Improvement of four-wheel drive vehicle controllability with a connected front axle through the redistribution of torque

Abstract

Currently, manufacturers of modern cars are constantly increasing the level of control over the parameters of the movement of wheeled vehicles, achieving the maximum level of stability and control. The use of various all-wheel drive systems is becoming increasingly relevant and expedient. The distribution of traction force on all wheels allows you to use the entire weight of the car as a coupling, which has a positive effect on the dynamic qualities of the car, terrain, and allows you to implement control algorithms that improve the handling and directional stability of the car. This article discusses the transmission with the possibility of redistribution of torque between both the front and rear axles, and between the wheels of the rear axle. The aim of the work is to substantiate the methods of control of the curvilinear motion of two-axle cars with different transmission schemes, providing an increase in their controllability. The control algorithms for the demolition of the front axle (understeer) and the rear axle skidding (oversteer) are considered. To solve the problem, the frequency method is used, in which the wheeled vehicle is considered as a multidimensional system. As a result, a method was proposed for improving the controllability of a two-axle car 4x4 with a link to the front axle and the redistribution of the torque between the wheels of the rear axle due to the redistribution of torque. The effectiveness and efficiency of the proposed method are proved by the methods of simulation of motion of two-axle 4x4 vehicles with a connected front axle and redistribution of torque between the wheels of the rear axle.