Nano-resonator inertial sensor assembly

• US 8,584,524 B2
• Filed: 12/13/2011
• Issued: 11/19/2013
• Est. Priority Date: 10/21/2008
• Status: Expired due to Fees

• Current Assignee: PFG Ip, LLC
• Original Assignee: ISC8 Incorporated
• Inventors: Hsu, Ying
• Primary Examiner(s): KWOK, HELEN C
• Application Number:
  US13/324,573
• Publication Number:
  US 20130019682A1
• Time in Patent Office: 707 Days
• Field of Search: 735/142.9, 735/141.6, 735/143.8, 735/143.6
• US Class Current: 73/514.29
• CPC Class Codes: G01C 19/5719 using planar vibrating masses driven in a translation vibration along an axis
• CPC Class Codes: G01C 19/5776 Signal processing not specific to any of the devices covered by groups G01C19/5607 - G01C19/5719
• CPC Class Codes: G01P 15/097 by vibratory elements

Abstract

The invention is a frequency modulated (FM) inertial sensing device and method which, in one embodiment, comprises an accelerometer having a proof mass coupled to a nano-resonator element. The nano-resonator element is oscillated at a first predetermined frequency, which may be a first resonant frequency, and is altered to oscillate at a second frequency, which may be a second resonant frequency, in response to a resultant force produced by the acceleration of the proof mass. The degree of change in nano-resonator element output frequency is sensed and processed using suitable processing circuitry as a change in acceleration.

Claims

1. An inertial sensor comprising:

a proof mass suspended on a centrally-disposed anchor by a plurality of micro-beams that are longitudinally disposed orthogonal to a direction of deflection of the sensor,

the proof mass coupled to a plurality of nano-resonators that are longitudinally disposed orthogonal to the direction of deflection,

the nano-resonators comprising a sense means and a drive means disposed on a first thickness of the nano-resonators,

the nano-resonators configured to be capable of being oscillated at a first predetermined frequency and configured to be capable of being altered to oscillate at a second frequency in response to a resultant force produced by an inertia of the proof mass.

2. An inertial sensor comprising:

a centrally-disposed anchor coupled to a substrate,

a proof mass having a second thickness coupled to the anchor and suspended over the substrate by means of at least one micro-beam that is longitudinally disposed orthogonal to a direction of deflection of the sensor,

a plurality of nano-resonators each having a first thickness,

the plurality of nano-resonators coupled to the anchor and to the proof mass,

the nano-resonators longitudinally disposed orthogonal to the direction of deflection,

nano-resonator drive means for driving the nano-resonators at a first predetermined frequency, and,

sensing means for detecting nano-resonator output frequency.

3. The inertial sensor of claim 2 wherein the second thickness is at least about ten times greater than the first thickness.

4. The inertial sensor of claim 2 wherein the second thickness is greater than about 100 microns and the first thickness is less than about one micron.

5. The inertial sensor of claim 2 wherein the sensor further comprises proof mass drive means for oscillating the proof mass at a proof mass frequency,

the proof mass and the nano-resonator element coupled whereby the proof mass frequency modulates the nano-resonator output frequency.

6. A method for sensing acceleration comprising the steps of:

providing a proof mass suspended on a centrally-disposed anchor by a plurality of micro-beams that are longitudinally disposed orthogonal to a direction of deflection of a sensor,

the proof mass coupled to it plurality of nano-resonators that are longitudinally disposed to the direction of deflection,

the nano-resonators comprising a sense means and a drive means,

oscillating the nano-resonator at a first predetermined frequency,

detecting the output frequency of the nano-resonators in response to an acceleration of the proof mass, and,

measuring a rate of acceleration based on a shift in frequency from the first predetermined frequency to the output frequency.