The front control panel. The throttle and shifter for the front Patterson drive are mounted here. The Cycle Analyst display on the top shows speed and monitors battery level and motor performance. The joystick is used to control the rear servo-actuated steering.
Because of the size of the machine and the wheels, four-wheel steering became a necessity to be able to maneuver it. The four-wheel steering was the hardest thing to figure out. We tried several different implementations and finally settled on using a computer-controlled servo for the rear wheel steering.
The front steering was also a challenge. The large wheels made any kind of lever actuated controls impossible to get in the right position. We initially decided on another servo for the front steering, but decided that for safety reasons (in case the battery died) we needed a manual setup. This custom geared pivot made it possible. The lower shaft connects to the rack and pinion system, while the upper shaft connects to the steering wheel and can be articulated as needed.