阅读说明：本技术 一种基于形状记忆合金的分级递进式旋转驱动装置及其控制方法 (Hierarchical progressive rotation driving device based on shape memory alloy and control method thereof ) 是由 沈传亮 徐孝东 高镇海 石博文 郑成锋 于 2019-10-28 设计创作，主要内容包括：本发明公开了一种基于形状记忆合金的分级递进式旋转驱动装置,包括：旋转壳内轴；以及旋转壳,其可转动的套设在所述旋转壳内轴外侧,在所述旋转壳上具有第一通孔和第二通孔；两个形状记忆合金丝,其分别缠绕在所述旋转壳上,所述两个形状记忆合金丝的一端通过第一通孔和第二通孔与所述旋转壳内轴固定连接；多个节点线,其一端分别连接在特定级数的形状记忆合金丝上；中央控制器,其一端与所述多个节点线的另一端相连接,另一端与所述连接节点相连接。本发明还公开了一种基于形状记忆合金的分级递进式旋转驱动装置的控制方法,能够通过不同的驱动角度实现分级递进式控制。(The invention discloses a hierarchical progressive rotary driving device based on shape memory alloy, which comprises: rotating the inner shaft of the shell; the rotating shell is rotatably sleeved on the outer side of the inner shaft of the rotating shell, and a first through hole and a second through hole are formed in the rotating shell; the two shape memory alloy wires are respectively wound on the rotating shell, and one ends of the two shape memory alloy wires are fixedly connected with the inner shaft of the rotating shell through a first through hole and a second through hole; one end of each node line is connected to the shape memory alloy wires in a specific stage number respectively; and one end of the central controller is connected with the other ends of the node lines, and the other end of the central controller is connected with the connecting node. The invention also discloses a control method of the grading progressive rotary driving device based on the shape memory alloy, which can realize grading progressive control through different driving angles.)

1. A stepped progressive rotary drive device based on shape memory alloy, comprising:

rotating the inner shaft of the shell; and

the rotary shell is of a hollow cylindrical structure with openings at two ends, the rotary shell is rotatably sleeved on the outer side of the inner shaft of the rotary shell, and a first through hole and a second through hole are formed in the rotary shell;

the shape memory alloy wire is wound on the lower part of the rotating shell, and one end of the shape memory alloy wire penetrates through the first through hole and is fixedly connected with the inner shaft of the rotating shell;

the superelastic shape memory alloy wire is wound on the upper part of the rotating shell, and one end of the superelastic shape memory alloy wire penetrates through the second through hole and is fixedly connected with the inner shaft of the rotating shell;

wherein the other end of the shape memory alloy wire is connected with the other end of the superelastic shape memory alloy wire to form a connection node which is fixed on the rotating shell;

one end of each node line is connected to the shape memory alloy wire according to the number of winding turns of the shape memory alloy;

a central controller, one end of which is simultaneously connected with the other ends of the plurality of node lines, and the other end of which is connected with the connection node;

an auxiliary power supply connected with the central controller to form a closed circuit;

wherein the central controller is capable of controlling any one of the node lines to be connected into the closed circuit.

2. The progressive shape memory alloy-based rotary drive device of claim 1, further comprising:

a resistor disposed between the central controller and the connection node.

3. A stepped, progressive, rotary drive device based on shape memory alloy as claimed in claim 2 wherein the maximum elongation of said shape memory alloy wire and said superelastic shape memory alloy wire is between 5% and 10%.

4. The stepped, progressive, rotary drive device based on shape memory alloy of claim 3, wherein the handedness of the shape memory alloy wire and the superelastic shape memory alloy wire on the rotating shell is the same and both the shape memory alloy wire and the superelastic shape memory alloy wire are wound with a monofilament.

5. The stepped, progressive, rotary drive device based on shape memory alloy as claimed in claim 1 wherein the superelastic shape memory alloy wire is initially in a pre-tensioned state and the shape memory alloy wire is initially in a tensioned state.

6. A control method of a stepped progressive rotary drive based on a shape memory alloy using the stepped progressive rotary drive based on a shape memory alloy according to any one of claims 1 to 5, characterized by comprising the processes of:

after receiving the control signal, the central controller selectively connects the corresponding node line into the closed circuit, and energizes the shape memory alloy wire connected into the closed circuit to heat and contract the shape memory alloy wire and drive the rotating shell to rotate to a driving angle relative to the inner shaft of the rotating shell, wherein the superelasticity shape memory alloy wire is stressed and stretched in the process to realize the driving effect;

after the central controller is disconnected from the nodal line, the superelastic shape-memory alloy wire causes the rotating shell to rotate reversely relative to the inner shaft of the rotating shell by restoring force, and simultaneously stretches the shape-memory alloy wire to return the rotating shell to the initial position.

