Patent ID: 6546806
Filing Date: 2003-04-15
Classification: G01L

Abstract:
A force sensor having two measurement ranges, said force sensor comprising a load cell made of a shape memory alloy, a strain sensing system including a sensor attached to the load cell that deforms in response to a contact force placed upon the load cell to allow measurement of the contact force, a temperature modulation system that actively heats and cools the shape memory alloy, the temperature modulation system being in contact with the load cell to allow adjustment of the temperature of the load cell so as to place the shape memory alloy in either a martensite phase for measuring contact forces in a first range or an austenite phase for measuring contact forces in a second range, such that in the martensite phase the load cell is capable of measuring contact forces in the first range, and in the austenite phase the load cell is capable of measuring contact forces in the second range, and a temperature monitoring system in contact with the load cell to allow measurement of the temperature of the load cell.