Proposal of Electro Mechanical Resonance for Linear Oscillatory Actuator

Linear resonant actuators have been used in a wide range of applications because they utilize mechanical resonance and operate at high efficiency. However, the amplitude of LRAs severely decreases when external loads are applied. To solve this problem, we applied PID control to an LRA and the mover amplitude remained constant against an external load. When a large external load is applied with the target voltage of PID control high, however, input power reaches maximum and the amplitude does not follow the target value. As a solution, it is effective to utilize electrical resonance and generate large current. In this paper, we propose a driving theory to generate electrical resonance. The effectiveness of the proposed method is verified through dynamic analysis using 2-D finite element method.