7. The control method of a stepped progressive rotary drive apparatus based on a shape memory alloy according to claim 6, characterized in that the drive angle satisfies:

in the formula, theta is a driving angle, n is the number of node line stages connected into a circuit, l is the original length of the single-stage shape memory alloy wire, t is the elongation of the shape memory alloy wire, R is the radius of an inner shaft of the rotating shell, and d is the diameter of the bearing.

Technical Field

The invention relates to the technical field of driving devices, in particular to a graded progressive rotary driving device based on a shape memory alloy and a control method thereof.

Background

With the progress of science and technology, more and more intelligent technologies are widely applied in life, and the intelligent technologies also comprise intelligent materials, so that the traditional structure is simplified by the intelligent materials, and convenience is brought to production and processing.

The traditional rotary driver mainly adopts electromagnetic driving and mainly comprises a sensor, a driver, a controller and the like, and has the defects of complex and heavy structure, high impact noise, low energy density and the like.

Chinese patent document CN208880718U provides a rotary driving device for a robot, the robot includes a robot main body and a rotating component, wherein the rotary driving device includes a mounting base plate, a driving wheel, a driving motor, a driven wheel, a transmission belt, a rotating shaft, a sleeve-shaped bearing seat and a bearing. The mounting base plate is fixedly connected with the robot main body, the driving motor enables the driving wheel to rotate, and the driving motor is fixed on the mounting base plate; the transmission belt is wound between the driving wheel and the driven wheel; the rotating shaft is provided with a rotating part, a connecting part and an installation part, the connecting part is used for being fixedly connected with the rotating part, the installation part is connected between the rotating part and the connecting part, and the driven wheel is sleeved on the installation part in a mode of not rotating relative to the installation part; the bearing frame cover is established in the outside of rotating part and is fixed with mounting substrate. Compared with the prior art, the rotary driving device provided by the invention has the advantages of stable structure, reliable transmission, low cost, smaller overall volume and capability of saving space.

However, the existing rotary driving device has too complicated structure, difficult manufacturing and processing and too complicated operation, and the application occasions of the driver are greatly reduced due to the larger volume.

The advent of smart materials provides a new idea for solving the above-mentioned problems. The memory alloy is used as a typical intelligent material, has the characteristics of superelasticity, shape memory, corrosion resistance, fatigue resistance and the like, realizes the stretching from low-temperature stretching to high-temperature contraction by utilizing the transformation of martensite phase to austenite phase in the process from low temperature to high temperature of the shape memory alloy, forms displacement difference and restoring force, is used as a driving element of a rotary driving device, and can realize the real-time stretching and folding of a driven piece by combining a mechanical structure and an electric control unit.

Disclosure of Invention

The invention aims to design and develop a graded progressive rotary driving device based on shape memory alloy, which is characterized in that a central controller is used for electrifying a shape memory alloy wire, the generated restoring force drives a rotary shell to generate a driving angle relative to an inner shaft of the rotary shell, and after the shape memory alloy wire is powered off, the restoring force of a super-elastic shape memory alloy wire drives the rotary shell to return to an initial position.

The invention also aims to design and develop a control method of the grading progressive rotary driving device based on the shape memory alloy, which can generate different driving angles by electrifying and heating the shape memory alloy wires with different grades, thereby realizing the grading progressive control of the device.

The technical scheme provided by the invention is as follows:

a stepped progressive rotary drive device based on shape memory alloy, comprising:

rotating the inner shaft of the shell; and

the rotary shell is of a hollow cylindrical structure with openings at two ends, the rotary shell is rotatably sleeved on the outer side of the inner shaft of the rotary shell, and a first through hole and a second through hole are formed in the rotary shell;

the shape memory alloy wire is wound on the lower part of the rotating shell, and one end of the shape memory alloy wire penetrates through the first through hole and is fixedly connected with the inner shaft of the rotating shell;

the superelastic shape memory alloy wire is wound on the upper part of the rotating shell, and one end of the superelastic shape memory alloy wire penetrates through the second through hole and is fixedly connected with the inner shaft of the rotating shell;

wherein the other end of the shape memory alloy wire is connected with the other end of the superelastic shape memory alloy wire to form a connection node which is fixed on the rotating shell;

one end of each node line is connected to the shape memory alloy wire according to the number of winding turns of the shape memory alloy;

a central controller, one end of which is simultaneously connected with the other ends of the plurality of node lines, and the other end of which is connected with the connection node;

an auxiliary power supply connected with the central controller to form a closed circuit;

wherein the central controller is capable of controlling any one of the node lines to be connected into the closed circuit.

