Abstract:
This paper presents an efficient approach for
low-level control of an unmanned ground vehicle (UGV)
operating in rough terrains. In particular, it tackles with the
problem of overshoot in the vehicle braking system that
arises from severe nonlinearity and input time-delay. The
resultant high-performance and robustness of the control
system are achieved by cascading a sliding mode controller
(SMC) in series with a conventional PID controller. The idea
is based on modelling the system as a second order time-delay
system under PID control while the SMC is incorporated to
shape the control input for time-delay and nonlinearity
compensation. An output predictor is also employed here to
obtain the necessary information to realize the proposed
controller. The validity of the proposed approach is verified
through simulations for the braking system of UGVs
developed at our Centre.
