In this paper, a grey sliding-mode controller is proposed to regulate the wheel slip, depending on the vehicle forward velocity. The proposed controller anticipates the upcoming values of wheel slip and takes the necessary action to keep the wheel slip at the desired value. The performance of the control algorithm as applied to a quarter vehicle is evaluated through simulations and experimental studies that include sudden changes in road conditions. It is observed that the proposed controller is capable of achieving faster convergence and better noise response than the conventional approaches. It is concluded that the use of grey system theory, which has certain prediction capabilities, can be a viable alternative approach when the conventional control methods cannot meet the desired performance specifications.

A Grey System Modeling Approach for Sliding-Mode Control of Antilock Braking System

A novel method for non-linear control of wheel slip in anti-lock braking systems

In this paper, the use of extended Kalman filter for the optimization of the parameters of type-2 fuzzy logic systems is proposed. The type-2 fuzzy logic system considered in this study benefits from a novel type-2 fuzzy membership function which has certain values on both ends of the support and the kernel, and uncertain values on other parts of the support. To have a comparison of the extended Kalman filter with other existing methods in the literature, particle swarm optimization and gradient descent-based methods are used. The proposed type-2 fuzzy neuro structure is tested on different noisy input-output data sets, and it is shown that extended Kalman filter has a better performance as compared to the gradient descent-based methods. Although the performance of the proposed method is comparable with the particle swarm optimization method, it is faster and more efficient than the particle swarm optimization method. Moreover, the simulation results show that the proposed novel type-2 fuzzy membership function with the extended Kalman filter has noise rejection property. Kalman filter is also used to train the parameters of type-2 fuzzy logic system in a feedback error learning scheme. Then, it is used to control a real-time laboratory setup ABS and satisfactory results are obtained.

Extended Kalman Filter Based Learning Algorithm for Type-2 Fuzzy Logic Systems and Its Experimental Evaluation

In this paper an integral backstepping sliding mode controller is proposed for controlling underactuated systems. A feedback control law is designed based on backstepping algorithm and a sliding surface is introduced in the final stage of the algorithm. The backstepping algorithm makes the controller immune to matched and mismatched uncertainties and the sliding mode control provides robustness. The proposed controller ensures asymptotic stability. The effectiveness of the proposed controller is compared against a coupled sliding mode controller for swing-up and stabilization of the Cart–Pendulum System. Simulation results show that the proposed integral backstepping sliding mode controller is able to reject both matched and mismatched uncertainties with a chattering free control law, while utilizing less control effort than the sliding mode controller.

Integral backstepping sliding mode control for underactuated systems: swing-up and stabilization of the Cart-Pendulum System.

Genetic fuzzy self-tuning PID controllers for antilock braking systems

Antilock brake system (ABS) has been designed to achieve maximum negative acceleration by preventing the wheels from locking. Research shows that the friction between road and tire is a nonlinear function of wheel slip. Therefore, maximum negative acceleration can be achieved by designing a suitable control system for wheel slip regulation at its optimum value. Since there is a lot of nonlinearity and uncertainty (uncertainty in mass and center of gravity of the vehicle and road condition) in vehicle dynamics, a robust control method should be used. In this research, a sliding mode controller for wheel slip control has been designed based on a two-axle vehicle model. Important considered parameters for vehicle dynamic include two separated brake torques for front and rear wheels as well as longitudinal weight transfer caused by the acceleration or deceleration. One of the common problems in sliding mode control is chattering phenomenon. In this paper, primary controller design has been improved using integral switching surface to reduce chattering effects. Simulation results show the success of integral switching surface in elimination of chattering side effects and by high performance of this controller. At the end, the performance of the designed controller has been compared with three of the prevalent papers results to determine the performance of sliding mode control integrated with integral switching surface.

Designing a sliding mode controller for slip control of antilock brake systems

Direct yaw moment control (DYC) is a recent active safety method introduced to control vehicle handling dynamics in non-linear regimes. The external yaw moment is considered as an important control input for DYC, which should be kept as low as possible. In the current paper, to achieve this aim, an optimal yaw rate tracking law is developed for DYC by the response prediction of a continuous non-linear vehicle dynamics model. A linear yaw rate model limited by tyre/road conditions is proposed as a desired model to be tracked by the controller. The derived control law is evaluated and its main features are discussed. The performed analysis gives an insight into the regulation of free parameters of the control law to make a compromise between tracking accuracy and control energy. The effectiveness of the designed controller is compared with a sliding mode controller, reported in literature, through simulations of various manoeuvres using a developed non-linear full vehicle dynamics model. The simulation resu...

An optimal approach to non-linear control of vehicle yaw dynamics:

For a direct yaw moment control (DYC) system, using an external yaw moment that is as low as possible for stabilizing the vehicle-handling dynamics in the non-linear regimes can be consider

Optimization-based non-linear yaw moment control law for stabilizing vehicle lateral dynamics

78  Abstract—In this paper, a nonlinear optimal control law based on a quadratic cost function is developed, and applied on a half-car model for the control of active suspension systems. Nonlinear model of half-car is constructed using the nonlinear dynamics of the electro hydraulic actuator and dynamic characteristics of the dampings and springs. The states of half car model are first estimated by Extended Kalman Filter (EKF) and then the estimated states predicted by Taylor series expansion and finally a control law is introduced by minimizing the local differences between the predicted and desired states. The derived control law has an analytical form which is easy to apply and also it is not required online numerical computations in optimization. Performance of the nonlinear optimal controller is compared to the existing passive suspension system and the proportional integral sliding mode controller. The obtained results demonstrate that use of the proposed nonlinear optimal control technique improves the tradeoff between ride quality and suspension travel compared to the passive suspension system and the proportional integral sliding mode method.

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A New Optimal Nonlinear Approach to Half Car Active Suspension Control

In this paper, we introduce a new adaptive controller design scheme for nonlinear telerobotic systems with varying time delays where the delays and their variation rates are unknown. The designed controller has the ability to synchronize the state behaviors of the local and the remote robots. In this paper, asymptotic stability in the presence of varying time delays is of interest. Using the proposed controller, asymptotic stability of the bilateral telerobotic system subject to any bounded yet unknown varying delay with a bounded yet unknown rate of change can be guaranteed. Besides the varying time delay, the proposed adaptive controller has the ability to adapt to the parameter variations in the local and the remote robots' dynamics. It is shown that position and velocity errors between the local and the remote manipulators converge to the zero asymptotically, thus ensuring teleoperation transparency. Experimental and simulation results with a pair of PHANToM haptic devices and a pair of planar manipulators under varying time delays in the communication channel demonstrate the effectiveness of the proposed scheme.

/pdf/adaptive-control-for-state-synchronization-of-nonlinear-3fentg8rb1.pdf

Ghasem Alizadeh

Papers

Designing a sliding mode controller for slip control of antilock brake systems

An optimal approach to non-linear control of vehicle yaw dynamics:

Optimization-based non-linear yaw moment control law for stabilizing vehicle lateral dynamics

A New Optimal Nonlinear Approach to Half Car Active Suspension Control

Adaptive Control for State Synchronization of Nonlinear Haptic Telerobotic Systems with Asymmetric Varying Time Delays