Abstract:
PROBLEM TO BE SOLVED: To provide a small sensor which can detect deformation of an object, and in which an electric circuit is incorporated.SOLUTION: A MEMS sensor is constituted of: a wafer substrate 1 having flexibility; and a MEMS vibrator 3 provided on a principal plane of the wafer substrate 1. The MEMS vibrator 3 includes; a lower electrode 13e as a first electrode; and an upper electrode 14e as a second electrode having a movable part, the upper electrode 14e vibrates by electrostatic force of an electric charge to be generated in accordance with AC voltage to be applied between both electrodes, and a resonance frequency signal unique to the vibrator is output. Furthermore, when the wafer substrate 1 is deformed by applying external force thereto, the MEMS vibrator 3 also deforms, and a resonance frequency of the MEMS vibrator 3 can be changed due to a change in a spring constant of the upper electrode 14e caused by distortion of a fixed part of the upper electrode 14e in accordance with deformation of the MEMS vibrator 3.
Abstract:
The force measuring device consists of two horizontal cantilever members located parallel with each other in a common vertical plane. A weighing cradle is attached to the free end of the first member and a metal string stretched between the free ends of both members. The string is placed between a pair of magnetic poles so that it vibrates at its inherent frequency functionally relating to its tension and a load applied to the weighing cradle. The frequency of the string is measured and the value of the applied load is calculated by an electronic calculating circuit.