Dual-stage actuator design for hard disk drives via composite nonlinear feedback control is presented, which consists of a primary actuator, the voice coil motor and a secondary actuator, the suspension piezoelectric microactuator. The first is effective in both track seeking and following stages to produce fast rising time and low overshoot and the latter works in track following stage only to...

As tape recording density increases, high-frequency track following capability of the tape head actuator becomes more important. This paper details the mechanical design and experimental analysis of a dual state actuator tape head. The dual stage actuator design combines a traditional voice coil motor for low frequency track following with a piezoelectric actuator for high-frequency track follo...

Abstract To improve positioning accuracy in a head-positioning control system for hard disk drives, we have developed a triple-stage-actuator system on a spin-stand tester. In this system, the first stage is a VCM actuator for moving a head-stack assembly, the second stage is a PZT actuator for moving a suspension, and the third stage is a thermal actuator for moving read/write elements. The fr...

A new design for a multi-layer dielectric elastomer actuator, reinforced with periodic stiffeners is presented. The resulting actuator enables complex out-ofplane motion without the need of the elastomer membrane prestretch. An in situ optical imaging system is used to capture the complex deformation pattern and track the non-planar displacement and curvature under the applied voltage. The role...

A new design for a multi-layer dielectric elastomer actuator, reinforced with periodic stiffeners is presented. The resulting actuator enables complex out-ofplane motion without the need of the elastomer membrane prestretch. An in situ optical imaging system is used to capture the complex deformation pattern and track the non-planar displacement and curvature under the applied voltage. The role...

This paper presents a “Fingerprint Method” for modeling and subsequently characterizing stochastically controlled actuator arrays. The actuator arrays are built from small actuator cells with structural elasticity. These cells are controlled using a bistable stochastic process wherein all cells are given a common input probability (control) value which they use to determine whether to actuate o...

This chapter surveys the existing representative work in both sensor-actuator and actuator-actuator coordination. Sensor-actuator coordination deals with establishing data paths between sensors and actuators, and can be used for sensor deployment. Actuatoractuator coordination includes robot coordination for sensor placement, dynamic task allocation, selecting best robot to respond to reported ...

this paper presents a new observer design methodology for a time varying actuator fault estimation. a new linear matrix inequality (lmi) design algorithm is developed to tackle the limitations (e.g. equality constraint and robustness problems) of the well known so called fast adaptive fault estimation observer (fafe). the fafe is capable of estimating a wide range of time-varying actuator fault...

A robust control allocation scheme is developed for rigid spacecraft attitude stabilization in the presence of actuator partial loss fault, actuator failure, and actuator misalignment. First, a neural network fault detection scheme is proposed, Second, an adaptive attitude tracking strategy is employed which can realize fault tolerance control under the actuator partial loss and actuator failur...

This paper presents the analytical and experimental results on optimal placement of piezoceramic actuators for shape control of beam structures. The objective is to determine the optimum piezoceramic actuator locations and voltages to minimize the error between the desired shape and the achieved shape. The analytical model for predicting beam deformation due to a piezoelectric actuator is based...