Integrated Control of Vehicle Running Properties 2002-01-2216
The field of Vehicle Dynamics as the theory of a vehicle in motion is to study the vehicle's properties (vehicle running abilities) in the interaction of the vehicle and it's surroundings. This interaction itself appears through forces acting on a vehicle. To control these forces leads to control the properties of a vehicle in motion such as tractive and velocity properties, fuel consumption, turnability, ride stability and others.
This paper proposes a unique and novel theory of a vehicle in motion. This theory allows parallel control of the forces acting on a vehicle, which leads to considerable improvement of the vehicle's running abilities. This paper presents the interrelation between the criteria of vehicle running abilities and output characteristics of vehicle systems, which control the vehicle forces.
To optimize a vehicle's running abilities require optimization of the combinations of forces acting on a vehicle. To provide optimum control of these forces, a methodical investigation of force combinations is proposed to be implemented for the sub-system of wheel patch - powertrain, and for the sub-system of wheel patch - suspension system - steering system - vehicle body.
To illustrate the process of defining the optimum combination of forces acting on a vehicle in motion, a multiple criteria optimization problem of the wheel driving forces and, accordingly, output characteristics of wheel drive systems is being considered in this paper. Mathematically, the problem is based on the parallel controlling of tractive and velocity properties, fuel consumption performance, turnability, and ride stability of a vehicle. The problem is then reduced to a single criterion optimization with limitations of the rest of criteria and limitations of optimized parameters.
The development reported in the paper includes an application of the theory to a 12-wheeled highway truck. A mathematical model for studying the truck's running abilities is given based on the inverse dynamics problem. Optimal combinations of the wheel driving forces and logical control algorithms are presented to operate Traction Control and Anti Slip Differential Systems.