Abstract: A vibrating structure angular rate sensor comprises a substrate; a plurality of supporting structures fixed to the substrate; an annular member flexibly supported by the plurality of supporting structures 204; a drive system arranged to apply a periodic driving force such that the annular member 202 oscillates, in use, in a primary mode of vibration at a resonant frequency f1, with an amplitude of motion that generates a restoring force from the plurality of supporting structures 204; and a pick-off system arranged to determine the amplitude of motion of a secondary mode of vibration at a resonant frequency f2, in which oscillation of the annular member 202 is induced by the Coriolis force resulting from an angular rate experienced by the sensor 100. In use, the restoring force has a non-linear relationship with the amplitude of motion and a number p of supporting structures is selected such that f1=f2.

Abstract: A vibrating structure angular rate sensor comprises a substrate; a plurality of supporting structures fixed to the substrate; an annular member flexibly supported by the plurality of supporting structures 204; a drive system arranged to apply a periodic driving force such that the annular member 202 oscillates, in use, in a primary mode of vibration at a resonant frequency f1, with an amplitude of motion that generates a restoring force from the plurality of supporting structures 204; and a pick-off system arranged to determine the amplitude of motion of a secondary mode of vibration at a resonant frequency f2, in which oscillation of the annular member 202 is induced by the Coriolis force resulting from an angular rate experienced by the sensor 100. In use, the restoring force has a non-linear relationship with the amplitude of motion and a number p of supporting structures is selected such that f1=f2.