A Multi-Layer Drifting Controller for All-Wheel Drive Vehicles Beyond Driving Limits

The development of drifting control technology is crucial when it comes to the advancement of autonomous driving and active safety. This article presents the development of a multilayer autonomous drifting controller that aims to stabilize the drifting states (the sideslip angle, yaw rate, and velocity) of all-wheel drive (AWD) vehicles simultaneously. The steady-state drifting analysis, which is based on nonlinear four-wheel dynamics equilibria, reveals that both the saturation of the vehicle's four tires and the deep sideslip are the primary characteristics of drifting AWD vehicles. To achieve autonomous control of drifting AWD vehicles, we designed a multilayer drifting controller that consists of three progressive layers, i.e., vehicle states stabilization, dynamics model inversion, and chassis mapping. Upon testing the controller on a 1:5 scale AWD vehicle, we verified the effectiveness and robustness of our controller, with an average sideslip angle of up to 70°.