Abstract
Static force to an actuator is switched by a microcomputer in which displacement of an impacter is compared with on-off positions stored and decides on-off timing of the excitation. The switching causes self-excited impact vibration by rectangular pulsive force train. The paper presents estimation of drive condition for the steady-state motion by energy supplied dissipation per unity time, the power dissipation, for comparison of the motions having a different period. The optimum bipolar drive condition by the power estimation is available in the case that both the switch on position for the pull up force and the switch off position for the pull down force agree with impact position, in addition that the pull down force is acted in the moment of cut of the pull up force. In other words, the power is minimized by bang-bang drive. In the case of unipolar drive by the pull down force, there is not the practical condition, because the duration of force decreases to infinity and the force level increases to infinity. Hence it is reasonable that the force level is selected as high as possible and its corresponding duration of the pull down force is determined.
