking chain will also rotate accordingly. When the bottom of the moving rod 402 contacts the bottom of the moving rod 401, the mechanism stops moving, and the mechanism is in the shortened state.

[0061] In the process of switching the mechanism 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 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 are coaxial, the base 100, the platform 500 and the translation locking chain are at a singular point, and the third driving mechanism and the fourth driving mechanism drive the moving rod 202 and the moving rod 203 on the two translation locking chains to rotate clockwise along the axial rotation pair (from top to bottom), and stop after rotating 90°. At this time, the mechanism completes the singular 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 bending state.

[0064] When the mechanism enters the bending state, the included angle between the moving rod 202 and the moving rod 203 in one bending locking chain is 90° and in the two bending locking chains, the rotational pair between the moving rod 301 and the moving rod 302 and the rotational pair between the moving rod 305 and the moving rod 304 are coaxial, and the mechanism is in the bending singular state. At this time, the third driving mechanism drives the moving rod 202 and the moving rod 203 to rotate 90° clockwise (from top to bottom) around 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 and stop, and 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 bending locking chains to rotate 90° clockwise (from left to right) 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 and stop. At this point, the mechanism achieves a singular metamorphosis and enters a 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 (viewed 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] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0067] It should also be noted that, in this article, the orientation or position relationship indicated by the terms "upper", "lower", "left", "right", "inside", "outside", etc. is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, relational terms such as "first", "second", "third", "fourth", "fifth" and "sixth" are only 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 including a series of elements includes not only those elements, but also 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 a multi-posture locked face-symmetric metamorphic multistable mechanism provided by the present application. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the present application, and the content of this specification should not be understood as a limitation on the present application. At the same time, for those of ordinary skill in the art, according to the present application, there will be different forms of changes in the specific implementation methods and application scopes. It is not necessary and impossible to list all the 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-position locking plane-symmetric metamorphic multistable mechanism, 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 a motion rod with a rotational connection whose rotational axis hole and the axial direction are at two different angles, and is rotationally connected to the base and the moving platform. A bending locking chain, which is composed of two motion rods with rotational axis holes perpendicular to each other, and is rotationally connected to the base and the moving platform. A driving chain, which is a telescopic structure composed of two motion rods, 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 are close to or away from each other, so that the base, the moving platform and the motion branch chain are at a singularity point, and the motion branch chain establishes a constraint; the driving 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 are close to or 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 chain are at a singularity point, and the motion branch chain establishes a constraint.

2. The multi-position locking plane-symmetric metamorphic multistable mechanism according to claim 1, characterized in that: The mechanism includes a driving assembly, and the driving assembly is electrically connected to each of the moving rods to achieve a target state driving for rotating each of the moving rods.

3. The multi-position locking plane-symmetric metamorphic multistable mechanism according to claim 2, characterized in that: The drive assembly at least includes 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 rod in the translation locking chain to move to a first steady-state locking, wherein the first steady-state locking is characterized by causing the corresponding moving rod 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-position locking plane-symmetric metamorphic multistable mechanism 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-position locking plane-symmetric metamorphic multistable mechanism according to claim 1, characterized in that: The driving chain and the bending locking chain are symmetrically arranged on a surface passing through the center of the base and perpendicular to the base.

6. The multi-position locking plane-symmetric metamorphic multistable mechanism 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-position locking plane-symmetric metamorphic multistable mechanism 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 another moving rod is 135 degrees to the component, and the two components are hinged by a rotating shaft.

8. The multi-position locking plane-symmetric metamorphic multistable mechanism according to claim 1, characterized in that: In the drive chain, two types of moving rods form a coaxial telescopic structure. The moving rod at the axial lower 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 at the axial top end is rigidly connected to the moving platform and does not move relative to it.

9. The multi-position locking plane-symmetric metamorphic multistable mechanism according to claim 1, characterized in that: In the bending 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 at the axial bottom and top are hinged with the base and the moving platform by a rotating shaft, and the directions of the two rotating shafts are parallel.

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