Collision-free Motion Planning Of 7-DOF Manipulator In Intelligent Human-robot Co-piloting Flight

In the intelligent human-robot co-piloting flight system,the manipulator replaces the co-pilot and assists the pilot to complete various flight tasks.In order to prevent the collision between the manipulator and the environment or the crew,it is necessary for the manipulator to be able to avoid obstacles during the movement,so as to ensure the safety during the flight.In this paper,a motion planning simulation system for a 7-DOF manipulator is designed based on Robot Operating System(ROS).Universal Robot Description Format(URDF)file is used to describe the LBR iiwa 7-DOF manipulator,and visual modeling of the manipulator is completed through Rviz.By configuring Moveit! Packages,Moveit! is built.The Gazebo simulator is used to realize the physical simulation of the manipulator.The joint trajectory control interface between the motion planning platform and the physical simulator is designed,which connects Moveit! and Gazebo simulation system.Then,the D-H parameter method was used to establish the kinematics model of LBR iiwa 7-DOF manipulator,and the forward and reverse kinematics of the manipulator were analyzed.Then the forward and reverse kinematics equations were established respectively.Through the theoretical analysis of cartesian space linear trajectory planning,and the simulation experiment of interpolation motion of the end trajectory of the manipulator in the simulation system,the correctness of kinematics analysis of the manipulator is verified.Then the basic theory of robot motion planning is studied and the RRT algorithm based on random sampling is analyzed.In view of the shortcomings of the basic RRT algorithm,some improvements on node expansion are proposed,which enhances the orientation of RRT algorithm and improves the plannin g efficiency of the algorithm.Experimental results show that the improved RRT algorithm is effective and advanced.Finally,Kinect is used in the simulation system to obtain 3 D point cloud information around the manipulator,and the 3D point cloud is conv erted into Octo Map.In this paper,Octo Map environmental information is used to realize the collision detection of the manipulator,and RRT planning algorithm is further used to complete the motion planning.Through the customization of obstacle environment in Gazebo and the introduction of 3D point cloud environment of the aircraft cockpit,simulation experiments of motion planning were carried out respectively,which verified the excellent algorithm performance of the improved RRT planning algorithm on the 7-DOF manipulator platform and its practicability in the intelligent human-robot co-piloting flight system.