Structural design, analysis, and performance evaluation of a new semi-direct drive robot arm: theory and experiment

This paper reports the mechanical design, structural analysis, and experimental verification of a new high-performance semi-direct drive robot arm. A design-optimization methodology employing finite element analysis (FEA) is reviewed, and a resulting arm design is reported. FEA simulations of the final design predict high structural vibration frequencies throughout the arms workspace. Extensive structural vibration experiments with the completed manipulator confirm the predicted structural vibration characteristics throughout the arm's workspace. Position-tracking experiments show that the manipulator accurately tracks fast time-varying reference trajectories-peak tip velocities greater than 6 m/s and peak tip accelerations greater than 7 g.