Combined performance and stability optimisation via central transfer case active control in four-wheeled vehicles

New driveline architectures endowed with torque biasing devices, such as active differentials and active transfer cases, have made available a new generation of on-demand four-wheel-drive vehicles which allow designing control systems capable of altering the car behaviour dictated from its mechanical layout, e.g., under- and over-steering characteristic. This work proposes an active transfer case controller aimed at optimising vehicle performance in terms of amount of traction torque transmitted to the ground while guaranteeing vehicle stability and driveability by keeping the vehicle side-slip angle within safety bounds.