Preferably, the method further comprises the following steps:

a resistor disposed between the central controller and the connection node.

Preferably, the maximum elongation of the shape memory alloy wire and the superelastic shape memory alloy wire is 5% -10%.

Preferably, the rotation directions of the shape memory alloy wire and the superelastic shape memory alloy wire on the rotating shell are the same, and the shape memory alloy wire and the superelastic shape memory alloy wire are wound by using monofilaments.

Preferably, the superelastic shape memory alloy wire is initially in a pre-tensioned state and the shape memory alloy wire is initially in a stretched state.

A control method of a stepped progressive rotary driving device based on a shape memory alloy uses the stepped progressive rotary driving device based on the shape memory alloy, and comprises the following processes:

after receiving the control signal, the central controller selectively connects the corresponding node line into the closed circuit, and energizes the shape memory alloy wire connected into the closed circuit to heat and contract the shape memory alloy wire and drive the rotating shell to rotate to a driving angle relative to the inner shaft of the rotating shell, wherein the superelasticity shape memory alloy wire is stressed and stretched in the process to realize the driving effect;

after the central controller is disconnected from the nodal line, the superelastic shape-memory alloy wire causes the rotating shell to rotate reversely relative to the inner shaft of the rotating shell by restoring force, and simultaneously stretches the shape-memory alloy wire to return the rotating shell to the initial position.

Preferably, the driving angle satisfies:

in the formula, theta is a driving angle, n is the number of node line stages connected into a circuit, l is the original length of the single-stage shape memory alloy wire, t is the elongation of the shape memory alloy wire, R is the radius of an inner shaft of the rotating shell, and d is the diameter of the bearing.

The invention has the following beneficial effects:

(1) according to the grading progressive type rotary driving device based on the shape memory alloy, the rotary shell is driven relative to the inner shaft of the rotary shell through the restoring force of the shape memory alloy wire, and the rotary shell is reset through the restoring force of the super-elastic shape memory alloy.

(2) The control method of the grading progressive rotary driving device based on the shape memory alloy can generate different driving angles by electrifying and heating the shape memory alloy wires in different grades, thereby realizing grading control of the device, and being simple, reliable and sensitive in control.

Drawings

Fig. 1 is a schematic structural diagram of a stepped progressive rotation driving device based on a shape memory alloy according to the present invention.

Fig. 2 is a schematic diagram of the starting operation process of the control method of the stepped progressive rotary driving device based on the shape memory alloy.

Detailed Description

The present invention is described in further detail below in order to enable those skilled in the art to practice the invention with reference to the description.

The invention provides a graded progressive rotary driving device based on shape memory alloy, which is characterized in that a shape memory alloy wire is electrified and heated to generate restoring force to drive a rotary shell to generate a driving angle relative to an inner shaft of the rotary shell, and after the shape memory alloy wire is powered off, the restoring force of a super-elastic shape memory alloy wire drives the rotary shell to return, so that the driving device is realized.

As shown in fig. 1, the overall structure of the stepped progressive rotary driving device based on shape memory alloy according to the present invention is schematically illustrated, and the stepped progressive rotary driving device includes: the rotation case inner shaft 110, the rotation case 120, the plurality of bearings 121, the first through hole 122, the second through hole 123, the shape memory alloy wire 130, the superelastic shape memory alloy wire 140, the connection node 141, the plurality of node lines, the central controller 150, the auxiliary power source 160, and the protection resistor 170, and in the present embodiment, the plurality of node lines include a first-stage node line 181, a second-stage node line 182, a third-stage node line 183, a fourth-stage node line 184, and a fifth-stage node line 185.

The rotating shell inner shaft 110 is a fixed part, the rotating shell 120 is a hollow cylindrical structure with openings at two ends, the rotating shell 120 is rotatably sleeved outside the rotating shell inner shaft 110 through a plurality of bearings 121, and a first through hole 122 and a second through hole 123 are formed in the side wall of the rotating shell 120; a shape memory alloy wire 130 is wound on the lower part of the outer side wall of the rotating shell 120, and one end of the shape memory alloy wire 130 is fixedly connected with the rotating shell inner shaft 110 through a first through hole 122; a superelastic shape memory alloy wire 140 is wound around the upper outer portion of the sidewall of the rotating shell 120, and one end of the superelastic shape memory alloy wire 140 is fixedly connected to the rotating shell inner shaft 110 through a second through hole 123; wherein the other end of the shape memory alloy wire 130 and the other end of the superelastic shape memory alloy wire 140 are connected to form a connection node 141, and the connection node 141 is fixed to the rotating case 120; one end of each node line is connected to the shape memory alloy wires 130 with different turns, wherein the shape memory alloy wires 130 with different turns are the shape memory alloy wires 130 which are spaced from the connecting nodes 141 every other turn; a plurality of nodes respectively disposed on the shape memory alloy wire 130 every other turn from the connection node 141, and one ends of the plurality of node lines are respectively connected to the plurality of nodes in a one-to-one correspondence, and the plurality of node lines are respectively connected to the shape memory alloy wire 130 through the plurality of nodes; a central controller 150 having one end connected to the other ends of the plurality of node lines and the other end connected to the connection node 141; an auxiliary power supply 160 is connected to the central controller 150 to form a closed circuit, wherein the central controller 150 has an auxiliary power supply switch capable of controlling any one of the node lines to be connected to the closed circuit; and a protection resistor 170 arranged in the closed circuit for preventing the closed circuit from being overloaded due to overlarge current of the closed circuit.

