A novel description of dual-envelop-oriented path tracking issue is presented for fully automated vehicles which considers shape of vehicle as inner-envelop (I-ENV) and feasible road region as outer-envelop (O-ENV). Then implicit linear model predictive control (MPC) approach is proposed to design moving horizon path tracking controller in order to solve the situations that may cause collision and run out of road in traditional path tracking method. The proposed MPC controller employed varied sample time and varied prediction horizon and could deal with modelling error effectively. In order to specify the effectiveness of the proposed dual-envelop-oriented moving horizon path tracking method, veDYNA-Simulink joint simulations in different running conditions are carried out. The results illustrate that the proposed path tracking scheme performs well in tracking the desired path, and could increase path tracking precision effectively.

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Considering the nonlinear characteristics, model uncertainties and the time-varying road conditions of ground vehicles, a novel traction controller for ground vehicles is presented using nonlinear robust modified sliding mode control method to solve the problem of skid braking and spin acceleration. The current wheel slip could be controlled at the optimal value using this method, so that it could improve the safety and stability of ground vehicles in slippery road conditions. Due to the optimal value of the wheel slip depends on road conditions, the so-called Burckhardt's tire model is adopted to make online calculation. In order to validate the effectiveness of the proposed method, simulations in different road conditions are carried out, and a series of simulation results indicate that the wheel slip tracking controller could obtained fairly good performance.