Study on motion design for service robot based on standard human motion

Abstract

This paper found out the standard human motion which is exemplar motion for letting robot's motion approximate to human motion, and evaluated the human impression to the robot motion. The problems in case of finding out the standard human motion is how to specify one motion from different motions caused by individual physical characteristics and peculiarities. We have solved above problem by following method. First, the fundamental component was extracted from individual time series motion data by using Desecrate Fourier Transform, in order to remove walking cycle and noises and to easily map a motion to the phase plane. Next, the extracted individual fundamental components were plotted on the phase plane. Afterwards, individual patterns on the phase plane were fitted to the one ellipse by using least-squares method. And we regarded this ellipse as the standard human motion. This ellipse trajectory integrates motions even if different motion in time domain, and can absorb different motion cycle and amplitude caused by individual physical characteristics and peculiarities. Last, this ellipse trajectory was expressed as the time series functions by inverse mapping from phase to time domain, and they were implemented to the robot to replay the standard human motion in the simulation. Finally, in order to discuss the human impression from replayed standard human motion, the evaluation experiment using Semantic Differential (SD) Method was conducted. From the experimental results, the proposed motion design can let the robot motion approximate to the human motion, because the standard human motion is the fundamental motion among individuals and gives positive impression to users.