Real-time identification of road-bank angle using differential GPS

This brief presents a new approach to identify road-bank angle in real time using differential global positioning system (GPS)-based measurements. In the proposed approach, unknown vehicle parametric variations are decoupled from road-bank angle information by appropriate identification-oriented parameterization of the lumped disturbance. Three alternative estimation approaches are then developed using the parameterized model for real-time bank angle identification. These include a parameter identification algorithm for linear systems, an adaptive observer and a disturbance observer combined with an adaptive gradient law. The estimators are augmented with intuitive projection algorithms in order to enhance the efficacy of the algorithms. The performance and accuracy of the proposed algorithms is evaluated by both numerical simulation and experimental results. The advantages and disadvantages of each of the three estimation algorithms are described.