Abstract: Tethered trailer vehicle is a non professional tractor that drags an unpowered vehicle with hemp rope. This conduct has many problems: poor operating stability, and high incidence of traffic accident. A nonlinear dynamic model for longitudinal, lateral, and yaw motions was developed. The model considers nonlinearity through a modified Dugoff's tire friction model, and is seven-degree-of-freedom. A new nonlinear tethered tractor-trailer combination model was created to simulate critical parameters which would cause unstable state. Then, a trailer front-wheel steering feedback control strategy was derived with the goal of improving stability and trajectory tracking feature of the tractor-trailer system. The comparison of the simulation results for tension of the hemp rope, trajectory feature, and handling stability clearly demonstrates the efficacy of feedback control for the tethered tractor-trailer combination.

Key words: nonlinear vehicle model, rope-dragged tractor model, feedback control, simulation