Control of Vehicle’s Mixed Longitudinal and Lateral Stability with Engine Dynamics Using Super Twisting Control Algorithm

Vehicle stability control is one of the most important subjects in control engineering field. Many research activities have been done to develop more comfort and safe travel for passengers. In this paper, vehicle mixed stability in longitudinal and lateral motion has been investigated. Full model of vehicle (4 wheel) is considered to extract the dynamic equations. Dugoff’s nonlinear model has been used to simulate the behavior of tyres and road, and Cho’s engine model with two state variables has been used for vehicle power system simulation, so it makes the input torque to wheels to be more realistic. Because of the good robustness properties of sliding mode control the second order sliding mode with super-twisting algorithm has been used for calculation of control inputs. This method is proved to be so appropriate and useful in the case of uncertainty in complicated vehicle dynamic model and multiple disturbances in vehicle motion. Engine throttle angle and yaw moment have been considered as longitudinal system and lateral system control inputs respectively. Longitudinal slip coefficient and yaw rate are considered as system output. Simulation results shows the effectiveness of the proposed method.