Broad field motion detector

• US 20050073412A1
• Filed: 11/04/2004
• Published: 04/07/2005
• Est. Priority Date: 06/05/2002
• Status: Active Grant

• Current Assignee: The Watt Stopper Incorporated (Legrand SA)
• Original Assignee: The Watt Stopper Incorporated (Legrand SA)
• Inventors: Viala, Roar, Johnston, Kendall Ryan
• Granted Patent: US 7,277,012 B2
• Time in Patent Office: Days
• US Class Current: 340/552
• CPC Class Codes: G08B 13/1618 using ultrasonic detection means

Abstract

A motion sensing system device and method which utilize dispersed ultrasonic radiation is disclosed. The system preferably comprises a low profile sensor unit configured to couple to a ceiling position. The sensor unit comprises an ultrasonic transmitter and an ultrasonic receiver and a pair of acoustic reflectors positioned in a transmitting path of the ultrasonic transmitter and a receiving path of the ultrasonic receiver for generating and detecting the ultrasonic radiation in a broadcast field. The acoustic reflectors preferably comprise cones, conical cross-sections and/or combinations thereof which are integral with the ultrasonic transmitter and the ultrasonic receiver and/or are coupled to a housing structure for positioning the acoustic reflectors in the transmitting and/or receiving paths. The sensor unit also preferably comprises a circuit for driving the transmitter and for detecting motion by detecting changes in the receiver signal. In further embodiments, the system also includes an infrared sensor and is configured to generate a response based on the combination of changes in the receiver signal and a signal form the infrared sensor.

Claims

1. A sensor comprising:

a. a sensor unit comprising a transmitter for emitting ultrasonic radiation and a receiver for detecting the ultrasonic radiation; and

b. an acoustic propagation modulator configured for dispersing the ultrasonic radiation emitted and focusing the ultrasonic radiation received to detect motion.

2. The sensor of claim 1, wherein the transmitter transmits ultrasonic radiation at a frequency of 20 Kilohertz or above.

3. The sensor of claim 1, further comprising a housing configured for coupling the sensor to a ceiling position.

4. The sensor of claim 1, wherein the sensor unit comprises a circuit in electrical communication with the transmitter and the receiver, the circuit being configured to drive the transmitter and generate a receiving signal from the receiver.

5. The sensor of claim 3, wherein the acoustic propagation modulator is coupled to the housing.

6. The sensor of claim 1, wherein the acoustic propagation modulator comprises a pair of acoustic reflectors with sloped walls for positioning in a transmitting path of the transmitter and a receiving path of the receiver.

7. The sensor of claim 6, wherein the pair of acoustic reflectors comprise one or more conical cross-sections.

8. The sensor of claim 7, wherein the one or more conical cross-sections are concentrically positioned.

9. The sensor of claim 6, wherein the matched pair of acoustic reflectors comprise cone members.

10. The sensor of claim 4, wherein the circuit is configured to generate a response when changes in the ultrasonic radiation are detected.

11. The sensor of claim 10, wherein the response is a response selected from the group consisting of operating, sounding an alarm and initiating a telephone call.

12. A detector comprising:

a. means for emitting a wide angle ultrasonic wave;

b. means for receiving the wide angle ultrasonic wave; and

c. means for detecting changes in the wide angle ultrasonic wave.

13. The detector of claim 12, wherein the means for emitting a wide angle ultrasonic wave comprises:

a. an ultrasonic transmitter; and

b. an acoustic reflector positioned in a transmitting path of the ultrasonic transmitter, such that the ultrasonic wave generated therefrom is dispersed.

14. The detector of claim 13, wherein the means for receiving the wide angle ultrasonic wave comprises:

a. an ultrasonic receiver; and

b. a complementary acoustic reflector positioned in a receiving path of the ultrasonic receiver, such that the ultrasonic wave received is focused towards the receiver.

15. The detector of claim 14, wherein the acoustic reflector and the complementary acoustic reflector comprise one of more conical cross-sections.

16. The detector of claim 15, wherein the acoustic reflector and the complementary acoustic reflector comprise a cone member positioned centrally with respect to the one or more conical cross-sections.

17. The detector of claim 14, wherein the means for detecting changes in the wide angle ultrasonic wave comprises a circuit in electrical communication with the ultrasonic transmitter and the ultrasonic receiver, the circuit being configured to detect Doppler disturbances in the wide angle ultrasonic wave.

18. The detector of claim 12, further comprising an infrared sensor.

19. The detector of claim 12, wherein the means for emitting a wide angle ultrasonic wave emits ultrasonic radiation dispersed to a detection cone of 45 degrees or more.

20. The detector of claim 12, wherein the means for detecting changes in the wide angle ultrasonic wave comprises a circuit in electrical communication with the means for emitting and the means for receiving.

21. A motion detector comprising:

a. a transmitter unit with an acoustic reflector for producing a detection signal;

b. a receiver unit with a matched acoustic reflector for receiving the detection signal; and

c. a circuit coupled to the transmitter and the receiver for monitoring changes in the detection signal.

22. The motion detector of claim 21, further comprising a housing for housing the transmitter and the receiver, wherein the acoustic reflector and the matched acoustic reflector are coupled to the housing.

23. The motion detector of claim 21, wherein the acoustic reflector and the matched acoustic reflector are integral with the transmitter unit and the receiver unit, respectively.

24. A system comprising at least one motion detector comprising one or more wide angle transducers comprising acoustic modifiers for transmitting and receiving wide angle ultrasound waves.

25. The system of claim 24, wherein the acoustic modifiers comprises conical sections for deflecting ultrasonic radiation.

26. A method of detecting motion comprising:

a. generating a dispersed standing wave in a detection area;

b. monitoring the dispersed standing wave; and

c. detecting changes between the dispersed standing wave.

27. The method of claim 26, wherein generating a dispersed standing wave comprises driving an ultrasound transmitter at a frequency of 20,000 Hz or higher in a path of an acoustic reflector.

28. The method of claim 26, wherein monitoring the dispersed standing wave comprises sensing ultrasonic radiation with an ultrasonic receiver in a path of a matched acoustic reflector.

29. The method of claim 26, further comprising generating a response when changes in the dispersed standing wave.