Estimation of side slip and road bank angle using high-gain observer and higher-order sliding mode observer

The estimation of vehicle side slip and road bank angle is a significant issue in automotive research. In this work, to solve the state and unknown inputs estimation problem for the nonlinear vehicle dynamics, a high-gain observer in combination with higher-order sliding mode observer is employed. The high-gain observer is designed to overcome the parametric uncertainties and the higher-order sliding mode observer is employed for smooth estimation of unknown inputs. The combined observer does not impose the small-Lipschitz-constant condition on the system nonlinearity. Simulation results demonstrate the effectiveness of the proposed observer for estimation of the vehicle side slip and the road bank angle.