Patent ID: 7430491

Claim:
A method for estimating weight of a first vehicle during propulsion of the first vehicle along a generally horizontal underlying surface by and in unison with a second vehicle through which a portion of the weight of the first vehicle is borne on the underlying surface at a location spaced horizontally from an interface between the first vehicle and the underlying surface through which interface the remainder of the weight of the first vehicle is supported on the underlying surface, the method comprising: changing velocity of propulsion of the second vehicle from an initial velocity to a final velocity over a time interval; measuring force that the second vehicle needed to exert on the first vehicle along a line of propulsion during the time interval in order to change the velocity of propulsion from initial to final velocity; and processing, according to a first-vehicle-weight-yielding algorithm, data that includes data representing force obtained from the measuring step, data representing the portion of the weight of the first vehicle borne through the second vehicle, data representing the change in velocity of propulsion, data representing length of the interval of time, and data representing coefficient of friction of the interface, to yield an estimate of weight of the first vehicle.