Multivariable robust controller for linear and angular velocities of Electrically-Powered Wheelchair using characteristic loci method

A MIMO description of an Electrically-Powered Wheelchair (EPW) is developed using kinematics of non-holonomic mobile robots in addition to DC electric motors dynamics. The dynamics is augmented with an innovative static matrix in order to achieve diagonal dominance and to obtain a reliable estimation of the plant. Characteristic loci method is exploited to design a MIMO controller for the augmented system to fulfill ride comfort, safety as well as acceptable maneuverability. A sufficient stability theorem is checked to ensure robust stability for whole uncertainty range. Experimental results obtained from microcontroller-based implementation of the controller verify robust stability and desired performance of the control system.