Passive and wireless acoustic wave accelerometer

• US 20060283247A1
• Filed: 06/16/2005
• Published: 12/21/2006
• Est. Priority Date: 06/16/2005
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Rahman, Aziz, Liu, James ZT
• Granted Patent: US 7,243,544 B2
• Time in Patent Office: Days
• US Class Current: 73/514.10
• CPC Class Codes: G01P 15/0975 by acoustic surface wave resonators or delay lines

Abstract

An acoustic wave acceleration sensor comprises an acoustic wave device including a plate that functions as a propagation medium and at least one interdigital transducer configured upon the plate. One or more antennas can be integrated with the acoustic wave device, wherein the antenna(s) communicates with interdigital transducers. Such antennas can receive wireless interrogation signals and transmit signals indicative of acceleration data.

Claims

1. An acceleration sensor, comprising:

an acoustic wave device including a plate that functions as a propagation medium and at least one interdigital transducer configured upon said plate; and

an antenna integrated with said acoustic wave device, wherein said antenna communicates with said at least one interdigital transducer such that said antenna receives and transmits signals indicative of acceleration data, wherein said acoustic wave device is clamped at one end of said plate to an object under an acceleration and submitted to a force at said free end of said plate; and

an inertial mass fixed at said free end of said plate such that when said acceleration is applied to said acoustic wave device, said acceleration is converted to a proportional force through utilization of said inertial mass fixed at said free end of said plate, wherein said proportional force interacts with an acoustic propagation through a plurality of forces applied to said propagation medium, thereby generating signals indicative of said acceleration data for wireless transmission from said antenna.

2. The sensor of claim 1 wherein said at least one interdigital transducer comprises a SAW filter electrode, wherein a frequency of said SAW filter electrode comprises data indicative of said acceleration

3. The sensor of claim 1 wherein said at least one interdigital transducer comprises a SAW-R electrode, wherein a frequency of said SAW-R electrode comprises data indicative of said acceleration

4. The sensor of claim 1 wherein said at least one interdigital transducer comprises a SAW-DL electrode, wherein a phase of said SAW DL electrode comprises data indicative of said acceleration

5. The sensor of claim 1 wherein said plate comprises a piezoelectric substrate.

6. The sensor of claim 1 wherein said acceleration data for wireless transmission from said antenna is based on at least one parameter change produced in an acoustic phase velocity associated with said acoustic wave device by a presence of a static mechanical polarization applied to said propagation medium.

7. The sensor of claim 1 wherein said acceleration data for wireless transmission from said antenna is based on at least one parameter change produced in an acoustic phase velocity associated with said acoustic wave device by a presence of a slowly varying mechanical polarization applied to said propagation medium.

8. An acceleration sensor, comprising:

an acoustic wave device including a plate that functions as a propagation medium and at least one interdigital transducer configured upon said plate;

an antenna integrated with said acoustic wave device, wherein said antenna communicates with said at least one interdigital transducer such that said antenna receives and transmits signals indicative of acceleration data, wherein said acoustic wave device is clamped at one end of said plate to an object under an acceleration and submitted to a force at said free end of said plate; and

an etched rectangular frame-shaped channel located on a back side of said at least one interdigital transducer, such that a mass within said etched rectangular frame-shaped channel possesses a high sensitivity to said acceleration when said acceleration is applied to said acoustic wave device; and

wherein said acceleration is converted to a proportional force through utilization of said mass fixed at said free end of said plate, wherein said proportional force interacts with an acoustic propagation through a plurality of forces applied to said propagation medium, thereby generating signals indicative of said acceleration data for wireless transmission from said antenna.

9. The sensor of claim 8 wherein said at least one inter-digital transducer comprises a SAW filter electrode, wherein a frequency of said SAW filter electrode comprises data indicative of said acceleration

10. The sensor of claim 8 wherein said at least one inter-digital transducer comprises a SAW-R electrode, wherein a frequency of said SAW-R electrode comprises data indicative of said acceleration

11. The sensor of claim 8 wherein said at least one inter-digital transducer comprises a SAW-DL electrode, wherein a phase of said SAW-DL electrode comprises data indicative of said acceleration

12. The sensor of claim 8 wherein said plate comprises a piezoelectric substrate.

13. The sensor of claim 8 wherein said acceleration data for wireless transmission from said antenna is based on at least one parameter change produced in an acoustic phase velocity associated with said acoustic wave device by a presence of a static mechanical polarization applied to said propagation medium.

14. The sensor of claim 8 wherein said acceleration data for wireless transmission from said antenna is based on at least one parameter change produced in an acoustic phase velocity associated with said acoustic wave device by a presence of a slowly varying mechanical polarization applied to said propagation medium.

15. An acceleration sensor, comprising:

an acoustic wave device including a plate that functions as a propagation medium and at least one interdigital transducer configured upon said plate; and

an antenna integrated with said acoustic wave device, wherein said antenna communicates with said at least one interdigital transducer such that said antenna receives and transmits signals indicative of acceleration data, wherein said acoustic wave device is clamped at one end of said plate to an object under an acceleration and submitted to a force at said free end of said plate; and

a coating with a heavy mass such that said acoustic wave sensor possesses a high sensitivity to said acceleration when said acceleration is applied to said acoustic wave device, such that said acceleration is converted to a proportional force through utilization of said mass fixed at said free end of said plate, wherein said proportional force interacts with an acoustic propagation through a plurality of forces applied to said propagation medium, thereby generating signals indicative of said acceleration data for wireless transmission from said antenna.

16. The sensor of claim 15 wherein said at least one inter-digital transducer comprises a SAW filter electrode, wherein a frequency of said a SAW filter electrode comprises data indicative of said acceleration

17. The sensor of claim 15 wherein said at least one inter-digital transducer comprises a SAW-R electrode, wherein a frequency of said SAW-R electrode comprises data indicative of said acceleration

18. The sensor of claim 15 wherein said at least one inter-digital transducer comprises a SAW-DL electrode, wherein a phase of said SAW-DL electrode comprises data indicative of said acceleration

19. The sensor of claim 15 wherein said plate comprises a piezoelectric substrate.

20. The sensor of claim 15 wherein said acceleration data for wireless transmission from said antenna is based on at least one parameter change produced in an acoustic phase velocity associated with said acoustic wave device by a presence of a static mechanical polarization applied to said propagation medium.

21. The sensor of claim 15 wherein said acceleration data for wireless transmission from said antenna is based on at least one parameter change produced in an acoustic phase velocity associated with said acoustic wave device by a presence of a slowly varying mechanical polarization applied to said propagation medium.