The goal of Christopher M. Schmidt-Wetekam was to build a robot with off-the-shelf parts for his graduate research project that could roll around and hop over obstacles like a motorized kangaroo on roller skates. His two-wheeled creation called “iHop” does just that, an accomplishment that won Schmidt-Wetekam, a UC San Diego graduate student, top honors at the Jacobs School of Engineering’s annual Research Expo on Feb. 21.