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This article describes the current state of the art in tire/suspension system misuse simulation, with particular attention to finite element tire modeling for severe impact situations. One such finite element tire model, developed in the PAMCRASH environment, is described and it's static performance discussed in relation to experimentally obtained data.

This paper details a non-linear hysteretic physical shock absorber model, and the processes utilised to identify the constituent parameters. In the current paper the model parameters are extracted from experimental data for the ‘sport’ setting of a prototype front shock absorber for a vehicle in the luxury class. The model is validated by comparing simulated results to experimental data for a test damper, for three discrete frequencies of sinusoidal excitation of 1,3 and 12 Hz. Finally the shock absorber model is included in a quarter car vehicle ride model and output characteristics are compared to those obtained with classical damper representations.

This paper presents a method of control for a 6×6 series-configured Hybrid Electric Off-road Vehicle (HEOV). The vehicle concerned is an eight-tonne logistics support vehicle which utilizes Hub Mounted Electric Drives (HMED) at each of its six wheel stations. This set-up allows Individual Wheel Control (IWC) to be implemented to improve vehicle handling and mobility. Direct Yaw-moment Control (DYC) is a method of regulating individual wheel torque to control vehicle yaw motion, providing greater stability in cornering. When combined with both a Traction Control System (TCS) and an Anti-lock Braking System (ABS) the tire/road interaction is fully controlled, leading to improved control over vehicle dynamics, whilst also improving vehicle safety.

Many of today's modern vehicles are ‘smart’ enough to sense their environments and make decisions that influence things such as handling, stability, safety and comfort. As of today, these systems are functioning in a standalone manner. Research shows the benefits of integration of these systems. This paper presents the development of an integrated control system amongst active front steering, active suspension, brake-based electronic stability control and variable torque distribution system. The simulation results show that this integration strategy enhances the vehicle handling stability in terms of reduction in vehicle yaw rate and side-slip angle that would not be attained in standalone manner.

Many active control systems are developed as safety systems for passenger vehicles. These control systems usually focus on improving vehicle stability and safety while ignoring the effects on the vehicle driveability. In the motorsport environment, increased stability is desirable but not if the driveability of the vehicle is heavily compromised. In this work, active suspension and active drivelines are examined to improve vehicle dynamics and enhance driveability while maintaining stability. The active control systems are developed as separate driveability and stability controls and tested individually then integrated to create a multi-objective control system to improve both driveability and stability. The controllers are tested with standard vehicle manoeuvres.

Most active control systems developed for passenger vehicles are developed as safety systems. These control systems usually focus on improving vehicle stability and safety while ignoring the effects on the vehicle driveability. While stability is the primary concern of these control systems the driveability of the vehicle is also an important consideration. An example of compromised driveability in a stability control system is brake based active yaw control. Brake based systems are very effective at stability control but can have a negative impact on the longitudinal dynamics of a vehicle. The objective of the vehicle control systems developed for the future will be to preserve vehicle driveability while ensuring the stability of the vehicle. In this work, active suspension and active drivelines are developed as stability control systems that have a minimal impact on the driveability of the vehicle.

High mobility combat support vehicles are used over the most demanding types of terrain. Key to their sucess is their off-road performance, particularly with respect to their ability to supply front line forces. Several factors limit their off-road performance including the driver's ability to endure the ride. Improving the ride through the use of intelligent suspension systems enables the vehicle to travel quicker over certain types of terrain. Previous research has identified semi-active suspension systems to have considerable potential for improving the performance of CSVs. This paper describes the development of a practical semi-active suspension for use on the DERA 6x6 demonstrator, fig 1. The modelling presented in this paper shows that this technology reduces the accelerations experienced by the driver by typically 15%. This improvement enables the driver to use increased vehicle speeds whilst maintaining the same level of discomfort.

It is often quoted that to be able to make a race car handle ‘properly’ by tuning the handling balance, the chassis should have a torsional stiffness of ‘X times the suspension stiffness’ or ‘X times the difference between front and rear suspension stiffness’ [1]. This paper looks at the fundamental issues surrounding chassis stiffness. It discusses why a chassis should be stiff, what increasing the chassis stiffness does to the race engineer's ability to change the handling balance of the car and how much chassis stiffness is required. All the arguments are backed up with a detailed quasi static analysis of the problem. Furthermore, a dynamic analysis of the vehicle's handling using ADAMS Car and ADAMS Flex is performed to verify the effect of chassis stiffness on a race car's handling balance through the simulation of steady state handling manoeuvres.