Radar devices for low power applications and bathroom fixtures

• US 20020171056A1
• Filed: 03/04/2002
• Published: 11/21/2002
• Est. Priority Date: 07/18/1997
• Status: Active Grant

• Current Assignee: Kohler Company
• Original Assignee: Kohler Company
• Inventors: Burnett, William R., Tervo, Steven M., Shafer, David C., Thomas, Carter J., Paese, Andrew J., Heinzmann, Fred Judson
• Granted Patent: US 6,568,655 B2
• Time in Patent Office: Days
• US Class Current: 251/129.04
• CPC Class Codes: E03C 1/057 touchless, i.e. using sensors
• CPC Class Codes: E03D 5/105 touchless, e.g. using sensors
• CPC Class Codes: G01S 13/0209 Systems with very large relative bandwidth, i.e. larger than 10 %, e.g. baseband, pulse, carrier-free, ultrawideband
• CPC Class Codes: G01S 13/04 Systems determining presence of a target based on relative movement of target G01S13/56
• CPC Class Codes: G01S 13/18 wherein range gates are used
• CPC Class Codes: G01S 13/22 using irregular pulse repetition frequency G01S13/12 takes precedence
• CPC Class Codes: G01S 13/56 for presence detection presence detection using near field arrangements G01V3/00, e.g. G01V3/08, G01V3/12; burglar, theft or intruder alarms with electrical actuation G08B13/22 - G08B13/26
• CPC Class Codes: G01S 13/88 Radar or analogous systems specially adapted for specific applications electromagnetic prospecting or detecting of objects, e.g. near-field detection, G01V3/00
• CPC Class Codes: G01S 7/03 Details of HF subsystems specially adapted therefor, e.g. common to transmitter and receiver
• CPC Class Codes: Y10T 137/0324 With control of flow by a condition or characteristic of a fluid

Abstract

A fluid flow device includes an actuator, an RF transmitter, a gated RF receiver, and a processor. The RF transmitter is configured and arranged to produce a plurality of pulses of RF energy spaced apart in time to form a sensor field. The gated RF receiver is configured and arranged to receive RF energy reflected by objects within the sensor field. The processor is coupled to the gated RF receiver for evaluating the reflected RF energy. The processor is also coupled to the actuator and is configured and arranged to activate the actuator in response to the reflected RF energy to control fluid flow. In addition, a new low power radar sensor operates by providing radar pulses that are non-uniformly spaced in time. In operation, a burst of pulses is initiated in the transmitter. Between each burst is a period of rest time in which the transmitter is not transmitting RF energy.

Claims

1. A fluid flow control device comprising:

an actuator for controlling fluid flow;

an RF transmitter configured and arranged to produce a plurality of pulses of RF energy spaced apart in time to form a sensor field;

a gated RF receiver configured and arranged to receive RF energy reflected by objects within the sensor field;

a processor coupled to the gated RF receiver for evaluating the reflected RF energy, wherein the processor is coupled to the actuator and is configured and arranged for activating the actuator in response to the reflected RF energy.

2. The fluid flow control device of claim 1, wherein the RF transmitter is configured and arranged to produce a plurality of pulses of RF energy non-uniformly spaced in time.

3. The fluid flow control device of claim 1, wherein the RF transmitter is configured and arranged to produce a plurality of bursts of pulses at a burst rate and having a burst width that is 5% or less than a time between bursts.

4. The fluid flow control device of claim 1, wherein the RF transmitter includes a transmitter pulse generator to produce a plurality of transmitter pulses at a pulse rate and an RF oscillator coupled to the transmitter pulse generator to produce the pulses or RF energy at the pulse rate in response to the transmitter pulses.

5. The fluid flow control device of claim 4, wherein the gated RF receiver includes a receiver pulse generator coupled to the transmitter pulse generator to produce receiver pulses to gate the RF receiver in response to the transmitter pulses.

6. The fluid flow control device of claim 5, wherein the gated RF receiver further includes a receiver delay line to delay the receiver pulses relative to the transmitter pulses.

7. The fluid flow control device of claim 6, wherein the receiver delay line is configured and arranged to provide at least two different delays.

8. The fluid flow control device of claim 1, wherein the RF transmitter includes a transmitter delay line to produce a delay in at least selected pulses of RF energy.

9. The fluid flow control device of claim 1, wherein the gated RF receiver is configured and arranged to receive reflected RF energy from at least two different ranges.

10. The fluid flow control device of claim 1, further comprising a valve coupled to the actuator, the actuator opening or closing the valve when activated.

