Line-driven flexible high-redundancy mechanical arm

Abstract

The utility model discloses a line-driven flexible high-redundancy mechanical arm which comprises a mechanical arm profile frame, a steering engine driving system, a spring pre-tightening system, a mechanical arm body and a clamping jaw, the steering engine driving system comprises a bus steering engine and a wire coil, the mechanical arm body comprises a plurality of mechanical arm joints which are connected step by step, and the clamping jaw is arranged at the tail end of the mechanical arm body; steel wire ropes wound on the wire coil are connected with the mechanical arm joints after being pre-tightened through the spring pre-tightening system, and one steel wire rope is fixed to each of the two sides of each joint and driven by one bus steering engine. Compared with a traditional mechanical arm, the mechanical arm has the advantages of being light in weight, high in degree of freedom, high in anti-interference capacity and the like, and can meet the working requirements of various special environments.

Description

Technical Field

[0001] The utility model relates to the technical field of robots, in particular to a novel line-driven flexible high-redundancy mechanical arm. Background Art

[0002] At present, the application of flexible high-redundancy manipulators in various fields is gradually increasing, and different mission scenarios have different requirements for the functions of the manipulator. The wire-controlled flexible high-redundancy manipulator has obvious advantages over the traditional servo-driven manipulator. Since the servo is not directly installed on the manipulator, the manipulator structure is lighter. This design reduces the mass of the manipulator itself, improves the overall flexibility and maneuverability, and makes it more suitable for work scenarios that require fast response and flexible operation.

[0003] In addition, the wire-controlled robotic arm has strong anti-interference ability because it does not rely on the servo to directly transmit power. Traditional robotic arms may be affected by electromagnetic interference or other external interference, but the structure of the wire-controlled flexible robotic arm can effectively reduce the impact of these interferences on its motion performance, improving the stability and reliability of the system. This makes the wire-controlled flexible robotic arm perform better in complex environments and is more suitable for practical applications in various industrial and service scenarios. Utility Model Content

[0004] In view of the problems existing in the prior art, the utility model aims to provide a wire-driven flexible high-redundancy mechanical arm with an improved structure.

[0005] To achieve the above-mentioned purpose, the utility model discloses a wire-driven flexible high-redundancy robotic arm, comprising a robotic arm profile frame, a steering gear drive system, a spring pretensioning system, a robotic arm body and a clamping claw. The steering gear drive system comprises a bus steering gear and a wire drum. The robotic arm body comprises a plurality of robotic arm joints connected in stages, at the end of which the clamping claw is arranged. The steel wire rope wound on the wire drum is pretensioned by the spring pretensioning system and then connected to the robotic arm joint. A steel wire rope is fixed on both sides of each joint, and the joint is driven by a bus steering gear.

[0006] Furthermore, the steering gear drive system includes nine 20KG / CM bus single-axis steering gears and nine wire drums for winding steel wire ropes.

[0007] Furthermore, the spring preload system includes eight repeated subsystems, each of which includes a pair of movable pulleys installed with springs and a pair of fixed pulleys, and the elastic force of the springs provides basic preload force for each wire rope; the robotic arm body includes eight robotic arm joints.

[0008] Furthermore, nine bus single-axis steering gears correspond to the eight subsystems and the clamps respectively and are connected and driven by steel wire ropes.

[0009] Furthermore, the robotic arm joints are designed with limited positions to ensure that the maximum rotation angle of each robotic arm joint relative to the previous joint is 45°.

[0010] Furthermore, an IMU attitude sensor installation position is reserved on the mechanical arm joint, and an IMU attitude sensor is installed on every two adjacent mechanical arm joints.

[0011] Furthermore, the wire drum is used to wind a pair of corresponding steel wire ropes to ensure the continuity of the robot arm during movement.

[0012] Furthermore, the robotic arm profile frame is composed of an upper and lower part, the upper part is in a rectangular shape, and the upper and lower parts are assembled and disassembled by profile locks.

