In this paper, we consider the track-following control problem in the optical data storage systems in the presence of the eccentricity. The eccentricity results in the radial deviation of the objective lens so that it degrades the reliability of the data decoding system. To cope with the eccentricity, an adaptive disturbance compensation technique is newly proposed in the time domain based on a...

This paper presents an alternative approach for active vibration control for systems with periodic disturbances of time-varying fundamental frequency. The motivation for this approach is active control of engine-induced vibration in automotive vehicles, where the fundamental frequency, i.e., engine firing frequency, goes from approximately 7 Hz at idle (840 rpm) to approximately 50 Hz (6000 rpm...

The use of Disturbance Observer-based (DOB) control is widespread in stabilizing the electromagnetic field superconducting radio frequency cavities to facilitate beam acceleration particle accelerators. Repetitive disturbances such as loading and Lorentz force cavity detuning are compensated by DOB control, their suppression enhanced through incorporation a learning scheme into conventional dis...

We consider the stabilization for 1-D hyperbolic differential equations with boundary input including a nonlinear disturbance. The time varying extended state observer (ESO) is designed to estimate the disturbance. Based on the estimated disturbance, we obtain an explicit controller by applying the backstepping method. It is shown that the closed-loop system of the 1-D hyperbolic differential e...

*Correspondence: [email protected]; [email protected] 1School of Instrumentation Science and Opto-Electronics Engineering, Beihang University, Beijing, 100191, China 2School of Information and Control, Nanjing University of Information Science and Technology, Nanjing, 210044, China Abstract In this paper, a composite disturbance-observer-based control (DOBC) and H∞ control scheme is app...

To handle the state estimation of a nonlinear system perturbed by a scalar disturbance distributed by a known nonlinear vector, we incorporate a sliding mode term into a nonlinear observer to realise a robust nonlinear observer. By linking the observability of the unknown input to the output measurement, the so-called matching condition is avoided. The measurable output estimation error is the ...

The purpose of this work is to present an adaptive sliding mode Luenberger state observer with improved disturbance rejection capability and better tracking performance under dynamic conditions. The sliding hyperplane is altered by incorporating the estimated disturbance torque with the stator currents. In addition, the effects of parameter detuning on the speed convergence are observed and com...

The standard way to achieve offset-free tracking in MPC is to add the disturbance dynamics to the prediction model and then use an observer to estimate the real disturbance. Existing algorithms only consider piecewise constant signals, while in practice it is often desirable to have a wider choice of reference and disturbance dynamics, such as sinusoids and ramps. This work provides a generaliz...

This study proposed a novel robust sliding mode control strategy for the stabilized platform of rotary steering drilling system. Firstly, a Nonlinear Disturbance Observer (NDO) which can converge exponentially with suitable design parameters is used to observe the uncertain disturbance of stabilized platform under work condition. Subsequently, sliding mode controller is designed to guarantee th...