A Systematic Method for the Design of Piezostack Actuator Integrated Robots for High-Speed and Precision Operation

The operating speed and precision of robot manipulators are limited by the dynamic response limitations of their actuators. The kinematics and dynamics of robot manipulators with revolute joints are highly nonlinear. As a result, an even greater demand is placed on the dynamic response of the prime actuators since the actuating torques required for accurate tracking of a desired trajectory must contain a significant number of higher harmonics of the joint trajectory harmonics. In this paper, a systematic method is presented for optimal integration of active materials based actuators into the structure of robot manipulators for the purpose of minimizing the higher harmonic components of the required actuating torques. Through computer simulation, it is shown that with low harmonic joint trajectories and by minimizing the higher harmonic components of the actuating torques with properly sized and positioned smart actuators, robot manipulators can operate at higher speeds, with greater tracking precision and with minimal vibration and control problems.