Vimal Rau Aparow

Modelling and PID control of antilock braking system with wheel slip reduction to improve braking performance

This paper presents the development of a PID controller for an Antilock Braking System (ABS) using vehicle longitudinal model. A Five Degree of Freedom (5-DOF) vehicle longitudinal dynamic model was derived and integrated with an analytical tyre dynamics, the Magic Tyre model. Several transient handling tests are performed such as sudden acceleration and sudden braking test to validate the vehicle model. The model is used as a plant to develop an antilock braking system to control longitudinal slip and reduce the stopping distance. A hydraulic brake model was developed as the brake actuator to produce brake torque. A conventional PID controller has been implemented to deal with the strong nonlinearity in the design of ABS controller. The proposed ABS control structure is shown able to significantly reduce stopping distance and control the longitudinal slip during heavy braking.

Model-in-the-loop simulation of gap and torque tracking control using electronic wedge brake actuator

This paper presents gap and torque tracking controls of a new braking system for Brake-by-Wire (BBW) using a wedging mechanism. A validation technique known as Model-in-the-Loop Simulation (MILS) is proposed to evaluate the effectiveness of EWB actuator and model. MILS is divided into two types of techniques, which are Hardware-in-the-Loop Simulation (HILS) using real EWB actuator and Software-in-the-Loop Simulation (SILS) using Gaussian cumulative distribution technique. A brake test rig is developed for HILS using EWB actuator, Electronic Control Unit, National Instrument board, xPC Host and Target PC. Meanwhile, mathematical equations are developed for SILS using Matlab Simulink. Both techniques are used to evaluate the performance of EWB actuator and EWBs mathematical model in controlling the gap and torque using various inputs. The results show that the responses from the actuator and EWB model closely followed the desired trajectories, indicating that EWB is capable to be used for vehicle active braking.

Development of Antilock Braking System Based on Various Intelligent Control System

This paper presents about the development of an Antilock Braking System (ABS) using quarter vehicle model and control the ABS using different type of controllers. Antilock braking system (ABS) is an important part in vehicle system to produce additional safety for drivers. In general, Antilock braking systems have been developed to reduce tendency for wheel lock and improve vehicle control during sudden braking especially on slippery road surfaces. In this paper, a variable structure controller has been designed to deal with the strong nonlinearity in the design of ABS controller. The controllers such as PID used as the inner loop controller and Fuzzy Logic as outer loop controller to develop as ABS model to control the stopping distance and longitudinal slip of the wheel.

Modelling and trajectory following of an armoured vehicle

In this study, a trajectory following strategy consists of two feedback loops is employed on an armoured vehicle to follow a pre-defined trajectory using PID controllers. A 7 Degree-of-Freedoms (DOF) mathematical model is used to model the armoured vehicle which considers full vehicle interactions including tire model, powertrain model, slips and vertical load distribution model. Next, parametric study for the PID parameters was carried out. To tune the PID parameters, two methods are used namely try-and-error based on the parametric study and also using Particle Swarm Optimisation (PSO) algorithm. Lastly, controller responses were evaluated and compared in terms of its performance in following the trajectory. It was proven that PSO algorithm manage to tune and optimise the PID controller parameters for the trajectory following control.

Adaptive modified Stanley controller with fuzzy supervisory system for trajectory tracking of an autonomous armoured vehicle

Abstract In developing path tracking controller for autonomous vehicles, a properly tuned controller will work well for a certain range of driving conditions but may need to be re-tuned for others. This study presents the development of an adaptive controller with fuzzy supervisory system for trajectory tracking control of an autonomous armoured vehicle. A knowledge database is built using Particle Swarm Optimisation which is the mainframe of the Fuzzy supervisory system in adapting to various trajectories and speed. The proposed controller is simulated on a nonlinear vehicle model, and experimental results for the controller are presented to evaluate the proposed controller.

Identification of an optimum control algorithm to reject unwanted yaw effect on wheeled armored vehicle due to the recoil force

This article presents an active safety system for a wheeled armored vehicle to encounter the effect of the firing force. The firing force which acts as an external disturbance causes unwanted yaw moment occurred at the center of gravity of the wheeled armored vehicle. This effect causes the wheeled armored vehicle lose its handling stability and the traveling path after the firing condition. In order to overcome the stability problem, a Firing-On-the-Move assisted by an Active Front Wheel Steering system is proposed in this study. This system is developed based on two established systems, namely, Firing-On-the-Move and Active Front Wheel Steering systems. The proposed system is designed to improve the handling and directional stability performances of the armored vehicle while fires in dynamic condition. Four types of control strategies are designed and investigated in this study to identify the most optimum control strategy as the Firing-On-the-Move assisted by an Active Front Wheel Steering system using optimization tool, genetic algorithm. The control strategies for the Firing-On-the-Move assisted by an Active Front Wheel Steering are evaluated using various types of vehicle speeds and firing angle in order to obtain an appropriate control structure as the Firing-On-the-Move assisted by an Active Front Wheel Steering system for the wheeled armored vehicle.

