Linear motor based multi-channel driven flexible manipulator

Abstract

This invention discloses a line-driven flexible robotic arm based on a multi-channel linear module, comprising a drive module, an arm telescopic mechanism, and a universal joint. The drive module includes a bracket, a driver, a lead screw, and a slider. The arm telescopic mechanism includes a housing, a stator, a rotor, a lead screw, and an inner rod. The stator is fixed to the housing, and the rotor is located inside the stator. The rotor drives the lead screw, thereby causing the inner rod to telescopically extend and retract. The universal joint includes a first joint seat, a cross shaft, a second joint seat, and a locking structure. The first joint seat is hinged to the second joint seat via the cross shaft. One end of a cable is fixedly connected to the slider, and the other end passes through the first joint seat and is fixed to the second joint seat. This invention achieves complete rear-mounting of the core drive components, and realizes electrically controlled telescopic extension and retraction of the inner rod through the integrated structure of the stator, rotor, and lead screw, thereby increasing the reachability of spatial depth and reducing end-effector inertia. The cross shaft provides stable and reliable multi-degree-of-freedom deflection, eliminating clue entanglement and slippage errors, and improving the end-effector servo accuracy under depth visual positioning, perfectly meeting the needs of obstacle avoidance and non-destructive harvesting operations within dense tree canopies.

Description

Technical Field

[0001] This invention relates to the field of robotics and automated harvesting equipment technology, and in particular to a line-driven flexible robotic arm based on a multi-channel linear module. Background Technology

[0002] With the development of intelligent agriculture, the application of harvesting robots is becoming increasingly widespread. Especially in the harvesting of tropical fruits growing in dense canopies, the target fruits are often located within complex, unstructured canopies and face severe obstruction from branches and leaves. Existing rigid robotic arms typically mount large motors directly at each joint, resulting in excessive end-effector mass and high inertia. In the complex environment of dense foliage, the large and rigid robotic arm is prone to interference and collisions with surrounding branches, making it difficult to accurately identify and grasp fruits and branches, and easily causing mechanical damage. Therefore, there is an urgent need for a line-driven flexible robotic arm capable of long-distance transmission of driving force, axial extension and retraction adjustment within an internally controlled electrical space, extremely lightweight end-effector, and flexible obstacle avoidance and maneuvering. Summary of the Invention

[0003] The purpose of this invention is to provide a line-driven flexible robotic arm based on a multi-channel linear module, in order to solve the problems mentioned in the background art, such as the large end mass of existing rigid robotic arms, difficulty in flexibly avoiding obstacles in complex canopy environments, and limited spatial telescopic operating radius.

[0004] To achieve the above objectives, the present invention provides the following technical solution: A line-driven flexible robotic arm based on a multi-channel linear module, comprising: a drive module, an arm telescopic mechanism, and a universal joint; the drive module includes a bracket, a driver mounted on the bracket, a lead screw driven by the driver, and a slider sleeved on the lead screw; the arm telescopic mechanism includes a housing, a stator, a rotor, a lead screw, and an inner rod, the stator being fixedly connected to the housing, the rotor being rotatably mounted within the stator, the lead screw being driven by the rotor, and the lead screw driving the inner rod to extend and retract axially; the universal joint includes a first joint seat, a cross shaft, a second joint seat, and a locking structure, the first joint seat being hinged to the second joint seat via the cross shaft, and the locking structure being used to lock the relative rotation between the first joint seat and the second joint seat when there is no driving force; the robotic arm also includes multiple cables, one end of which is fixedly connected to the corresponding slider, and the other end passes through the first joint seat and is fixedly connected to the second joint seat.

[0005] The number of drivers is multiple and they are installed side by side on the bracket. Each driver drives one lead screw and one slider.

[0006] The cables are distributed on the outer surface of the housing and move in conjunction with the extension and retraction of the inner rod.

[0007] The first joint seat has a cable guide channel, through which the cable passes without obstruction.

[0008] The central cross-shaped journal of the cross shaft is rotatably connected to the first joint seat and the second joint seat respectively, and there are two locking structures, which are respectively installed on the first joint seat and the second joint seat.

[0009] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention realizes the complete rearward placement of the core drive components, and constructs an independent internal rod telescopic power source through the stator, rotor and lead screw integrated in the shell, which gives the robotic arm a stronger depth reach range and active obstacle avoidance fine adjustment performance; at the same time, it greatly reduces the end motion inertia, reduces the destructive force when colliding with branches, and uses the cross axis to provide stable and reliable multi-degree-of-freedom deflection, eliminates the error of clue entanglement and slippage, and improves the end servo accuracy under depth vision positioning, perfectly meeting the needs of obstacle avoidance and non-destructive harvesting operations in dense tree canopy. Attached Figure Description

[0010] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0011] Figure 1 This is a schematic diagram of the overall assembly structure of the present invention.

[0012] Figure 2 This is a perspective view of the boom telescopic mechanism and the universal joint.

[0013] Figure label:

[0014] 1-Driver, 2-Slider, 3-Bracket, 4-Lead screw, 5-Cable, 6-Inner rod, 7-Outer shell, 8-Stator, 9-First joint seat, 10-Cross shaft, 11-Locking structure, 12-Second joint seat, 13-Lead screw, 14-Rotor. Detailed Implementation

[0015] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0016] In the description of this invention, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. Furthermore, in the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0017] Please see Figure 1 and Figure 2 This invention provides a line-driven flexible robotic arm based on a multi-channel linear module. The robotic arm mainly consists of a drive module, a telescopic arm mechanism, and a universal joint.

