ABSTRACT
Trailer-hitch load-transfer devices are commonly employed to redistribute the vertical tire loads in a car-trailer system thereby levelling the car and the trailer. It has been found in practice that the use of load-transfer devices has a significant effect on the handling characteristics of car-trailer systems. A mathematical model of a particular load-transfer device shows that the influence on vehicle handling is due to friction in the device which produces an articulation stiffness having a stlck-slip characteristic. Because of the definite beneficial effect on vehicle handling created by this articulation torque, the use of purely elastic articulation restraints is studied in depth. Both steady-state and transient response are considered using linear and non-linear vehicle models. Articulation stiffness is shown to be effective in stabilizing a car-trailer combination with a trailer-swing instability with little degradation of the steady-turning response.
