Patent ID: 7292951

Claim:
A method of compensating for hysteresis in a load cell, comprising: (a) pre-calibrating a load cell for hysteresis by: measuring load cell deflection under progressively increasing loads; determining a first set of coefficients correlating the deflection of the load cell to the measured load under the progressively increasing loads; measuring load cell deflection under progressively decreasing loads; determining a second set of coefficients correlating the deflection of the load cell to the measured load under the progressively decreasing loads; and then (b) compensating for hysteresis in the load cell, by: measuring load cell deflection at a particular load; selecting the first set of coefficients if the load on the load cell has been progressively increasing prior to the particular load being applied, or selecting the second set of coefficients if the load on the load cell has been progressively decreasing prior to the particular load being applied; and applying a formula using the selected first or second set of coefficients to the measured load cell deflection at the particular load, thereby determining an accurate load cell deflection, and thus compensating for hysteresis in the load cell.