[0018] The drive module is mounted on the base of the robotic arm and includes a bracket 3, a driver 1 mounted on the bracket 3, a lead screw 4 connected to the driver 1, and a slider 2 sleeved on the lead screw 4. Multiple drivers 1 are mounted side-by-side on the bracket 3, and each driver 1 independently controls one lead screw 4 and one slider 2. During robotic arm posture adjustment, the multiple drivers 1 receive pulse commands and rotate, driving the lead screw 4 to rotate. This efficiently converts the rotational power of the motor into high-precision linear displacement of the slider 2. Through the independent linear reciprocating motion of the multiple sliders 2, precise and controllable axial displacement and tension are applied to the cable 5 connected to them.

[0019] The boom telescopic mechanism is connected to the drive module and includes a housing 7, a stator 8, and such as Figure 2 The rotor 14, lead screw 13, and inner rod 6 are coaxially arranged inside the housing 7. The stator 8 is fixedly connected to the housing 7, the rotor 14 is rotatably disposed within the stator 8, and the lead screw 13 is drively connected to the rotor 14. When the arm telescopic mechanism performs axial telescopic action, the stator 8 is energized to generate an electromagnetic field that causes the rotor 14 to rotate. The rotor 14 directly drives the lead screw 13 to rotate synchronously. Through a threaded transmission mechanism, the rotational motion is converted into linear driving force, which drives the inner rod 6 to smoothly reciprocate and slide along the axial direction inside the housing 7. This allows for real-time adjustment of the depth that the front end of the robotic arm can reach into complex unstructured environments such as dense tree canopies. Multiple cables 5 are evenly distributed on the outer surface of the housing 7 and move axially in conjunction with the telescopic movement of the inner rod 6.

[0020] The universal joint is located at the actuator end of the robotic arm and is used to support the end effector and flexibly adjust its working posture. It mainly includes a first joint seat 9, a cross shaft 10, a second joint seat 12, and a locking structure 11. The first joint seat 9 is hinged to the second joint seat 12 via the cross shaft 10. The cross shaft 10 connects the first joint seat 9 and the second joint seat 12 via its mutually orthogonal journals, thereby eliminating axial torsional deformation of the end effector from a physical geometric perspective and providing high-precision pitch and yaw degrees of freedom. The first joint seat 9 has a cable guide channel. One end of the cable 5 is fixedly connected to the slider 2, and the other end passes unobstructed through the guide channel of the first joint seat 9 and connects to the second joint seat 12. When multiple cables 5 generate different tension differences under the traction of the drive module, the tension difference acts directly on the second joint seat 12 through the guide channel, enabling it to complete high-precision, omnidirectional, and flexible deflection around the center point of the cross shaft 10 in three-dimensional space. Two locking structures 11 are respectively located at the first joint seat 9 and the second joint seat 12. When the drive system is powered off, has no driving force, or stops operating, the locking structure 11 is activated to lock the relative rotation between the first joint seat 9 and the second joint seat 12, achieving effective self-locking and reliable maintenance of the end-effector's posture, and avoiding disorderly shaking of the flexible wire drive when it loses tension. The power source of this device is completely rear-mounted and has electrically controlled axial extension and retraction, high-precision deflection, and power-off self-locking functions. The robotic arm can move extremely lightly through dense tree canopies, perfectly meeting the needs of obstacle avoidance and damage-free harvesting in complex orchard environments.

[0021] The above description discloses only one preferred embodiment of the present invention, and should not be construed as limiting the scope of the present invention. Those skilled in the art will understand that all or part of the processes of the above embodiments can be implemented, and equivalent changes made in accordance with the claims of the present invention are still within the scope of the invention.

Claims

1. A line-driven flexible robotic arm based on a multi-channel linear module, characterized in that, include: The system comprises a drive module, a telescopic arm mechanism, and a universal joint. The drive module includes a bracket, a driver mounted on the bracket, a lead screw connected to the driver, and a slider sleeved on the lead screw. The telescopic arm mechanism includes a housing, a stator, a rotor, a lead screw, and an inner rod. The stator is fixedly connected to the housing, the rotor is rotatably disposed within the stator, and the lead screw is connected to the rotor, driving the inner rod to extend and retract axially. The universal joint includes a first joint seat, a cross shaft, a second joint seat, and a locking structure. The first joint seat is hinged to the second joint seat via the cross shaft. The locking structure is used to lock the relative rotation between the first and second joint seats when there is no driving force. The line-driven flexible robotic arm also includes multiple cables, one end of which is fixedly connected to the corresponding slider, and the other end passes through the first joint seat and is fixedly connected to the second joint seat.

2. The line-driven flexible robotic arm based on a multi-channel linear module according to claim 1, characterized in that, The number of drivers is multiple and they are mounted side by side on the bracket. Each driver drives one lead screw and one slider.

3. The line-driven flexible robotic arm based on a multi-channel linear module according to claim 1, characterized in that, The cables are distributed on the outer surface of the housing and move in conjunction with the extension and retraction of the inner rod.

4. A line-driven flexible robotic arm based on a multi-channel linear module according to claim 1, characterized in that, The first joint seat has a cable guide channel, through which the cable passes without obstruction.

5. A line-driven flexible robotic arm based on a multi-channel linear module according to claim 1, characterized in that, The central cross-shaped journal of the cross shaft is rotatably connected to the first joint seat and the second joint seat respectively. There are two locking structures, which are respectively installed on the first joint seat and the second joint seat.

6. A line-driven flexible robotic arm based on a multi-channel linear module according to claim 1, characterized in that, The front end of the second joint seat is suitable for mounting a mechanical gripper or a cascaded boom telescopic mechanism to assist in the gripping and separation of the target fruit.

Images