[0013] Furthermore, the clamp includes fingers, a clamp base, and a clamp longitudinal moving part, wherein a pin is used to connect the mounting position to the end joint of the robotic arm, and the clamp longitudinal moving part forms a piston structure with the clamp base through four axes to ensure that the clamp moving part can only move longitudinally.

[0014] Furthermore, the clamp includes fingers, the lower outer side of each finger is movably connected to the clamp base through a clamp connecting rod, and the lower inner side of each finger is movably connected to the longitudinal moving part of the clamp. The clamp connecting rod is rotated by pulling the steel wire rope to ensure smooth opening and closing of the fingers.

[0015] Compared with traditional robotic arms, this utility model has the characteristics of light weight, high degree of freedom and strong anti-interference ability, and can meet the requirements of working in various special environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a three-dimensional structural diagram of the utility model;

[0017] Figure 2 It is the three-dimensional structure diagram of the bus servo and the cable drum;

[0018] Figure 3 It is the three-dimensional structure diagram of the spring preload system;

[0019] Figure 4 It is a three-dimensional structure diagram of the joint;

[0020] Figure 5 The three-dimensional structure diagram of the gripper;

[0021] Among them: 1-mechanical arm profile frame; 2-profile lock; 3-profile wire hole; 4-servo drive system; 5-spring preload system; 6-mechanical arm body; 7-gripper; 8-bus servo; 9-cable drum; 10-cable drum wire hole; 11-spring; 12-U-groove movable pulley; 13-U-groove fixed pulley; 14, 15-preload mechanism wire hole; 16-upper mounting position; 17-lower mounting position; 18-wire bundle hole; 19, 20-joint wire hole; 21-IMU mounting position; 22-pin shaft; 23-gripper base; 24-gripper longitudinal moving part; 25-axis; 26-gripper connecting rod; 27-finger; 28, 29-gripper wire hole. DETAILED DESCRIPTION

[0022] The following will be combined with the accompanying drawings to clearly and completely describe the technical solution of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0023] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are 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 limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0024] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0025] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0026] like Figures 1 to 5As shown, the utility model is a line-driven flexible high-redundancy mechanical arm, which includes a mechanical arm profile frame 1, a steering gear drive system 4, a spring preload system 5, a mechanical arm body 6 and a clamp 7.

[0027] The robot arm profile frame 1 is a detachable frame, and the main part can be installed on various machine platforms. The robot arm profile frame 1 consists of two parts, the upper part is a rectangular parallelepiped, and the upper and lower parts can be assembled and disassembled by the profile lock 2.

[0028] In order to constrain the position of the wire rope, some wire passing plates are used. Multiple wire passing plates are installed on the mechanical arm profile frame 1 to constrain the wire rope in a certain position. The bus servo 8 pulls the wire rope through the wire drum and various wire passing plates to control the movement of the mechanical arm joint. The profile wire passing hole 3 at the bottom of the mechanical arm is installed on the profile frame.

[0029] The servo drive system 4 includes nine 20KG / CM bus single-axis servos 8 and nine wire drums 9 for winding steel wire ropes. The servo drive system 4 is installed on both sides, with four and five bus servos on each side respectively. The spring preload system 5 is installed in the upper profile frame. There are a total of eight spring preload subsystems corresponding to eight joints. The clamp 7 has no preload system. The robot body 6 is fixedly mounted on the profile frame through the bottom joint; the clamp 7 is installed on the last joint of the robot arm through a pin.

[0030] See also Figure 2 , the figure shows a schematic diagram of the structure of a bus servo 8 and a cable drum 9 of the servo drive system; two steel wires controlling the movement of a joint pass through the cable holes 10 on the cable drum 9 and are tightened and fixed by screws. The steel wires are wound around the cable drum 9 for several turns to ensure the continuity of the movement process.

