Patent ID: 7017686

Claim:
A personal transporter propelled by a user, the personal transporter comprising: a. a platform for supporting the user; b. a ground-contacting module having a first ground-contacting element movable about an axis for propelling the platform with respect to an underlying surface; c. a power train for coupling power through solely mechanical means from the user to the ground-contacting element for impelling the ground-contacting element about its axis; d. a first sensor for sensing a value of a pitch variable of the personal transporter; e. a powered actuator for providing torque to the ground-contacting element in addition to any torque provided by the user; and f. a controller for governing the powered actuator based at least on the value of the pitch variable in such a manner as to maintain stable operation of the personal transporter in an operating position that would be unstable with respect to tipping in the fore-aft plane but for provision of torque to the ground-contacting element.