Development of algorithms for active torque distribution along the vehicle axes

Abstract

Dynamics, road-holding ability and passability of a vehicle can be enhanced with the help of active torque distribution along the vehicle axles. The efficiency of such systems, especially if an inter-axle differential is absent, depends mainly on the controlling algorithm of the inter-axle multi-plate clutch. The article considers the existing algorithms for distributing torque along the vehicle axles. These algorithms are considered from the point of view of their over time changes caused by defects discovered in vehicle operation and with regard to the electronic computing development. The study of torque distribution algorithms development is based on published patents on torque distribution systems, control algorithms and on individual solutions of problems identified in vehicle operation. This study is necessary to develop other efficient algorithms for the torque distribution. The most suitable objects for the study were the algorithms of Nissan torque distribution system. These systems were chosen for two reasons: firstly, because of the long life development of the torque distribution system, which began in 1988, the company became one of the pioneers to develop the automatically connected all-wheel drive; secondly, in the course of its development the original algorithm has undergone many changes and various search solutions, which are reflected in published patents and open for automotive companies. As a result of the review, both prospective and deadlock ways of torque distribution algorithms development have been identified. The operation peculiarities of the vehicles with an automatically connected all-wheel drive as well as other problems can be avoided by developing a new algorithm.