Gang Shan Lin

US Patent:

20020066317, Jun 6, 2002

Filed:

Dec 6, 2000

Appl. No.:

09/730494

Inventors:

Gang Lin - Fremont CA, US

International Classification:

G08C019/00

US Classification:

073/504020, 073/504040

Abstract:

Yaw rate sensors are provided, the use of which permits quantitative measurement of yaw rate. The yaw rate sensor comprises at least a base, a first suspension and a second suspension with a proof mass supported between the two suspensions, which together form a resonator. The first suspension has a pair of thin-wire driving electrodes double side patterned on the surfaces. When a driving voltage is applied to the driving electrodes, it imposes an electric field to piezoelectrically induce a driving resonance. When the sensor is rotated around its sensing axis, the resonator will be forced to generate a sensing resonance out of the driving resonance plane to compensate the change in the linear momentum which must be conserved. The piezoelectric charge signal generated by the sensing resonance on the sensing electrodes which are double side patterned on the surfaces of the second suspension is used to detect the yaw rate. Specifically, the amplitude of the sensing resonance is in proportion to the yaw rate. The structure of the yaw rate sensors of this invention is suitable for mass production by lithographic micromachining techniques at low cost.