Impact of the trajectory generation strategy on the driveline efficiency of a multi-axial robot

This paper investigates how the parameterization of the target trajectories impacts the weighting of transient and steady state energy losses in different components of a multi-axial robot and proposes ways of minimizing them in order to improve the overall driveline efficiency. As application case, a three-axial badminton robot is used. For the purpose of predicting the energy flow and the losses in the different parts of the system, a multi-domain simulation model of the robot is built and verified using measurement data gained on an experimental set-up. A Proximate Time-Optimal Servo-mechanism (PTOS) is used to generate the variable reference trajectories for the position controller. Sensitivity analysis is performed based on the PTOS parameters to identify the trends in efficiency and reveals that a reduction of energy losses over 150 % is achievable with only a performance degradation of 18 %.