Development of a New Electronically Controlled 4WD System: Toyota Active Torque Control 4WD

In Japan, Multipurpose vehicles (MPVs) are growing in popularity while sedan popularity is falling. Four wheel drive (4WD) systems on MPVs require wide range torque distribution because the vertical load distribution on the front and rear tires changes greatly. In order to satisfy this requirement for 4WD , Toyota Motor Corporation and Toyoda Machine Works LTD. have developed a new electronically controlled 4WD system named “Active Torque Control 4WD”. This system, by optimum driving force distribution, provides both good handling characteristics and low fuel consumption. And it enables compact drive-line size and light weight.

This paper describes the development aims of the new system, its construction, its control and technological features.