This work discusses a road-tyre friction estimator considering combined tyre slip. The friction estimator design is motivated by its importance in vehicle dynamics control as accurate friction estimation can improve performance and safety. The estimator uses tyre force measurements from Load Sensing Bearing (LSB) technology and does not rely on parameterized tyre model. The tyre force measurements benefit the estimator mainly because of the uncertainties and nonlinearities of the tyre force characteristics. The proposed estimator uses tyre slip and tyre force representations where the longitudinal and lateral tyre slips and forces are combined into a single tyre slip and tyre force values. This representation makes the method effective during pure longitudinal dynamics, pure lateral dynamics and for combined slip. In addition, individual tyre-road friction estimation is possible with the proposed estimator and a computationally inexpensive algorithm, suitable for real-time implementation, is used to estimate the friction. The estimator is studied in simulation during pure braking, pure cornering and for combined slip. Further, the estimator is simulated in closed loop with a yaw rate controller to study whether the estimator improves vehicle safety. Finally the estimator is validated using test data from several maneuvers performed on a test vehicle instrumented with LSB technology.

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Research of the past century has demonstrated that wheel camber regulation provides great potential to improve vehicle safety and performance. This led to the development of various prototypes of the camber mechanisms over the last decade. An overview of the existing prototypes is discussed in the presented paper. Most of the investigations related to camber control cover open-loop maneuvers to evaluate a vehicle response. However, a driver’s perception and his reaction can be the most critical factor during vehicle operation. Therefore, the research goal of the presented study is to assess an influence of active camber control on steering feel and driving performance using a driving simulator. In the proposed investigation, a dSPACE ASM vehicle model has been extended by introducing advanced models of steering system and active camber regulation. The steering system describes dynamics of steering components (upper and lower columns, torsion bar, steering rack and others). It is parameterized and validated for a middle-size passenger vehicle. Camber actuation mechanism is based on the most relevant existing prototype. The proposed camber control system is based on lateral acceleration and yaw rate. Twelve participants drove a driving task with passive and active camber regulation. The results show that active camber control plays a significant role in the subjective assessment of steering feel, and has a corresponding effect on objective driving performance.@en

Research efforts in both academia and industry connected with the development and implementation of autonomous driving systems are increasing exponentially in last years. The project designed and presented is part of the so called Dutch Automated Vehicle Initiative (DAVI) which aims to investigate, improve and demonstrate automated driving on public roads. The work presented focuses on the path planning and following in highway environment, presenting a novel approach. A modular solution was designed, where the evaluation of risk is implemented in a path planner that select the optimal trajectory among a discrete set of feasible ones in term of comfort. The tracking is performed through a non linear model predictive controller (NMPC), that also consider collision-risk assessment information. In order to test critical situations that can commonly occur, several scenarios were designed and tested through extensive numerical simulations. Simulation results demonstrate that the proposed system is capable of dealing with complex driving situation, maintaining a human-like behavior.@en