CN110788845A - An electronically controlled shape memory alloy wire-driven snake robot - Google Patents

Abstract

The patent of the present invention discloses an electronically controlled memory alloy wire snake-shaped robot, which is mainly composed of a universal joint, a memory alloy wire and an electric control device. The snake-shaped robot is connected by a plurality of snake-body joints, and each snake-body joint is composed of four universal joints, four memory alloy wires, and an electric control device. The four memory alloy wires fixed around the joints of the snake body are controlled to contract or relax through the electronic control device, so that the joints of the snake body are turned in a certain direction. A plurality of snake body joints are connected together, and under the corresponding setting of the electronic control device, each snake body joint rotates in the corresponding direction to drive the robot to complete the corresponding movement. The memory alloy wire drive can realize the miniaturization of the robot, and at the same time ensure that the robot can make complex movements, so that it has the ability to move in complex environments. The snake-like robot has great advantages in exploration and other aspects. The invention patent has advanced guiding significance and practical value for the research and application of shape memory alloy wire.

Description

An electronically controlled shape memory alloy wire-driven snake robot

technical field

The patent of the present invention relates to the field of shape memory alloy robots, in particular to an electronically controlled shape memory alloy wire-driven snake-shaped robot.

Background technique

In this field, there are several ways to drive snake robots. The winding-type line-following snake robot adopts an arc-shaped walking module, the structure is more complex, and the overall machine is heavier, which cannot realize the exploration of small terrain. The bevel gear motor turns to the serpentine robot, which requires multiple motors, which is cumbersome and complicated to control the robot. The spherical hinge snake robot has a simple joint structure and affects its own rotation. The steering gear turns to the robot, with multiple steering gears, limited climbing ability and weak movement performance. The wire-pulling snake robot has a complex overall design and weak mechanical strength. The bristles drive the snake-like robot, which is slow and inflexible. There are many different types of robots, too many to list here.

In this context, combining the shortcomings and advantages of the above-mentioned various robots, the patent of the present invention adopts a new type of material - shape memory alloy wire to drive the snake-shaped robot. Shape memory alloys have a certain shape memory function and are composed of two main metal raw materials. In order to change the macroscopic size of the shape memory alloy wire, it is necessary to apply a certain voltage to its two ends to increase its temperature, thereby causing the shape change. When it needs to be restored to the original length, the voltage across the memory alloy wire needs to be reduced to restore the temperature to the original temperature. In addition, the shape change of the snake robot when turning is proportional to the shrinkage of the memory alloy wire, and the time required to restore the original shape is also proportional to the shrinkage of the memory alloy wire.

The motion principle of the snake-shaped robot is to use the tension generated by the deformation of the memory alloy wire to make the universal joint rotate. The rotation angles of multiple universal joints are superimposed, so that one joint of the robot can move in multiple directions, and the direction of each joint is turned to move. , which constitutes the forward or turning motion of the snake-like robot. The snake body of the snake robot is connected by a plurality of universal joints. Each snake body joint is composed of four universal joints. Except for the universal joints at the joint head and the joint tail, the same structure is carried out. Modified so that it can be connected with memory alloy wire. Drop glue between the universal joints for adhesion. The memory alloy wire is connected to the electronic control device connected to the tail of each joint to ensure the voltage required for its deformation. The universal joint and the memory alloy wire together complete the rotation of a joint, and the rotation of each joint together constitutes the complex motion of the snake robot.

In summary, the snake robot driven by memory alloy wire has the following advantages compared with the traditional snake robot: the structure is simple, the snake body is light, and it can be miniaturized, and it can realize the task of surveying small terrain. It has strong sports performance, high mechanical strength and flexible movement. The application of memory alloy wire to the field of snake robot has advanced guiding significance and practical value for the research and application of snake robot and memory wire.

SUMMARY OF THE INVENTION

The purpose of the patent of the present invention is to provide an electronically controlled shape memory alloy wire to control the movement of a snake robot. It can be realized by pulling a snake body joint of the snake robot by four memory alloy wires.

In order to solve the above-mentioned technical problems, the patent of the present invention adopts the following technical solutions:

A snake body joint is composed of four universal joints and four shape memory alloy wires, and an insulating film is covered on the surface of the memory alloy wires to prevent the memory alloy wires from directly contacting the metal universal joints and short-circuiting. Drill holes around the universal joint. The drilling method is shown in Figure 1. Drill holes in the four directions of A, B, C, and D. Drill holes A and C. Hole B is at a certain angle to the bottom surface of the universal joint. , so that the hole is pierced below point E (as shown in Figure 2), and the drilling method of point D is the same as that of point B. Grind the edge of the hole smooth to reduce the wear caused by the excessive friction between the memory wire and the universal joint when the memory wire is stretched. Each universal joint is connected to form a joint of the overall snake body, and the connection method is shown in Figure 3.

A snake-body joint of the snake-like robot is driven by four long memory alloy wires. As shown in the figure, the wire 1 passes through the holes 101, 102, 103 (104), 105, 106 (107), 108, 109 respectively

(110), 111, 112. The wire 1 is fixed by a screw a at the end of a snake body joint. The wires 2 pass through the holes 201 , 202 , 203 ( 204 ), 205 , 206 ( 207 ), 208 , 209 ( 210 ), 211 , and 212 respectively. The wire 2 is fixed by a screw b at the end of a snake body joint. Wires 3 and 4 are perforated in the same way as 1 and 2, pass through the joint, and are fixed by screws c and d, respectively, at the joint end. After removing the insulating film, one end of the wire is fixed with the universal joint of the joint head to form a circuit. Drill four threaded holes at the end of a gimbal of the joint head, pass the wire through the four holes of the gimbal at the end, and screw four screws (a, b, c, d) with appropriate lengths into the threaded holes , and fasten the wire to the joint head. The ends of the four wires are respectively connected to four different positive poles of the electronic control device, the joint of the universal joint snake body is connected to the negative pole of the electronic control device, and one joint of the snake robot forms a complete closed circuit. When the robot needs to perform complex movements, multiple snake body joints can be used, and multiple snake body joints are connected to form the entire snake-shaped robot. Each joint is controlled by a power controller, and the medium performs different steering movements to achieve complex movements.

