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The objective of the Integrated Chassis Controllers (ICC) is to combine multiple actuators and dynamics controllers to maximize the overall vehicle performance at all driving conditions. It is well known that there are two methods that can be used to develop an ICC. The first is a centralized method, where all the actuators are considered in one controller to ensure a harmonic integration between different actuators. The second method is called decentralized integration, where each actuator is considered in a separate controller and a low-level controller is used to coordinate the operation of the controllers. In this paper, the second method is used to develop a decentralized ICC using a novel controller coordinator based on Genetic Programming (GP). The GP is used to integrate torque vectoring and active rear steering controllers of an 8x8 combat vehicle. The controller is utilized to enhance the lateral stability of the vehicle in various driving conditions.

This paper investigates the impact of tread design on the tire-terrain interaction of two similar-sized truck tires with distinctly different tread designs running over various terrains and operating conditions using advanced computation techniques. The two truck tires used in the research are off-road tires sized 315/80R22.5 wide which were designed through Finite Element Analysis (FEA). The truck tire models were validated in static and dynamic domains using several simulation tests and measured data. The terrain includes a flooded surface and a snowed surface which were modelled using Smoothed-Particle Hydrodynamics (SPH) technique and calibrated using pressure-sinkage and direct shear tests. Both truck tire models were subjected to rolling resistance and cornering tests over the various flooded surface and snowed surface terrain conditions on the PAM-CRASH software.

Slip or relative rotation between the tire and rim is a significant concern for vehicle operation and wheel manufacturing since it leads to wheel imbalance and vibration as well as power losses. A slip situation typically occurs due to improper bead lubrication and mounting, irregularities in the bead seat, and extreme loading conditions with high torques and low tire pressures. Currently, there are relatively few published studies on the tire-rim interface, and they mainly focus on topics such as the mounting process, load transfer, and friction modelling. This leaves a gap to explore the measurement and variation of gross tire-rim slip under the dynamic conditions of a driven tire. In this paper, a previously developed and validated FEA truck tire model was modified to include a frictional contact surface between the tire and rim, and then the slip ratio between the tire and rim was measured under different operating conditions.

This paper investigates the tire-road interaction for tires equipped with two different solid rubber material definitions within a Finite Element Analysis virtual environment, ESI PAMCRASH. A Mixed Service Drive truck tire sized 315/80R22.5 is designed with two different solid rubber material definitions: a legacy hyperelastic solid Mooney-Rivlin material definition and an Ogden hyperelastic solid material definition. The popular Mooney-Rivlin is a material definition for solid rubber simulation that is not built with element elimination and is not easily applicable to thermal applications. The Ogden hyperelastic material definition for rubber simulations allows for element destruction. Therefore, it is of interest and more suited for designing a tire model with wear and thermal capabilities.

With the rise in demand, advanced steering control and electric vehicle technology are rapidly developing in modern times. Due to a controller's role as a backbone for the modern vehicle, its study has become increasingly crucial. This research proposes a novel 4th axle steering (4AS) feedforward controller that utilizes the first, second and fourth axle steering control for an 8x8 scaled electric combat vehicle. The vehicle is tested using the predefined path following. The novel 4AS controller is then compared to the Ackermann steering condition at different speeds. In the scaled vehicle used for this research, each wheel is independently driven by an in-wheel motor, while the steering is carried out by linear actuators. Individual eight-wheel steering control systems are designed and installed on the scaled vehicle to evaluate the driving performance from low speed to high speed. The 4AS steering method is implemented to improve the stability of the scaled vehicle at high speeds.