Mohammed Taleb

A novel adaptive-gain supertwisting sliding mode controller: Methodology and application

A novel super-twisting adaptive sliding mode control law is proposed for the control of an electropneumatic actuator. The key-point of the paper is to consider that the bounds of uncertainties and perturbations are not known. Then, the proposed control approach consists in using dynamically adapted control gains that ensure the establishment, in a finite time, of a real second order sliding mode. The important feature of the adaptation algorithm is in non-overestimating the values of the control gains. A formal proof of the finite time convergence of the closed-loop system is derived using the Lyapunov function technique. The efficiency of the controller is evaluated on an experimental set-up.

Adaptation of sliding modes

Adaptive sliding mode strategies of first and second sliding orders are developed for single-input single- output systems of the first and second relative degrees respectively. Since the only concrete known uncertainty bounds are assumed to be the upper bounds of logarithmic derivatives, no standard sliding- mode technique can solve the problem

Lyapunov design of adaptive super-twisting controller applied to a pneumatic actuator

Abstract A novel super-twisting adaptive sliding mode control law is derived using Lyapunov function technique. The both drift uncertain term and multiplicative perturbation are assumed to be bounded with unknown boundaries. The proposed approach consists in using dynamically adapted control gains that ensure the establishment, in a finite time, of a real second order sliding mode. The efficacy of the proposed super-twisting control algorithm is evaluated through its application to position control of an electropneumatic actuator.

Twisting-controller gain adaptation

Adaptation of twisting controller is performed in order to diminish the discontinuous control magnitude. The second-order real sliding mode is stably kept due to the instant multiplication of the gain by a chosen constant factor at the moments when the divergence is detected. Then the gain is gradually decreased. The resulting gain maxima are proved not to exceed the unknown equivalent control magnitude multiplied by a certain factor. Computer simulation confirms the theoretical results.

Third order sliding mode controller based on adaptive integral sliding mode concept: Experimental application to an electropneumatic actuator

This paper presents an adaptive third order sliding mode controller based on integral sliding mode concept. This new controller is designed for the position control of an electropneumatic actuator, on which bounded external perturbations with unknown magnitude are applied. The efficiency of the controller is experimentally evaluated.

Higher Order Sliding Mode Control Based on Adaptive First Order Sliding Mode Controller

Abstract This paper presents an adaptive higher order sliding mode controller based on first adaptive sliding mode control and an integral sliding variable. The idea is based on the definition of a nominal control which can stabilize a pure chain of integrators to zero in finite time. The novelty of the proposed approach is that uncertainties/perturbations effects are rejected by a first order sliding mode control tuned without any information about the bounds of the uncertainties. The efficiency of this controller is evaluated on an academic example with two kinds of nominal controls.

Twisting algorithm adaptation for control of electropneumatic actuators

The paper proposes a new adaptive version of the twisting algorithm, which is a traditional second order sliding mode controller. Due to dynamic adaptation of the gains, the controller design does not require complete information on the uncertainties/perturbations (bounds). It allows to decrease the gain magnitude and then the oscillations caused by a too large control magnitude: it improves the performance of the closed-loop system (accuracy). To show the feasibility of the approach, the methodology is applied to position control of an electropneumatic actuator.

Adaptive Second Order Sliding Mode Control: Application to Position and Force Control of Electro-Pneumatic Actuators

This paper presents an application of adaptive 2nd order sliding mode control. This control is based on twisting algorithm and ensures a finite time convergence to the sliding manifold σ = σ = 0, σ being the sliding variable and defined from the control objectives. The control solution required a limited information about the uncertainties and the disturbances acting on the system. This control strategy is applied to an electropneumatic set-up. This bench consists of two rod coupled pneumatic cylinders: one cylinder is controlled on position and perturbed by the second cylinder which is force-controlled. The efficacy of this strategy is evaluated through some simulations.Copyright