Research On Modular Joint Design And Motion Planning Method For Redundant Manipulator

The rapid development of electronic commerce has brought new demands and great challenges to the traditional warehousing and logistics industry.Under this situation,it is of great significance to improve the intelligent and automatic level of the warehousing and logistical equipment,increase of efficiency for the equipments and realize the humanmachine safely cooperative work.Manipulators are widely applied to sorting and handling in warehousing and logistical work due to it's outstanding operating ability.However,because of the single function and the poor adaptability to the complex work environment,traditional manipulators can only work in the relatively stable working conditions,which makes traditional manipulators hardly meet the working requirements of high efficiency and high intensity in the warehousing and logistics environment.In view of the above mentioned problems,modular concept is adopted in this paper to design the configuration and structure of the redundant manipulator.On the basis of the design of the manipulator,the kinematic analysis of the redundant manipulator is carried out.After that,the improved rapidly-exploring random trees is adopted in the research of the manipulator's motion planning in complex work scenarios.The main contents of this paper are as follows:(1)According to requirements of warehousing and logistics operation,the configuration and design parameters of the redundant manipulator are analyzed and calculated.On the basis of the definitized parameters and configuration,the selection of the components of the manipulator is determined and the structure of the manipulator joint is designed.In order to ensure the mechanical parts can meet the work requirements,the static analysis is carried out by finite element method.(2)Forward kinematics model of the designed manipulator is carried out by D-H method.Then,the analytical inverse kinematic solution based on the “arm angle” is adopted for the 7 Do F manipulator inverse kinematics analysis.On the basis of the forward kinematic model,the working space of the manipulastor is analyzed and simulated with the method of Monte-Carlo.(3)In order to improve the planning efficiency and reduce the planning time,the goalbias strategy and heuristic information are introduced into basic rapidly-exploring random trees.Based on the improved RRT planning algorithm,obstacle avoidance motion planning of manipulator in configuration space is analyzed in this paper.(4)The manipulator prototype is fabricated and assembled,and the experiment platform is built to test the manipulator joint module performance.To verify the effectiveness of the improved planning algorithm,simulation model of the designed manipulator is built in robot operating system and physical simulator: Gazebo.Then the motion planning simulation experiment of the redundant manipulator is conducted to prove that the improved algorithm is effective.