Method and apparatus for detection of motion with a gravitational field detector in a security system

• US 6,724,316 B2
• Filed: 10/29/2002
• Issued: 04/20/2004
• Est. Priority Date: 10/16/2001
• Status: Expired due to Term

• Current Assignee: Ademco Inc. (Resideo Technologies, Inc.)
• Original Assignee: Honeywell International Inc.
• Inventors: Eskildsen, Kenneth G., Addy, Kenneth L.
• Primary Examiner(s): Wu, Daniel J.
• Assistant Examiner(s): Nguyen, Tai T.
• Application Number:
  US10/282,663
• Publication Number:
  US 20030071739A1
• Time in Patent Office: 539 Days
• Field of Search: 340/686.1, 340/545.1, 340/545.6, 340/545.9, 340/547, 340/539.1, 340/693.3, 340/571, 340/551, 340/552
• US Class Current: 340/686.1
• CPC Class Codes: G08B 13/08 by opening, e.g. of door, of window, of drawer, of shutter, of curtain, of blind
• CPC Class Codes: G08B 13/2491 Intrusion detection systems, i.e. where the body of an intruder causes the interference with the electromagnetic field

Abstract

In a first aspect, the present invention is a method, apparatus, and system for detecting a change in position of a door or a window in an alarm system with a singular housing having a magnetometer for monitoring the magnetic field of the earth, and a microprocessor for detecting a change in the position of the singular housing with respect to the magnetic field of the earth. The microprocessor generates an alarm signal upon detecting the change, and causes the alarm signal to be transmitted, by wireless transmission, to a remote receiving station. The device may also be used to determine if an object that it is affixed to has been moved, such as for a theft alarm for an object such as a painting. In a second aspect of the invention, a gravitational sensor is used to monitor the gravitational field of the earth and determine if an associated object or person has been moved with respect to the gravitational field, thus providing motion detection and signaling an alarm.

Claims

1. A method of generating an alarm signal upon detecting a change in position of an object comprising the steps of:

a) locating a housing with respect to the object;

b) monitoring, with apparatus in the housing, the gravitational field of the earth;

c) detecting, with apparatus in the housing, a change in the position of the housing with respect to the gravitational field of the earth;

d) generating an alarm signal upon detecting a change in position of the housing with respect to the gravitational field of the earth that exceeds a first predetermined threshold; and

e) transmitting by wireless transmission the alarm signal to a remote receiving station.

2. The method of claim 1 wherein the housing is located with respect to the object by affixing the housing to the object.

3. The method of claim 1 wherein the housing is located with respect to the object by hanging the housing from the object.

4. The method of claim 1 wherein said apparatus in the housing comprises:

a) a gravitational sensor that detects the earth'"'"'s gravitational field and generates an output signal, wherein the output signal is correlated to the earth'"'"'s gravitational field;

b) processing means for detecting a change in the output signal from the gravitational sensor, and for generating an alarm signal when the change is greater than the first predetermined threshold; and

c) an RF transmitter for transmitting the alarm signal.

5. The method of claim 4 wherein said detecting step comprises the steps of:

i. determining a static output signal from the gravitational sensor;

ii. storing the static output signal from the gravitational sensor; and

iii. sampling the output signal from the gravitational sensor at a predetermined time interval.

6. The method of claim 5 wherein said detecting step further comprises the steps of:

iv. subtracting the sampled output from the gravitational sensor from the stored static output of the gravitational sensor to produce a difference value; and

v. determining if the absolute value of the difference value is greater than the first predetermined value.

7. The method of claim 1 wherein said step of detecting a change in the position of the housing with respect to the gravitational field of the earth takes place on two axes.

8. The method of claim 7 wherein said step of generating an alarm signal occurs upon detecting a change in position of the housing in one of the two axes.

9. The method of claim 1 further comprising the step of generating a trouble signal upon detecting a change in position of the housing with respect to the gravitational field of the earth that exceeds a second predetermined threshold.

10. The method of claim 9 wherein the second predetermined threshold is less than the first predetermined threshold.

11. An apparatus for generating an alarm signal upon detecting a change in position of a housing comprising:

a) means for monitoring the gravitational field of the earth;

b) means for detecting a change in the position of the housing with respect to the gravitational field of the earth;

c) means for generating an alarm signal upon detecting a change in position of the housing with respect to the gravitational field of the earth that exceeds a first predetermined threshold; and

d) means for transmitting by wireless transmission the alarm signal to a remote receiving station.

12. The apparatus of claim 11 wherein said means for monitoring the gravitational field of the earth comprises:

i. a gravitational sensor that detects the earth'"'"'s gravitational field and generates an output signal, wherein the output signal is correlated to the earth'"'"'s gravitational field; and

ii. processor means for sampling the output signal and evaluating it.

13. The apparatus of claim 12 wherein said means for detecting a change in the position of the housing with respect to the gravitational field of the earth comprises:

i. means for determining a static output signal from the gravitational sensor;

ii. means for storing the static output signal from the gravitational sensor; and

iii. means for sampling the output signal from the gravitational sensor at a predetermined time interval.

14. The apparatus of claim 13 wherein said means for detecting a change in the position of the housing with respect to the gravitational field of the earth comprises:

iv. means for subtracting the sampled output from the gravitational sensor from the stored static output of the gravitational sensor to produce a difference value; and

v. means for determining if the absolute value of the difference value is greater than the first predetermined value.

15. The apparatus of claim 11 wherein the means for detecting of change in the position of the housing with respect to the gravitational field of the earth detects said change on two axes.

16. The apparatus of claim 15 wherein said means for generating an alarm signal generates an alarm signal upon the detection of a change in position of the apparatus in one of the two axes.

17. The apparatus of claim 11 wherein the alarm signal contains a unique transmitter identification number.

18. A security system comprising:

a) a single-housing motion sensing device comprising;

i. means for monitoring the gravitational field of the earth;

ii. means for detecting a change in the position of the housing with respect to the gravitational field of the earth;

iii. means for generating an alarm signal upon detecting a change in position of the housing with respect to the gravitational field of the earth that exceeds a first predetermined threshold; and

iv. means for transmitting by wireless transmission the alarm signal to a remote receiving station; and

b) a receiving station located remotely from the single-housing motion sensing device comprising;

i. means for receiving by wireless transmission the alarm signal, and

ii. means for indicating an alarm condition in response to receipt of the receipt of the alarm signal.

19. The security system of claim 18 wherein said means for monitoring the gravitational field of the earth comprises:

i. a gravitational sensor that detects the earth'"'"'s gravitational field and generates an output signal, wherein the output signal is correlated to the earth'"'"'s gravitational field; and

ii. processor means for sampling the output signal and evaluating it.

20. The security system of claim 19 wherein said means for detecting a change in the position of the housing with respect to the gravitational field of the earth comprises:

i. means for determining a static output signal from the gravitational sensor;

ii. means for storing the static output signal from the gravitational sensor; and

iii. means for sampling the output signal from the gravitational sensor at a predetermined time interval.

21. The security system of claim 20 wherein said means for detecting a change in the position of the housing with respect to the gravitational field of the earth comprises:

iv. means for subtracting the sampled output from the gravitational sensor from the stored static output of the gravitational sensor to produce a difference value; and

v. means for determining if the absolute value of the difference value is greater than the first predetermined value.