Ride comfort oriented integrated design of preview active suspension control and longitudinal velocity planning

Aiming for further improvement in ride comfort, a novel integrated system combining preview active suspension control with longitudinal velocity planning based on road height information is proposed. From the suspension control side, the presented semi-EMPC (Explicit Model Predictive Control)-based controller, which is augmented with preview road information, can make up for the shortcomings of traditional implicit MPC and explicit MPC, and achieve a balance between computational burden and memory usage, thus enhancing the practicality of implementing preview suspension in real-world applications. Adopting dynamic programming and quadratic programming algorithms, a longitudinal velocity planning method based on preview information is provided to overcome the vibration that cannot be effectively suppressed by single suspension control, thus expanding the dimension of ride comfort improvement from the original vertical dimension alone to both longitudinal and vertical dimensions. Throughout the design process, the transformation of pavement information among spatial, time, and frequency domains has been regarded as a bridge to combine two systems, thus handling the complex coupling between above two highly interdependent systems. Experiments in the Quanser active suspension plant have been conducted to verify the superiority of semi-EMPC with preview. The integrated approach is simulated in Carsim and shows a significant improvement over single suspension control.