A control strategy for vehicle trajectory tracking using multibody models

The development of a virtual driver for a vehicle running in a given track constitutes an important application of vehicle dynamics. For this work a multibody based methodology for the design of a vehicle virtual driver is proposed. A simplified control model for the vehicle, which makes use of extended bicycle model, is implemented. The outcome of the controller based on the bicycle model is used to control a detailed multibody model of the real vehicle, including all suspension elements and tire/road forces, which provide the observed motion. The only variables that the control acts upon are the steering wheel angle and vehicle wheels' torques, which represent the traction and braking. The reference trajectory that has to be followed by the vehicle is defined by using a spline curve that represents its geometry. This description of the trajectory may be as complex as required by any particular application. The control model is implemented in the MATLAB environment while for the vehicle multibody model a stand alone multibody computer code is used. These two computational environments are interfaced using the available MATLAB communication functions. The virtual driver model is finally demonstrated for a sports vehicle that runs in prescribed track and the simulation results are discussed in face of the methods used.