[0031] See also Figure 3 The spring preload system 5 includes eight repeated subsystems, each of which includes a pair of spring-mounted movable pulleys 12 and a pair of fixed pulleys 13. The figure shows a subsystem of the spring preload system 5, which provides spring preload force for two drive wire ropes of a joint. The spring preload system 5 uses a combination of fixed pulleys and movable pulleys to provide basic preload force for each drive wire, so that the wire rope is always kept in a taut state when the robot arm moves, reducing the error caused by wire rope relaxation. The spring 11 is installed on the U-groove movable pulley 12, and the U-groove fixed pulley 12 is installed at the bottom to change the movement direction of the wire rope; the spring preload system 5 constrains the movement of the wire rope through the upper wire hole 14 and the lower wire hole 15.

[0032] See also Figure 4The joint uses a pin to connect the upper mounting position 16 and the lower mounting position 17 to ensure that the two adjacent joints can only rotate relative to each other on one plane. There is a wire harness hole 18 at the bottom of the joint. The steel wire rope with a Teflon sleeve is passed through the wire harness hole 18 to ensure that the steel wire rope is on the central axis of the robotic arm during the movement of the robotic arm, reducing the error caused by the lateral movement of the steel wire rope. There are also two wire holes 19, which are responsible for separating the two steel wire ropes required to control the next joint to pull the movement of the next joint. The joint has a mounting position 21 for the IMU attitude sensor and a hole for passing the wire; the joint is also provided with a wire hole 20 for the steel wire rope to drive the joint movement.

[0033] The robot body 6 includes eight robot joints, which are connected in an interlaced manner. Each joint has one rotational degree of freedom, so the entire robot has eight rotational degrees of freedom; two steel wires are fixed on both sides of each joint, which are driven by a bus steering gear 8. The robot joints are designed with limited positions to ensure that the maximum rotation angle of each robot joint relative to the previous joint is 45°. The robot joints are connected by a slotted pin shaft, which is detachable and can flexibly increase or decrease the number of robot joints.

[0034] An IMU attitude sensor installation position 21 is reserved on the joint of the robotic arm. An IMU attitude sensor is installed on every two adjacent robotic arm joints. The attitude signal of the IMU is used as a feedback signal to realize closed-loop control of the robotic arm, thereby reducing the error during the movement of the robotic arm.

[0035] See also Figure 5 The clamp 7 uses a movable mechanical structure and a flexible finger design, which can be adaptively deformed according to the captured object. The clamp 7 includes a finger 27, a clamp base 23, and a clamp longitudinal motion part 24. The clamp includes four fingers 27. The lower outer side of each finger 27 is movably connected to the clamp base 23 through a clamp connecting rod 26, and the lower inner side of each finger 27 is movably connected to the clamp longitudinal motion part 24. The clamp 7 uses a pin 22 to connect the mounting position 21 to the end joint of the mechanical arm; the clamp longitudinal motion part 24 forms a piston structure with the clamp base 23 through four shafts 25 to ensure that the clamp longitudinal motion part 24 can only move longitudinally and prevent lateral movement. The clamp connecting rod 26 is pulled to rotate by a steel wire rope, thereby ensuring the smooth opening and closing of the finger 27. Two steel wire ropes that drive the joint movement pass through the wire hole 28 and are tightened and fixed by screws; the steel wire rope that drives the clamp to open and close passes through the wire hole 29 and is fixed by screws.

[0036] The specific working process of this utility model is as follows:

[0037] Use the computer host to send motion instructions to the nine bus servos. Each bus servo moves according to the instructions, pulling the corresponding wire rope to move, thereby driving the corresponding joint movement to realize the movement of the robot arm. The bus servo that controls the movement of the gripper pulls the wire rope to tighten or relax, realizing the gripping and releasing actions of the gripper. During the movement of the robot arm, the spring preload system 5 always keeps the wire rope in a taut state, ensuring that the wire holes and wire holes at various locations constrain the position of the wire rope, and ensuring the reliable accuracy of the movement of the robot arm; during the movement of the robot arm, the four IMU attitude sensors measure the attitude information of the joints, and transmit the attitude information as a feedback signal to the host computer. The host computer makes adjustments through the closed-loop control algorithm and sends compensation signals to the corresponding bus servos, thereby realizing the entire drive control process.

