Zulkiffli Abd Kadir

Modelling, validation and roll moment rejection control of pneumatically actuated active roll control for improving vehicle lateral dynamics performance

This paper presents a detailed derivation of a full vehicle model and validation using an instrumented experimental vehicle. Two types of vehicle dynamics test are performed for the purpose of model validation namely step steer test and double lane change test. The results of model validation show that the behaviours of the model closely follow the behaviour of a real vehicle. An active roll control (ARC) suspension system is then developed on the validated full vehicle model to reduce unwanted vehicle motions during cornering manoeuvres. The proposed controller structure for the ARC system is PID control with roll moment rejection loop. The results of the study show that the proposed control structure is able to significantly improve the dynamics performance of the vehicle compared to the passive vehicle system. The additional roll moment rejection loop is able to further improve the performance of the PID controller for the ARC system.

Simulation and experimental evaluations on the performance of pneumatically actuated active roll control suspension system for improving vehicle lateral dynamics performance

This paper presents the derivation of a full vehicle model which consists of ride, handling and tyre subsystems to study vehicle dynamics behaviour in the lateral direction. The full vehicle model is then validated experimentally using an instrumented experimental vehicle based on steering wheel input from the driver. Three types of vehicle dynamics test were performed for model validation, namely step steer, slalom and double lane change tests. The validation results show that the behaviours of the model are similar to the real vehicle with acceptable error. An Active Roll Control (ARC) suspension system was developed using the validated full vehicle model to reduce unwanted vehicle motions during steering input manoeuvres such as body roll angle, body roll rate, vertical acceleration of the body and body heave. The proposed controller for the ARC system is a combination of Proportional-Integral-Derivative (PID) control with roll moment rejection loop. The results of the study show that the proposed control structure significantly improves the dynamics performance of the vehicle during step steer, slalom and double lane change manoeuvres compared with a passive vehicle system. The additional roll moment rejection loop is found to be able to further improve the performance of the PID ARC system. The effectiveness of the ARC system with the proposed control was also proven experimentally using the instrumented experimental vehicle.

Modeling, validation and firing-on-the-move control of armored vehicles using active front-wheel steering

It is a well-known fact that an armored vehicle will lose its directional stability when firing a large-caliber gun while moving. The instability is caused by the impulse force from firing, acting at the center of a weapons platform that produces a yaw moment at the center of gravity of the armored vehicle. In order to improve the stability, this paper introduces a firing-on-the-move technology for armored vehicles using an active front-wheel steering (AFS) system. The AFS system is proposed to maintain the directional stability of the armored vehicle by providing an electronically controlled correction to the steering mechanism. The steering correction is designed to reject the unwanted yaw motion and bring the vehicle back to its intended direction of travel after firing. The proposed control strategy of the AFS system in this study consists of yaw rate feedback with lateral force rejection control. The AFS system controller is developed on a validated 10-degrees-of-freedom armored vehicle. The results indicate that the developed control strategy can effectively maintain the directional stability, in terms of yaw and lateral motions, of the armored vehicle after firing. The superiority of the proposed AFS system controller is also evaluated by comparing its performance to an AFS system without lateral force rejection control as well as to a conventional armored vehicle without AFS.

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.

Active roll control suspension system for improving dynamics performance of passenger vehicle

This paper presents the roll moment rejection control of pneumatically actuated active roll control (ARC) suspension system for a passenger vehicle. The controller consists of the two controller loops namely inner loop controller to cancel out the unwanted weight transfer and outer loop controller to suppress both body vertical displacement and body roll angle using Fuzzy Logic Control. Two types of vehicle dynamics test are performed by simulation for the purposed control structure namely step steer test and double lane change test. The results of simulation show that the ARC system is able to significantly improve the dynamic performance of the vehicle compared with the passive system such as body roll angle, body roll rate, body vertical acceleration and body vertical displacement.

Pid Controller with Roll Moment Rejection for Pneumatically Actuated Active Roll Control (ARC) Suspension System

This chapter presents a successful implementation of PID controller for a pneumatically actuated active roll control suspension system in both simulation and experimental studies. For the simulation model, a full vehicle model which consists of ride, handling and tire subsystems to study vehicle dynamics behavior in lateral direction is derived. The full vehicle model is then validated experimentally using an instrumented experimental vehicle based on the driver input from the steering wheel. Two types of vehicle dynamics test are performed for the purpose of model validation namely step steer test and double lane change test. The results of model validation show that the behaviors of the model closely follow the behavior of a real vehicle with acceptable error. An active roll control (ARC) suspension system is then developed on the validated full vehicle model to reduce unwanted vehicle motions during cornering maneuvers such as body roll angle, body roll rate, vertical acceleration of the body and body heave. The proposed controller structure for the ARC system is PID control with roll moment rejection loop. The ARC system is then implemented on an instrumented experimental vehicle in which four units of pneumatic actuators are installed in parallel arrangement with the passive suspension system. The 1

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.

Design and characterisation of external orifice semi-active suspension system for armoured vehicle application

The objective of this paper is to investigate the force-velocity characteristics of a new design of external orifice semi-active suspension system (EOSASS). EOSASS is a class of semi-active system where the orifice area is controlled electronically using an electric motor. The idea of EOSASS is to modify the internal fixed orifice of the existing passive damper into externally controllable using hydraulic unit. The behaviour of the EOSASS is tested in terms of its force-velocity and force-displacement characteristics using Instron 8801 Servohydraulic fatigue testing system and WaveMatrix dynamic testing software. The ratio of the orifice opening area for the compression and extension on the hydraulic unit is varied in order to study the hysteresis behaviour of the damper. From the experimental results, the relationship between the damping force and the ratio of orifice opening during extension and compression are obtained. It was verified that decreasing the ratio of orifice opening will produce higher damping force in both compression and extension stages.

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.

Modeling, Validation, and Control of Electronically Actuated Pitman Arm Steering for Armored Vehicle

In this study, 2 DOF mathematical models of Pitman arm steering system are derived using Newton’s law of motion and modeled in MATLAB/SIMULINK software. The developed steering model is included with a DC motor model which is directly attached to the steering column. The Pitman arm steering model is then validated with actual Pitman arm steering test rig using various lateral inputs such as double lane change, step steer, and slalom test. Meanwhile, a position tracking control method has been used in order to evaluate the effectiveness of the validated model to be implemented in active safety system of a heavy vehicle. The similar method has been used to test the actual Pitman arm steering mechanism using hardware-in-the-loop simulation (HILS) technique. Additional friction compensation is added in the HILS technique in order to minimize the frictional effects that occur in the mechanical configuration of the DC motor and Pitman arm steering. The performance of the electronically actuated Pitman arm steering system can be used to develop a firing-on-the-move actuator (FOMA) for an armored vehicle. The FOMA can be used as an active safety system to reject unwanted yaw motion due to the firing force.