In this embodiment, a first node 191 is provided on the shape memory alloy wire 130 spaced apart from the connection node 141 by one turn, a first stage node line 181 has one end connected to the first node 191 and the other end connected to an auxiliary power switch in the central controller 150, a second node 192 is provided on the shape memory alloy wire 130 spaced apart from the first node 191 by one turn, a second stage node line 182 has one end connected to the second node 192 and the other end connected to the auxiliary power switch in the central controller 150, a third node 193 is provided on the shape memory alloy wire 130 spaced apart from the second node 192 by one turn, a third stage node line 183 has one end connected to the third node 193 and the other end connected to the auxiliary power switch in the central controller 150, a fourth node 194 is provided on the shape memory alloy wire 130 spaced apart from the third node 193 by one turn, and a fourth stage node line 184 has one end connected to the fourth node 194, the other end is connected with an auxiliary power switch in the central controller 150, a fifth node 195 is arranged on the shape memory alloy wire 130 which is separated from the fourth node 194 by a circle, one end of a fifth node line 185 is connected with the fifth node 195, and the other end is connected with the auxiliary power switch in the central controller 150.

In the device, the superelastic shape memory alloy wire 140 is in a pre-tightening state at the beginning, the shape memory alloy wire 130 is in a stretching state at the beginning, the maximum stretching rates of the shape memory alloy wire 130 and the superelastic shape memory alloy wire 140 are between 5% and 10%, the rotating directions of the shape memory alloy wire 130 and the superelastic shape memory alloy wire 140 on the rotating shell 120 are the same, and the shape memory alloy wire 130 and the superelastic shape memory alloy wire 140 are wound by adopting monofilaments, so that the aim of better heat dissipation is fulfilled; in the present embodiment, the shape memory alloy wire 130 is made of Ni-Ti alloy, and preferably, the shape memory alloy wire 130 is made of Au-Cd alloy, Cu-Zn-A1 alloy, Cu-Zn-Sn alloy or Ni-Ti-Pd alloy.

The stepped progressive rotary driving device based on the shape memory alloy realizes the driving of the rotary shell relative to the inner shaft of the rotary shell through the restoring force of the shape memory alloy wire and realizes the returning of the rotary shell through the restoring force of the superelastic shape memory alloy.

The invention also provides a control method of the grading progressive rotary driving device based on the shape memory alloy, which comprises the following processes:

after the central controller receives the control signal, the auxiliary power switch selectively connects the corresponding node line to the closed circuit, and energizes the shape memory alloy wire connected to the closed circuit, so that the shape memory alloy wire is heated and contracted, and the rotating shell is driven to rotate to a driving angle relative to the inner shaft of the rotating shell, and in the process, the superelasticity shape memory alloy wire is stressed and stretched to realize a driving effect, as shown in fig. 2.

After the central controller is disconnected from the nodal line, the superelastic shape-memory alloy wire causes the rotating shell to rotate reversely relative to the inner shaft of the rotating shell by restoring force, and simultaneously stretches the shape-memory alloy wire to return the rotating shell to the initial position.

The driving angle satisfies:

in the formula, theta is a driving angle, n is the number of node line stages connected into a circuit, l is the original length of the single-stage shape memory alloy wire, t is the elongation of the shape memory alloy wire, R is the radius of an inner shaft of the rotating shell, and d is the diameter of the bearing.

The control method of the grading progressive rotary driving device based on the shape memory alloy can generate different driving angles by electrifying and heating the shape memory alloy wires in different grades, thereby realizing grading control of the device, and being simple, reliable and sensitive in control.

While embodiments of the invention have been described above, it is not limited to the applications set forth in the description and the embodiments, which are fully applicable to various fields of endeavor for which the invention may be embodied with additional modifications as would be readily apparent to those skilled in the art, and the invention is therefore not limited to the details given herein and to the embodiments shown and described without departing from the generic concept as defined by the claims and their equivalents.