Orientation Compensation for Initially Misaligned Caster Wheels

Abstract

This study presents an effective orientation compensation scheme for four-wheel vehicles with misaligned caster wheels in order to correct unexpected driving errors due to an unbalanced load or power. By accumulating angular differentials from the desired heading until achieving steady state driving, we obtain the net rotation angle and then compensate for it by controlling the speed difference of the two driving wheels on left and right sides. It is shown through experiments with an electric-powered wheelchair that the proposed orientation compensation scheme prevents transient swerve due to misaligned caster wheels and thus enables the vehicle to follow its expected driving path.