Design, Reachability Analysis, and Constrained Motion Planning for a Quadcopter Manipulator System

Abstract

View Video Presentation: https://doi.org/10.2514/6.2022-0269.vid This paper presents a detailed workspace analysis of an aerial robot and a motion planning algorithm to generate the robotic arm's feasible motion in the reachable workspace. An aerial robot consists of a quadcopter and a three degree of freedom manipulator attached to the bottom of the aerial vehicle. The quadcopter-manipulator system can reach otherwise hard-to-reach locations, and the manipulator can perform different tasks. Serial link manipulators have a larger workspace and relatively uncomplicated kinematics. In the proposed system, the manipulator's workspace is constrained due to various factors like the downwash of the drone, torque limits, singular configurations, and mechanical structure. The effect of these factors on the reachable workspace is analytically studied in this work. Based on the constraints, a reachable workspace is derived. Finally, a motion planning algorithm that considers these constraints and generates feasible arm configurations is developed. A minimum acceleration trajectory is then generated to reach a given target location. The proposed motion planning algorithm is implemented on the quadcopter manipulator system's unified dynamics, simulated, and validated in MATLAB and ROS/Gazebo platform.