(under the class definition) Apparatus comprising ground engaging feet or plates operating by a step-by-step movement during the forward travel of the apparatus.
SEE OR SEARCH CLASS
180, Motor Vehicles,
187, for a motor vehicle provided with one or more ski-like or runner members and wherein the vehicle has at least one surface-engaging propulsion element of a type which shuffles along the surface; and subclasses 8.1+ for a motor vehicle provided with a special driving device of the mechanical leg type.
301, Land Vehicles: Wheels and Axles,
41.1+, especially subclasses 45+ for traction increasing devices for wheels. See the class definition of Class 305 for the line between these devices and the steppers of Class 305.