This paper addresses an approximation-based anti-windup (AW) control strategy for suppressing the windup effect caused by actuator saturation nonlinearity in proportional–integral–derivative (PID) controlled systems. The effect of actuator constraint is firstly regarded as a disturbance imported to the PID controller. The external disturbance can then be modeled by a linear differential equatio...

This chapter demonstrates the use of anti-windup compensation in the control loop of a micro-actuator which is nominally controlled by a linear, discrete robust controller. The micro-actuator is part of a hard disk drive dual-stage servo-control system for positioning of the read/write head. The actuator inputs are constrained to retain the micro-actuator’s displacement range of less than 0.4 μ...

In this paper, the problem of adaptive tracking control is addressed for a class of nonlinear systems with parametric uncertainty, unknown actuator nonlinearity and disturbance. Two type of actuator nonlinearities, that is, backlash-like hysteresis and symmetric deadzone, are considered simultaneously. Without constructing the inverse function of actuator nonlinearity, unified control framework...

We present the design of a modular tactile sensor and actuator system for observing human demonstrations of contact tasks. The system consists of three interchangeable parts: an intrinsic tactile sensor for measuring net force/ torque, an extrinsic tactile sensor for measuring contact distributions , and a tactile actuator for displaying tactile distributions. The novel components are the extri...

This letter describes a method to analyze electromechanical stability of dielectric elastomer actuators. We write the free energy of an actuator using stretches and nominal electric displacement as generalized coordinates, and pre-stresses and voltage as control parameters. When the Hessian of the free-energy function ceases to be positive-definite, the actuator thins down drastically, often re...

In this paper a new soft actuator based on dielectric elastomer is proposed. The actuator, called ANTagonistically-driven Linear Actuator(ANTLA) has the musclelike characteristics capable of performing the motions such as forward/backward/controllable compliance. Due to its simplicity of configuration and ease of fabrication, it has the advantages to be scale– independently implemented in meso–...

The development of steerable guide wire or catheter designs has been strongly limited by the lack of enabling actuator technologies. This paper presents the properties of an electrostrive actuator technology for steerable actuation. By carefully tailoring material properties and the actuator design, which can be integrated in devices, this technology should realistically make it possible to obt...

There is often freedom in choosing the location of actuators on systems governed by partial differential equations. The actuator locations should be selected in order to optimize the performance criterion of interest. The main focus of this thesis is to consider H∞ performance with state-feedback. That is, both the controller and the actuator locations are chosen to minimize the effect of distu...

A vision-based approach to the motion control of pneumatic group actuators is presented. Sensing of plate locations consisting of the pneumatic group actuator is essential to cope with the variation of elastic tubes of the actuator. Plate locations are measured by a vision system and the motion of the actuator is controlled using a roughly identified relationship between air pressure imposed on...

-Authors propose the spherical electromagnetic actuator that applied Surface Motor. The feature of this actuator is the ability to arrange the magnetic poles uniformly by distributing the stator's magnetic poles in triangular lattice. In this paper, we report that the fundamental structure of this actuator and secondary side permanent magnets arrangement, and we measure the thrust force charact...