A generalized sufficient condition for time-optimal control

This paper presents a sufficient optimality condition for timeoptimal feedback control, which generalizes the existing sufficient conditions, i.e., the HJB equation and a Lyapunov-based condition derived in [12]. The new condition is satisfied by a class of piecewise C¹ continuous functions, termed generalized value functions. It admits a larger class of functions, such as bounded functions, than the existing conditions as demonstrated in an example. The generalized condition might, therefore, be useful in solving for the time-optimal feedback control of nonlinear systems such as robotic manipulators.