Active Front Wheel Steering System of 4×4 armored vehicle: Rejection of unwanted firing disturbance

Effect of firing force from the gun turret causes external disturbance to an armored vehicle. This disturbance has effected the dynamic performance of the armored vehicle while firing in a moving situation. Therefore, an active safety system is required in order to minimize the effect of firing disturbance to improve the dynamic performance and directional stability of the armored vehicle. In this paper, Active Front Wheel Steering System (AFWS) has been developed as an active safety system for the armored vehicle. An armored vehicle model using Pitman Arm Steering and DC motor model has been used to study the performance of the armored vehicle model using AFWS. In order to enhance the performance of AFWS, additional embodiment known as Estimated Yaw and Lateral disturbance Rejection (EsYLaR) has been included in the control strategy. The performance of the armored vehicle is evaluated in term of yaw rate, yaw angle, lateral acceleration and lateral displacement.

Simulation and experimental investigation of vehicle braking system employing a fixed caliper based electronic wedge brake

This paper presents an investigation into the performance of a fixed caliper based electronic wedge brake (FIXEWB) in a vehicle braking system. Two techniques were used as assessment methods, which are simulation via MATLAB Simulink software and experimental study through hardware-in-the-loop-simulation (HILS). In the simulation study, the vehicle braking system was simulated by using a validated quarter vehicle traction model with a validated FIXEWB model as the brake actuator. A proportional–integral–derivative controller was utilized as the brake torque control, whereas proportional–integral and proportional controllers were used as the position and speed control of the actuator, respectively. To study the effectiveness of the FIXEWB, the response of the vehicle using the FIXEWB is compared with the responses of a vehicle using a conventional hydraulic brake. A dynamic test, namely braking in the sudden braking at constant speeds of 40 and 60 km/h was then used as the testing method. The simulation results show that the usage of the FIXEWB with an appropriate control strategy produces similar behavior to that of a hydraulic brake in terms of the produced desired braking torque but with faster time response. To study the performance of the FIXEWB when implemented on a real vehicle, an experimental rig using HILS was designed and the results are analyzed using the same dynamic tests. The performance areas evaluated are vehicle body speed, wheel speed, tire longitudinal slip, and the stopping distance experienced by the vehicle. The outcomes from this study can be considered in the design optimization of an antilock braking system control in a real car in the future.

Modelling and optimisation of active front wheel steering system control for armoured vehicle for firing disturbance rejection

While firing on the move, the handling performance of an armoured vehicle is affected, thus causing it to lose its directional stability. This is due to an impulse force generated at the centre of the gun turret, which can produce an unwanted yaw moment at the centre of gravity of the armoured vehicle. In order to reject the unwanted yaw moment, a new hybrid control strategy known as Neural-PI controller had been introduced by combining neural network system and conventional PI controller. This paper developed 14 DOF of armoured vehicle and 2 DOF of Pitman arm steering system. Other than that, determination of the most suitable activation function to be implemented in the Neural-PI controller has been carried out and optimised by using the Genetic Algorithm (GA) method. The performance of the controller was evaluated by comparing the conventional PI controller with the Neural-PI controller implemented with different activation functions.

Development of estimated disturbance rejection feedback for an armoured vehicle using active front wheel steering

An unwanted yaw motion occurred at the centre of gravity (CG) of the wheeled armoured vehicle caused by the impulse force generated during gun turret firing. The recoil force from the gun fire tends to create instability conditions for the armoured vehicle during firing condition and affects the dynamic performance of armoured vehicle in lateral direction. In this paper, an active safety system, active front wheel steering (AFWS) system using estimated disturbance rejection feedback (EDRF) embodiment is proposed to reject the unwanted yaw disturbance and stabilise the armoured vehicle. Besides, the proposed control strategy is also used to re-position the armoured vehicle back to its initial position. Therefore, a summation moment reference input is used to counter back the unwanted firing moment occurred due to gun firing impulse at CG of the armoured vehicle. The armoured vehicle is evaluated via simulation analysis in term of yaw rate, yaw angle, vehicle sideslip angle, lateral acceleration and lateral displacement. Significant improvements up to 75% have been achieved by using the proposed control strategy of AFWS system to reject the external disturbance due to the firing force.