Levitation energy of piezoelectric actuator using a levitation mechanism

Abstract

In this research, we focused on the energy consumed in the levitation mechanism used in an inchworm-type microactuator when the mechanism is levitated. We use a power meter for the measurement of the energy required for levitation. We estimate the levitation height by comparing the levitation height measured by a displacement sensor and the power consumption measured by a power meter. The levitation height measured with the displacement sensor shows the similar trend obtained with the power used in the levitation mechanism. We are studying a piezoelectric actuator used in a levitation mechanism. The levitation mechanism levitates using a squeeze effect caused by the vertical vibration of the piezoelectric element. Frictional force control is realized by using levitation mechanisms, and the microactuator moves by the principle of inchworm. We usually measure the displacement of the levitation mechanisms by the use of a displacement sensor. However, the measurement of the vertical direction is difficult because there are a number of limitations. Therefore, a measurement method without displacement sensors in the vertical direction is required. The estimation method proposed in this paper can extend the working range of the microactuators. The energy consumed in the microactuator includes the information of the actuator. We measure the energy and the state simultaneously, and levitation height used for levitation is estimated. The measured and estimated levitation height as a function of the operation frequency is also discussed.