Performance of a Power-Driven Trailer During Motion Uphill and Downhill

Abstract

The authers studied an estimating method of hill-climbing ability of a power-driven trailer with the peripheral speed difference between the tractor and trailer wheels on the concrete road. The results were as follows:
(1) By means of obtaining the λ-S diagram, both slippages of the tractor and trailer wheels are given at the intersection of two curved lines given by Eqns (12), (14) or (15) and (22), when there is a peripheral speed difference between the tractor and trailer wheels. (Fig. 3)
The results calculated gave good agreement with the experimental results. (Fig. 4, 5)
(2) The more the laden weight of the trailer or the lighter the weight of tractor, the smallerbecome the wheel loads of the tractor due to the driving reaction force of the trailer. Consequently tractor loses the steering control ability. Conditions preventing this phenomenon are given by Eqns (26) and (27), and the weight ratio (tractor/trailer) satisfying this conditions is more than about 1.7 in case of the concrete road at the laden weights 880kg of the trailer. (Fig. 9)
(3) The maximum climbing abilities on the concrete road are 29° for the four-wheel drive tractor with the driven trailer, 28° for the front-wheel drive tractor with the driven trailer, 20° for the rear-wheel drive tractor with the driven trailer, and 9° for the rear-wheel drive tractor with the undriven trailer. (Fig. 8)