Multidisciplinary methodology to predict the performance of modular actuator-based manipulator

In this paper, we propose a multidisciplinary methodology to predict the performance of a modular actuator-based robotic manipulator considering the flexibilities of the linkage and the joint. Generally, fast dynamics of manipulator caused by structural flexibility often leads to the residual vibrations and deflections. However, it is quite difficult to predict these types of phenomena analytically since the dynamic characteristics of the manipulator considerably vary with its posture. To address this issue effectively, we propose to utilize the finite element method as well as the Lagrange formulation for more accurate modeling of the mechanical flexibility in manipulator structure. To verify the viability of proposed method, we perform the simulation using a 3 degree-of-freedom (DOF) planar manipulator constructed with three modular actuators. Through the simulation, the sensitivity analysis and principal component analysis (PCA) are carried out for the settling time and deflection with respect to the motion profile and end effector position. It is observed that the structural flexibility of the link and flexibility of modular actuator originated from the harmonic drive as well as the end effector position have a significant effect on the settling time and the deflection. The parameters in the S-curve motion profile are other key factors to the motion time and settling time, which should be selected to minimize the cycle time for task completion.