With the rapid development of modern industry,the role of robots in the industrial field has become more and more obvious,and the research enthusiasm about industrial robots is also increasing.Among them,path planning technology has always been a hot spot in the research of industrial robots,and plays an important role in the development of industrial robots.This paper takes the six-degree-of-freedom manipulator widely used in the industrial field as the research object,and conducts research on the collision detection problem of the manipulator.According to the basic principles and mathematical model of the ant colony algorithm,the deficiencies in the basic ant colony algorithm are improved,and the research object and the collision detection algorithm are combined to realize the obstacle avoidance path planning of the six-degree-of-freedom manipulator in space.The main work of the thesis is as follows:(1)The first chapter briefly explains the research background and research significance of the subject,and introduces the current research status in the field of robotic arm path planning at home and abroad.(2)The second chapter studies and analyzes the forward and inverse kinematics of the robotic arm.The standard D_H notation and the improved D_H notation are introduced respectively,and the improved D_H method,which is more widely applicable,is used to establish the joint coordinate system of the manipulator,and the solution of the forward and inverse kinematics equations of the researched manipulator is gradually calculated.Since the inverse kinematics solution may have multiple solutions,it is proposed to select a set of optimal solutions by adopting the principle of the smallest sum of rotation angle changes of each joint.Taking the IRB2400 model manipulator produced by ABB as an example,the manipulator model is established through Robotics Toolbox in the MATLAB platform to verify the correctness of the forward and inverse kinematics solution equations.(3)The third chapter studies the collision detection problem in the path planning of the manipulator.The basic idea is to use regular-shaped geometric bodies to envelop the linkages and obstacles of the robotic arm to simplify the detection model.According to the structural characteristics of the mechanical arm,its connecting rod is wrapped with a suitable cylinder,and the obstacle is wrapped with a sphere with a suitable radius.In order to simplify the calculation process,the linkage of the robotic arm is further abstracted into line segments,and the method of "expanding obstacles" is adopted to superimpose the maximum radius of the linkage of the robotic arm on the radius of the obstacle sphere,thereby connecting the robotic arm to the obstacle.The collision detection problem of is simplified to the problem of judging whether the line segment in the space intersects the sphere.(4)The fourth chapter proposes improvements to the ant colony algorithm based on the research object.Briefly explain the principle and mathematical model of the ant colony algorithm,and take the TSP problem as an example to study the selection of relevant parameters of the algorithm.Aiming at the defects of the algorithm,the ant colony algorithm is improved,which mainly includes the uneven distribution of the initial pheromone,the introduction of safety factors in the heuristic function,the optimization of the weight factors α and β,and the dynamic adjustment of the pheromone volatilization coefficient Etc.,improve the comprehensive performance of the algorithm and apply it to the space path planning of the six-degree-of-freedom manipulator.(5)The fifth chapter designs experimental schemes and conducts simulation experiments.Modeling and designing experimental programs in MATLAB,using the basic ant colony algorithm,the improved ant colony algorithm in this paper and the algorithms in other documents to carry out the obstacle avoidance path planning experiment of the manipulator.Comparing the simulation results under the same environment proves the advantages of the improved algorithm in the article.Finally,perform kinematics simulation in Robot Studio software according to the path planning results to check whether the end effector of the robotic arm collides with obstacles when moving along the planned path,and verify the safety of the planned path. |