Research On Trajectory Planning Of Wire Driven Hyper-Redundant Manipulator

With the flourishing development of aviation,aerospace,and nuclear power industries,the demand for daily maintenance and repair of equipment such as large spacecraft,airplanes,and nuclear facilities is increasing.However,due to narrow workspaces and harsh environments,these tasks have become exceptionally difficult.Hyper-redundant manipulator have the characteristics of multiple degrees of freedom,which makes them highly flexible,powerful in obstacle avoidance,and fault-tolerant,and they have a wide range of application prospects.At the same time,the high degrees of freedom of the hyper-redundant manipulator also pose great challenges for research on motion planning and other issues.This article focuses on the poor controllability and reliability of existing ground robots for narrow environment detection,as well as their poor autonomous motion capability.In combination with the requirements of narrow space and complex environment detection monitoring tasks,the following work is mainly carried out:(1)Build the structural model of the line-driven hyper-redundant manipulator and analyze its kinematics.The mechanical arm is designed with an elephant trunk structure and is driven by ropes.It is composed of ten bionic joints connected in series by universal joints.There are20 degrees of freedom in total and controlled by 30 driving ropes.On the basis of the structural design,the modeling of the manipulator is carried out by the D-H parameter method.Firstly,the single joint analysis is completed,and then the kinematic analysis of the whole arm is completed by the chain rule.In order to solve the problem that the inverse kinematics of the hyper-redundant manipulator is difficult to solve,the ridge line method is introduced to convert the problem of inverse kinematics into the problem of determining the position points of each joint.(2)Establish a hyper-redundant manipulator motion control algorithm.Aiming at the problems of large number of joints and excessive calculation amount of hyper-redundant manipulator,a motion control algorithm based on goal guidance is proposed.Further,in order to solve the problem of precision in the motion process of the hyper-redundant manipulator,a vision-based joint position compensation algorithm of the manipulator is proposed.By locating the Aruco identification code,and then calculating the angle of each universal joint,the closed-loop control of visual feedback ensures the accuracy of the pose of the robot arm,making it have higher motion accuracy.(3)The trajectory planning algorithm based on the "head" traction concept.In the motion of a hyper-Redundant Manipulator,its excellent bending performance can be utilized to adapt to complex environmental conditions.The redundant degrees of freedom have more solution space and optimization goals in trajectory planning.To address the problem of large calculation amounts and poor obstacle avoidance effects in motion planning for hyperRedundant Manipulator in complex spatial environments,a "head traction" trajectory planning method is designed by imitating the motion process of snakes.The linear-driven hyperRedundant Manipulator can efficiently move in complex terrain along the planned path using this method.(4)Prototype construction and experiment of hyper-redundant manipulator.Design the control system to build a physical prototype,and complete the experimental verification and performance analysis of the typical motion of the wire-driven hyper-redundant manipulator,visual closed-loop,and spatial obstacle avoidance.The experimental results verify that the prototype of the hyper-redundant manipulator designed in this paper has a reasonable structure,correct kinematics analysis,high-efficiency motion control algorithm,and the ability to accurately control and avoid obstacles in actual engineering applications.