A pedal (2) for use with both feet wherein depression with one foot causes acceleration and depression by the other foot causes braking. The pedal pivots about a medial line of a user. A system to detect a change in the pivot direction of the pedal is also included, the system automatically switching between acceleration and braking in response to a detected change.

Certain embodiments provide a head array system for a power wheelchair, including a head array body and one or more lateral arms. The head array body includes shafts. Each of the shafts includes lateral arm receiving sections. The one or more lateral arms are detachably coupled to one of the lateral arm receiving sections of one of the shafts.