Patent ID: 8857920

Claim:
An obstacle traversing wheel assembly comprising: at least one primary wheel member, each primary wheel member mounted with respect to a corresponding primary axis of rotation, each primary wheel member capable of rolling engagement with a supporting surface; at least one secondary wheel member mounted with respect to a secondary axis of rotation; at least five supporting-surface-engaging portions for enabling the obstacle traversing wheel assembly to traverse an obstacle by imparting climbing movement to the at least one primary wheel member in response to engagement with the obstacle, the at least five supporting-surface-engaging portions associated with one of the at least one primary wheel member and the at least one secondary wheel member; and a plurality of swivel mounts, each swivel mount connecting one of the at least one primary wheel members with respect to the at least one secondary wheel member, each swivel mount having a swivel axis of rotation mounted in fixed orientation perpendicular to and skewed from the secondary axis of rotation.