This study investigates the lane-keeping control of autonomous vehicles with an emphasis
on the digital delayed nature of the system. The vehicle dynamics are represented
using a kinematic bicycle model, and a hierarchical lane-keeping controller is introduced
with multiple delays in the feedback loop. An extension of the semidiscretization
method is presented, in order to perform the stability analysis of the digitally controlled
vehicle with multiple discrete time delays. The differences between the continuous
approximation and the exact consideration of discrete time delays are highlighted.
We show that in certain cases, neglecting the effects of quantization can lead to
significant inaccuracies, especially when tuning the lower-level controller. The results
are verified using a series of small-scale laboratory experiments.
