Complete Adaptive Control Research Articles

Adaptive Pneumatic Control With Spool Deadband Compensation

AbstractThis paper presents a novel approach to both adaptive deadband compensation and complete adaptive pneumatic control for a pneumatic servo control system driven by spool-type pneumatic proportional directional control valves. The controller is capable of either combined position and compliance control or combined force and compliance control. The novel adaptive approach includes control valve deadband compensation and adaptation for load variations and system mechanical properties. The control valve deadband compensation uses adjustable deadband lengths that are adapted to improve force tracking performance. The learned deadband model is then used in the complete adaptive controller, which includes adaptation for system mass, damping, and external load. The complete controller demonstrated accurate and stable force and position control for the tracking of sine, square, and sawtooth waveforms from 1 to 5 Hz.

A DSP-based adaptive controller for a smooth positioning system

The implementation of a self-tuning regulator for the positioning of a direct-drive servomotor is described. The servo motor is a permanent magnet DC motor in which no speed reducer is used. The auto-tuning regulator consists of two major loops. The inner loop contains a feedback (PD or PID) regulator with additional feedforward terms. The parameters of the feedforward compensation are adjusted by the outer loop, which contains an online parameter estimator. The estimator is based on a recursive least-squares equation, and the estimated parameters are the load inertia and viscous friction. This self-tuning regulator has been simulated with PC.MATLAB, and the results demonstrate the high performance of the scheme. Experimental results obtained with a small DC motor (Electrocraft E-576) are presented, and these results show good agreement with the digital simulation results. There are two innovative aspects to this work. First, parameter estimation is used to adapt the feedforward compensation terms instead of the gains of the feedback controller, as usually is the case in conventional indirect self-tuning regulators. Secondly, the complete adaptive controller has been implemented using a single-chip digital signal processor (DSP), which results in the reduction of system hardware and cost.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>