ABSTRACT
A peculiarity of off-road vehicles is that their mobility depends not only on the total
power provided by the engine, but also on its distribution among the driven
axles/wheels. In turn, this distribution is largely dominated by the drivetrain
architecture and the inherent characteristics of the torque distribution devices.
Among the wide variations of torque distribution devices, controlled differential can
offer variable bias ratios over the entire operation of the vehicle.
This paper presents an electronically controlled device to modulate the applied force
over multi-plate clutches which are placed between the driven axle and stationary
hub. For the driving condition over split adhesion roads, the proposed device brakes
the spinning wheel over low adhesion side and therefore bias more torque to the
other wheel with good adhesion side. This would improve off-road mobility and save
the power losses on low traction wheels. A special test rig has been devised to
experimentally investigate the characteristics of the proposed device. The rig
compromises measurements of speed and torque applied to each wheel.
The obtained results show that various benefits could be gained when a controllable
multi plate clutch is implemented with simple differential driving axle. The system can
offer power saving than both passive differential and even limited slip differential.