Voice Coil Motor

In this paper, we extend the concept of the contrast sensitivity function—used to evaluate video projectors—to the evaluation of haptic devices. We propose using human observers to determine if vibrations rendered using a given haptic device are accompanied by artifacts detectable to humans. This determination produces a performance measure that carries particular relevance to applications involving texture rendering. For cases

Pneumatic vibration isolation tables are employed in the field of semiconductor manufacturing and precision measurement. There are three main flow disturbances such as flow variation, non-uniformed flow and random flow drops of the supplied air that cause the fluctuations of the isolation table. Multi-connection air regulators are often used for the control of flow variation of the supplied air. However, the multi-connection air regulators lead to the pressure loss of the compressed air. Previously, we used two feedforward control methods for the control of flow disturbances. Both methods utilized pressure sensor to measure the supplied air pressure and provide feedforward control signal to the actuators. One method used air spring and the other used voice coil motor (VCM) as the actuators. The current study proposes a flow meter instead of a pressure sensor to measure the supplied air flow at the output of the air compressor and send feedforward signal to the actuator, VCM, to cont...

In this paper we discuss the controller design of a PZT-actuated suspension dual-stage servo system in hard disk drives. The proposed control structure includes an active vibration damping control loop and a track-following control loop. The vibration damping control loop, which runs at a faster rate than the track-following control loop, utilizes a PZT element on a PZT-actuated suspension as a vibration sensor to damp the resonance modes of the voice coil motor (VCM) and the PZT actuator. The vibration damping controller is designed using Kalman filter based state feedback control techniques. A simple dual-stage track-following controller is designed, based on the damped actuator model, using the sensitivity function decoupling design method. Simulation and experimental results are presented to demonstrate the benefits of this control scheme in expanding servo control bandwidth and suppressing airflow excited structural vibrations.

This paper presents the design and control of a rotary dual-stage actuator (DSA) system, which consists of a voice coil motor (VCM) and a piezoelectric (PZT) microactuator. The performance of the mechanical design is analyzed using a finite element method (FEM) software, whose simulation results are validated experimentally. A nonlinear tracking control is applied to the developed DSA platform for