STEERING CONTROL PROBLEM FORMULATION OF LOW-SPEED TRICYCLE-MODEL VEHICLES

This paper addresses the steering control problem formulation for path following in the plane motion of a class of low-speed ground vehicle that can be modelled as a tricycle. After a short discussion about the error correction mechanism, the equations of motion are obtained based on the system kinematics. These equations govern the characteristics of the control system of the steering action in terms of the two measurable position and orientation errors associated with path following. Two important results are derived. It is indicated that for path following, for this class of vehicle at low speeds, the equations of motion based on system kinematics are sufficient for control purposes. Furthermore, if the differential point (the rear axle middle point) is considered for position error measurement, then the equations governing the steering action in such a vehicle are similar to those of a double integrator.