He has also worked as a member of the technical staff at MD Robotics, Canada and at NASA's Jet Propulsion Laboratory. His research typically concerns wheeled mobile robots operating in both structured and unstructured environments. His work spans many sub-specialties of mobile robots including control, position estimation, mapping, motion planning, simulation, and human interfaces. It also spans many application areas including outdoor unmanned ground vehicles, agricultural and mining vehicles, planetary rovers, and indoor automated guided vehicles.