11. The fluid flow control device of claim 1, wherein the processor is configured and arranged for detecting a presence of an object in the sensor field based on the reflected RF energy.

12. The fluid flow control device of claim 1, wherein the processor is configured and arranged for detecting motion of an object in the sensor field based on the reflected RF energy.

13. The fluid flow control device of claim 1, wherein the transmitter includes a directional transmitter antenna.

15. The method of claim 14, wherein transmitting a pulsed RF signal comprises transmitting a plurality of bursts of RF pulses at a burst rate and having a burst width that is 5% or less than a time between bursts.

16. The method of claim 14, wherein making an evaluation of the reflections of the RF signal includes making an evaluation of the reflections of the RF signal to determine one or more of:

a presence of a user in the sensor field, motion of the user in the sensor field, and direction of motion of the user in the sensor field.

18. The fixture of claim 17, wherein the fixture is a faucet, a urinal, or a toilet.

19. The fixture of claim 17, wherein the processor is configured and arranged to activate the actuator and open the valve when a user leaves the sensor field.

20. The fixture of claim 17, wherein the processor is configured and arranged to activate the actuator and open the valve when a user enters the sensor field.

21. The fixture of claim 17, wherein the sensor is disposed within the housing of the fixture.

22. The fixture of claim 17, wherein the sensor is disposed external to the housing of the fixture.

23. The fixture of claim 17, wherein the processor is configured and arranged to activate the actuator to open the valve after the processor determines that a user has entered the sensor field and then left the sensor field.

24. The fixture of claim 17, wherein the sensor is configured and arranged to form a first sensor field and a second sensor field, the second sensor field extending farther from the sensor than the first sensor field.

25. The fixture of claim 24, wherein the processor is configured and arranged to activate the actuator to open the valve after the processor determines that a user has entered the second sensor field, entered the first sensor field, approached the sensor, and subsequently left the second sensor field.

27. The sensor of claim 26, further comprising a processor for evaluating the RF energy sampled by the receiver sampler.

28. The sensor of claim 26, further comprising an actuator coupled to the processor and configured and arranged for activation by the processor in response to the RF energy sampled by the receiver sampler.

30. The method of claim 29, wherein evaluating the reflections comprises evaluating the reflections to determine at least one of:

the presence of a person in the sensor field, the movement of a person in the sensor field, and the direction of movement of a person in the sensor field.

14. A method of providing fluid flow in response to a user, comprising:

transmitting a pulsed RF signal to form a sensor field;

receiving reflections of the RF signal from objects within the sensor field;

making an evaluation of the reflections of the RF signal to determine a characteristic of a user; and

activating an actuator based on the evaluation of the reflections of the RF signal.

17. A fixture comprising:

a housing;

a valve for controlling fluid flow through the fixture;

an actuator for opening and closing the valve; and

a sensor for activating the actuator, the sensor includes

an RF transmitter configured and arranged to produce a plurality of pulses of RF energy spaced apart in time to form a sensor field,

a gated RF receiver configured and arranged to receive RF energy reflected by objects within the sensor field, and

a processor coupled to the gated RF receiver for evaluating the reflected RF energy, wherein the processor is coupled to the actuator and is configured and arranged for activating the actuator in response to the reflected RF energy.

26. A sensor comprising:

a burst initiator to provide a plurality of bursts at a burst rate and having a burst width that is 5% or less than a time between bursts;

a transmitter pulse generator coupled to the burst initiator to produce a plurality of transmitter pulses at a transmitter pulse rate and with a transmitter pulse width during each burst;

an RF oscillator coupled to the transmitter pulse generator to provide pulses of RF energy in response to the transmitter pulses;

a transmitter antenna to transmit the pulses of RF energy and form a sensor field;

a receiver antenna to receive RF energy that has reflected off objects in the sensor field;

a receiver pulse generator coupled to the transmitter pulse generator to generate receiver pulses at a receiver pulse rate and with a receiver pulse width;

a receiver delay line between the receiver pulse generator and the transmitter pulse generator to delay the receiver pulses with respect to the transmitter pulses; and

a receiver sampler coupled to the receiver antenna and the receiver pulse generator to sample the RF energy received by the receiver antenna during the receiver pulses.

29. A method of determining a characteristic of an object, comprising:

transmitting bursts of RF pulses at a burst rate and with a burst width that is 5% or less of a time between bursts to form a sensor field;

receiving reflections of the RF pulses off objects in the sensor field; and

evaluating the reflections to determine one or more characteristics of objects in the sensor field.