The positive pole of the electronic control device is divided into four parts, and each part controls the current of a wire. By changing the current input to the four parts, the current passing through the wire is different, and the shape variables of the four wires are different, which makes the snake-shaped robot The motion state of one of the joints changes. By changing the currents in the multiple joint wires, the motion state of the entire snake-like robot changes greatly.

Description of drawings

Figure 1: Schematic diagram of universal joint drilling

Figure 2: Cutaway view of the inclined hole of the universal joint

Figure 3: Schematic diagram of a snake body joint

Figure 4: Steering Flowchart

Detailed ways

Below in conjunction with accompanying drawing, the patent of the present invention is described in detail below:

Referring to Figure 3, the device is a memory alloy wire-driven snake-shaped robot. Four universal joints are connected one by one, in which a power controller is connected at the end through four wires, and the above devices together constitute a snake body joint. Memory alloy wire 1 passes through holes 101, 102, 103 (104), 105, 106 (107), 108, 109 (110), 111, 112, and metal wire 2 passes through holes 201, 202, 203 (204), 205, 206

(207), 208, 209 (210), 211, 212. The alloy wires 1 and 2 at the head of the snake body joint are fixed by screws and connected to the negative pole of the electronic control device. The wire connection method of 3 and 4 is the same as that of 1 and 2. The negative pole of the electronic control device is connected back to the electronic control device through a wire on the outside of the snake body joint. The memory alloy wires 1, 2, 3 and 4 are respectively connected to the four positive electrodes of the electronic control device at the tail of the snake body joint. When the snake robot is required to turn to the left, first reduce the current in 3 to reduce the amount of contraction, and then increase the current in 1 to increase the amount of contraction. At the same time, adjust the current in the wires 2 and 4 to change the amount of expansion and contraction to prevent interference with the left and right steering of the robot. The metal wires 1 and 3 form a certain displacement difference, which makes the snake body gimbal rotate. The above four steps are realized by the electronic control device to complete the left turn of the wire, and the same is true for the right turn. The turning process of the snake robot is shown in Figure 4.

When turning up and down, first reduce the current in 2 to reduce the shrinkage, and then increase the current in 4 to increase the shrinkage. At the same time, adjust the current in the wires 1 and 3 to change the amount of expansion and contraction to prevent interference with the robot's up and down turning. The metal wires 2 and 4 form a certain displacement difference, so that the snake body universal joint completes the upward rotation. Rotate down in the same way. Simple up and down and left and right rotation of a single snake body joint, each snake body joint constitutes a complex snake-shaped robot motion.

The above examples illustrate the technical concept and structural features of the patent of the present invention, and the purpose is to make the scientific research personnel and engineering technicians who conduct research work in this field understand the patent of the present invention and realize the product accordingly.

Claims (3)

1. An electrically controlled shape memory alloy wire snake-shaped robot is characterized in that: the snake body joint is composed of a plurality of snake body joints, and each snake body joint mainly comprises a universal joint (I, II, III and IV), screws (a, b, c and d), shape memory alloy wires (1, 2, 3 and 4), a power supply controller (5) and the like.

2. The electrically controlled shape memory alloy wire snake robot of claim 1, wherein: for each snake body joint, four anodes and a cathode are led out from the power supply controller (5), the four anodes are respectively connected with 4 different metal wires (1), (2), (3) and (4), and the cathode is connected with the universal joint snake body joint. The metal wire (1) is connected with the metal snake body joints through the holes 101, 102, 103, (104), 105, 106, (107), 108, 109, (110), 111 and 112, is fixed by a screw a at the tail end of the snake body joint, the connection mode of the metal wire (3) is the same as that of the metal wire (1), the metal wire (2) is connected with the metal snake body joints through the holes 201, 202, 203, (204), 205, 206, (207), 208, 209, (210), 211 and 212, is fixed by b at the tail end of the snake body joint, the connection mode of the metal wire (4) and the metal wire (2) is the same, and the metal wire is connected with the metal snake body joints by screws at the tail end of the metal wire to form a complete closed loop.

3. The steering section of an electrically controlled shape memory alloy wire snake robot of claim 2, wherein: four memory alloy wires are used for controlling the steering of each snake body joint, so that the complex motion of the snake-shaped robot is realized. For each joint, when the joint needs to turn to the right, the current in the wire (1) is increased, the current in the wire (3) is reduced, the wire (1) is shortened, and the universal joint snake body joint is deviated to the side where the holes 101, 102, 103, (104), 105, 106, (107), 108, 109, (110), 111 and 112 are located, so that the right turn is completed. The principle of left turn is the same as right turn. When the joint needs to be turned upwards, the current in the wire (2) is increased, the current in the wire (4) is reduced, the wire (2) is shortened, and the universal joint snake body joint is deviated to the side where the holes 201, 202, 203, (204), 205, 206, (207), 208, 209, (210), 211 and 212 are located, so that the upper turning is completed. The down-rotation principle is the same as the up-rotation. The up-and-down rotation and the left-and-right rotation of each snake body joint jointly form the complex motion of the snake-shaped robot.

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