Patent ID: 8921717

Claim:
A system for determining weight and position of an object on a weighing surface, the system comprising: first, second, third, and fourth load cells having respective first, second, third, and fourth strain gauges configured to measure strain at the load cells caused by the object on the weighing surface; circuitry configured to simultaneously determine weight and position of the object on the weighing surface by obtaining a first electrical signal produced by the first strain gauge, a second electrical signal produced by the second strain gauge, a third electrical signal produced by the third strain gauge, and a fourth electrical signal produced by the fourth strain gauge and simultaneously: adding the first electrical signal, the second electrical signal, the third electrical signal, and the fourth electrical signal, to produce a sum electrical signal proportional to a total weight on the load cells, and subtracting from the sum electrical signal a tare value proportional to the total weight of the weighing surface to produce a tared electrical signal; subtracting a sum of the third electrical signal and the fourth electrical signal from a sum of the first electrical signal and the second electrical signal to determine a longitudinal value indicative of the position of a center of gravity of the object on the weighing surface relative to the locations of the first and third load cells and relative to the locations of the second and fourth load cells; and subtracting a sum of the second electrical signal and the fourth electrical signal from a sum of the first electrical signal and the third electrical signal to determine a lateral value indicative of the position of a center of gravity of the object on the weighing surface relative to the locations of the first and second load cells and relative to the locations of the third and fourth load cells; and a display to report the weight of the object based on the tared electrical signal, a longitudinal position of the object based on the determined longitudinal value, and lateral position of the object based on the determined lateral value.