A Novel Method of Motion Planning for an Anthropomorphic Arm Based on Movement Primitives

Abstract

Motion planning for an anthropomorphic arm is discussed in this paper. A three-level motion planning framework “joint space—movement primitive space—task space” is established by introducing movement primitives as the bridge connecting the task space and joint space. The proposed method cannot only control the motion process of an anthropomorphic arm, but also simplify the motion planning of complicated operation tasks. On the basis of this, a specific human arm triangle model is proposed as an instantiation of the abstract movement primitive to describe the motion state of the anthropomorphic arm. Through introducing the concept of working plane, the forward and inverse kinematics among joint space, human arm triangle space, and task space are derived by coordinate transformation and geometric analysis. And then, the joint trajectories of two fundamental movement primitives based on the human arm triangle, including motion of moving on the working plane and self-motion of switching working plane, are obtained by solving differential equations. Finally, the validation and feasibility of the proposed method are verified by one simulation comparison with a traditional method and two real experiments.