Design And Handoff Operation Planning Of Dual-arm Collaborative Robot

With the world's aging population,the hardware platform of dual-arm collaborative robot and dual-arm collaborative technology are gradually becoming research hot spot in the field of robotics.Because it can work instead of worker and has very important research and application value.This article introduces the dual-arm collaborative robot prototype platform independently developed.And I focus on the problem of handoff operation planning in this article.The main research contents are as follows:Firstly,the overall scheme design of the dual-arm collaborative robot was designed according to the functional requirements including the structural design of the mobile chassis,manipulators,waist rotation unit,gimbal and so on.The hardware selection,construction and debugging was performed.The software and hardware control system of the robot was designed.The forward and inverse kinematics of the dual-arm system and the working space are analyzed.For the inverse problem of redundant manipulator,we used the parameterized joint angle to obtain a closed solution for derivation.And the IK-fast plug-in was generated to solve the problem of kinematics calculation in software system.The Monte Carlo random sampling algorithm was used to analyze the working space of single arm and the collaborative working space of dual-arm.We verified in matlab.Secondly,dual-arm cooperation motion was studied.At the beginning,the trajectory planning methods of the single manipulator in cartesian space was analyzed in detail.The coordinated motion of the dual-arm was divided into loose coordinated motion and tight coordinated motion according to the different task requirements.The kinematics model of the dual-arm system was used to analyze the kinematics constraints such as the posture and speed of the two robotics manipulators in different motion modes.At the same time,we proposed an implementation method of tightly coordinated motion with two robotic manipulators based on the master-slave motion mode in order to ensure the stability and consistency of the dual-arm's movement.Simulation environment was set up in the ROS and the algorithm was verified by simulation experiments.Then,the problem of dual-arm handoff operation planning was studied.This paper proposed an optimization method of the handoff location selecting and path planning.By analyzing the handoff process,the optimization model of handoff location was established for the dual-arm robot.Thus the handoff location selecting problem transformed into a nonlinear constraint optimization problem.Using the improved genetic algorithm,the optimization handoff location was selected.The RRT*-Connected algorithm was studied.And this algorithm was also used to plan the collision-free path of the dual-arm during the handoff operation process.To solve the non-repeatable problem of the random sampling algorithm,the saved historical planning information was used to find the shortest-consuming path.In this way,the dual-arm can reach the handoff location in a short time to complete the transfer operation.This method was verified in a simulation environmentFinally,the experiments were performed to verify the performance of the hardware platform,software system and various algorithms proposed in this article based on self-developed robot.Inverse kinematics solution experiments,trajectory planning experiments,dual-arm loose coordinated motion experiments,handoff objects between arms and water pouring service experiments were performed.The experimental results prove the effectiveness of the algorithm proposed in this paper and the reliability of the dual-arm collaborative robot prototype platform.