Optimising the braking performance via nonlinear analysis and bifurcation theory

This paper shows how the properties of a recently proposed nonlinear output feedback controller for active braking control systems can be exploited to optimise the braking performance. The control algorithm, in fact, allows to detect in which region of the friction curve the system is operating. Thus, via nonlinear analysis and bifurcation theory, we show that the closed-loop system exhibits a supercritical Hopf bifurcation. Based on this, we propose a way to estimate the current road conditions and to adapt the set-point in order to optimise the braking performance. A bifurcation diagram is also worked out to study the closed-loop dynamics modifications due to possible actuator faults or degradations.