High efficiency driving of vibration propulsion mechanism by decentralized control

(Improvement of efficiency by optimization of each excitation force)

Abstract

This research concerns high efficiency propulsion method of multi-articulated robot by decentralized control using local feedback control. Recently, various robots, which are useful when disasters happened, have been studied. The high efficiency driving of these robots is required, because there are limits to an energy for robot propulsion at a time of disaster. To meet this requirement, the driving method using resonance point was proposed. On the other hand, natural frequencies of propulsion robot are varying in synchronization with the change of external environment. In this paper, the new driving method of propulsion robot using nonlinear control, which drives at the resonance point automatically, is proposed. Especially, investigation of the proposed method for large degree of freedom robot is done. Firstly, optimal excitation force of vibration propulsion mechanism is shown. The excitation force signal, which is realized the highest efficiency driving, is clarified by the driving experiment using various excitation force by centralized control. Secondly, the design method of new controller for decentralized control is introduced. The excitation force waveform of conventional control is square wave because of saturation element to limit the amplitude of excitation force. The new controller has the nonlinear damping element in place of saturation element. Finally, it is confirmed that the decentralized control using new controller can realizes the highest efficiency driving. The driving efficiency of the propulsion mechanism improved because of the optimization of the excitation force waveform.