[0038] Compared with the prior art, the utility model has the following beneficial effects:

[0039] 1. In the utility model, a variety of methods for constraining the position of the wire rope are used: various wire holes, wire holes of the robot arm joints and U-groove pulleys of the spring preload system, which reduce the position deviation during the movement of the robot arm and solve the error caused by the deviation of the wire rope in the existing wire-driven robot arm;

[0040] Put Teflon hard tubes on the appropriate parts of the wire rope to ensure that the wire ropes do not rub against each other, solving the problem of interference between the drive lines of the existing wire-driven manipulator.

[0041] 2. The method of firmly fixing the wire rope and the spring pre-tensioning system ensure that the wire rope is in a taut state under all circumstances, solving the error caused by the loose wire rope during the movement of the existing wire-driven manipulator;

[0042] 3. The robot arm joints, spring preload mechanism, gripper mechanical structure, servo wire reel and various wire plates on the robot arm profile frame are all made of high-strength materials by 3D printing, which not only ensures the high strength of the structure, but also ensures the lightness and strong anti-interference ability of the robot arm.

Claims

1. A wire-driven flexible high-redundancy robotic arm, characterized in that: It includes a mechanical arm profile frame, a steering gear drive system, a spring pre-tensioning system, a mechanical arm body and a clamping claw. The steering gear drive system includes a bus steering gear and a wire drum. The mechanical arm body includes a plurality of mechanical arm joints connected step by step, and the clamping claw is arranged at the end of the wire drum. The steel wire rope wound on the wire drum is pre-tensioned by the spring pre-tensioning system and then connected to the mechanical arm joint. A steel wire rope is fixed on both sides of each joint, and it is driven by a bus steering gear.

2. The wire-driven flexible high-redundancy robotic arm according to claim 1, characterized in that: The steering gear drive system includes nine 20KG / CM bus single-axis steering gears and nine wire drums for winding steel wire ropes.

3. The wire-driven flexible high-redundancy robotic arm according to claim 2, characterized in that: The spring pre-tensioning system includes eight repeated subsystems, each of which includes a pair of movable pulleys installed with springs and a pair of fixed pulleys, and the elastic force of the springs provides basic pre-tensioning force for each wire rope; the mechanical arm body includes eight mechanical arm joints.

4. The wire-driven flexible high-redundancy robotic arm according to claim 3, characterized in that: Nine bus single-axis steering gears correspond to the eight subsystems and the clamps respectively and are connected and driven by steel wire ropes.

5. The wire-driven flexible high-redundancy robotic arm according to claim 3, characterized in that: The mechanical arm joints are designed with limited positions to ensure that the maximum rotation angle of each mechanical arm joint relative to the previous joint is 45°.

6. The wire-driven flexible high-redundancy robot arm according to claim 3, characterized in that: An IMU attitude sensor installation position is reserved on the mechanical arm joint, and an IMU attitude sensor is installed on every two adjacent mechanical arm joints.

7. The wire-driven flexible high-redundancy robotic arm according to claim 2, characterized in that: The wire drum is used to wind a pair of corresponding steel wire ropes to ensure the continuity of the robot arm during movement.

8. The wire-driven flexible high-redundancy robotic arm according to claim 1, characterized in that: The mechanical arm profile frame is composed of an upper and lower part, the upper part is in a rectangular parallelepiped shape, and the upper and lower parts are assembled and disassembled by profile locks.

9. The wire-driven flexible high-redundancy robotic arm according to claim 1, characterized in that: The clamp includes fingers, a clamp base, and a clamp longitudinal motion part, wherein a pin is used to connect the mounting position to the end joint of the robot arm, and the clamp longitudinal motion part forms a piston structure with the clamp base through four axes to ensure that the clamp motion part can only move longitudinally.

10. The wire-driven flexible high-redundancy robot arm according to claim 9, characterized in that: The clamping jaw comprises fingers, the lower outer side of each finger is movably connected to the clamping jaw base through a clamping jaw connecting rod, the lower inner side of each finger is movably connected to the longitudinal moving part of the clamping jaw, and the clamping jaw connecting rod is rotated by pulling the steel wire rope to ensure smooth opening and closing of the fingers.

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