Simulation of the critical modes of automatically connected four-wheel drive systems detected in operation

Abstract

Dynamics, driving stability and passability of a vehicle can be enhanced with the help of active torque distribution systems along the vehicle axles. The efficiency of such systems, especially in the absence of an interaxle differential, depends mainly on the controlling algorithm of the interaxle multi-plate clutch. When studying the history of systems and algorithms of active torque distribution along the vehicle axles, some problems were identified to have encountered the first developers of those systems in operation. Since that time there appeared many programs for mathematical modeling of physical systems, which allowed testing and debugging of the algorithm developed for a virtual object. The article has been written to demonstrate one of the variants of modeling application as a stage of control algorithms development for technical systems. For this purpose some problem situations which the first developers of active torque distribution systems had encountered were simulated. Then both published and own variants of the problems in question solution were checked. Particular attention was paid to the case of self-oscillation in motion on a slippery surface and the occurrence of vibrations when the vehicle was muffled and stopped after a turn. The paper presents the schemes of simulation models performed in the LMS Amesim computational complex, the results of modeling in the form of graphs, the analysis of results, the analysis of published possible solutions to these problems, as well as the author's solutions.