Path Planning and Following Control of Autonomous Bus Under Time-Varying Parameters Against Parametric Uncertainties and External Disturbances

Path planning and path following are key technologies for autonomous vehicles. Strong nonlinearity, coupling characteristics, parametric uncertainties, external disturbances, and complicated driving scenarios put forward great challenges in estimation, control, and optimization of autonomous vehicles. Multi-dimension information utilization offers an effective solution to cope with the foregoing challenges. The presented research proposes a path planning and tracking framework for optimal design and regulation of control variables for collision avoidance and active guidance system, aiming to improve tracking performance and system robustness. For path planning approach, a virtual harmful potential field in 3 dimension (3D) is built to provide a collision-free trajectory as a reference path for path following, depending on vehicle kinematic model and boundary conditions of roads. A linear parameter-varying, polytopic vehicle lateral model is developed to address the issues of time-variable longitudinal speeds and preview distance on vehicle lateral stability management. Further, a strong robust gain-scheduling path following control approach based on linear matrix inequality methodology is proposed to tackle problems relating to characteristics of temporal variations, parametric uncertainties and external disturbances. Comparisons study under the TruckMaker/Xpack4-RapidECU joint HIL platform demonstrate that both tracking precision and high robustness to parametric uncertainties and external disturbances are superior than model predictive control method. The presented path following method provides an important insight into exploiting the robust control method's favorable merits while guaranteeing its computing efficiency.