Abstract:

In this paper, a novel electronic brake booster and an accurate pressure control method for engineering are put forward and consider the shortcomings of the existing braking system in active braking for intelligent driving. Together with the hydraulic control unit, they are comprised of two working modes: active braking for automatic drive and passive braking for driver intervention. For wheel cylinder pressure control, we translate the control problem of pressure to position tracking. The strong nonlinearity and the load-dependent friction make the position tracking control of the electro-mechanical brake booster more challenging. Consequently, a modified PI control architecture is presented with techniques of cascaded three closed loop PI controller, friction compensation based on friction model, and gain scheduling. Finally, based on dSPACE, we carried out the rapid prototyping tests of active braking and hardware in the loop tests covering full speed ACC conditions. The results show that pressure control, acceleration control, and speed control achieve optimal performance.