Door and window contact systems and methods that include MEMS accelerometers and MEMS magnetometers

• US 9,953,503 B2
• Filed: 02/23/2016
• Issued: 04/24/2018
• Est. Priority Date: 02/23/2016
• Status: Active Grant

• Current Assignee: Ademco Inc. (Resideo Technologies, Inc.)
• Original Assignee: Honeywell International Inc.
• Inventors: Smith, Richard Alan
• Primary Examiner(s): Bugg, George
• Assistant Examiner(s): Dorsey, Renee
• Application Number:
  US15/050,855
• Publication Number:
  US 20170243456A1
• Time in Patent Office: 791 Days
• Field of Search: None
• CPC Class Codes: G08B 13/02 Mechanical actuation
• 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 13/2494 by interference with electro-magnetic field distribution combined with other electrical sensor means, e.g. microwave detectors combined with other sensor means

Abstract

Systems and methods that address the gap, security, and robustness limitations of known door and window contact systems and methods without increasing the overall cost thereof are provided. Some systems can include an accelerometer and a magnetometer for mounting in or on a first portion of a window or door unit and a microcontroller unit in communication with each of the accelerometer and the magnetometer. The accelerometer can measure acceleration or vibration relative to a second portion of the window or door unit and transmit the measured acceleration or vibration to the microcontroller unit, the magnetometer can measure magnetic field relative to a sensor magnet mounted on or embedded in the second portion of the window or door unit and transmit the measured magnetic field to the microcontroller unit, and the microcontroller unit can use the measured acceleration or vibration and the measured magnetic field to make a security determination.

Claims

1. A system comprising:

an accelerometer;

a magnetometer; and

a microcontroller unit in communication with each of the accelerometer and the magnetometer;

a housing containing the accelerometer, the magnetometer, and the microcontroller unit; and

a sensor magnet coupled to a surface in a displaced relationship with the housing,

wherein the accelerometer measures a current acceleration or vibration value for the housing relative to the surface and transmits the current acceleration or vibration value to the microcontroller unit,

wherein the magnetometer measures a current magnetic field value relative to the sensor magnet and transmits the current magnetic field value to the microcontroller unit,

wherein the microcontroller unit includes an installation mode,

wherein the microcontroller unit learns a first boundary magnetic field value and a first boundary acceleration or vibration value corresponding to a state of the displaced relationship being open from a combination of a first movement of the housing or the surface and a first user input when the microcontroller unit is in the installation mode,

wherein the microcontroller unit learns a second boundary magnetic field value and a second boundary acceleration or vibration value corresponding to the state of the displaced relationship being closed from a combination of a second movement of the housing or the surface and a second user input when the microcontroller unit is in the installation mode, and

wherein the microcontroller unit uses the current acceleration or vibration value, the current magnetic field value, the first boundary magnetic field value, the first boundary acceleration or vibration value, the second boundary magnetic field value, and the second boundary acceleration or vibration value to make a security determination.

2. The system of claim 1 wherein the housing moves relative to the surface.

3. The system of claim 1 wherein the surface moves relative to the housing.

4. The system of claim 1 wherein the security determination includes the microcontroller unit determining whether the state of the displaced relationship is open, closed, or partially open or closed or the microcontroller unit identifying an attempt to defeat event.

5. The system of claim 4 wherein the microcontroller unit compares at least one of the current acceleration or vibration value and the current magnetic field value to at least one of the first boundary magnetic field value, the first boundary acceleration or vibration value, the second boundary magnetic field value, or the second boundary acceleration or vibration value to determine whether the state of the displaced relationship is open, closed, or partially open or closed or whether the attempt to defeat event is occurring.

6. The system of claim 1 further comprising:

a user input mechanism in communication with the microcontroller unit,

wherein the user input mechanism receives the first user input, the second user input, and a third user input,

wherein the user input mechanism transmits the first user input, the second user input, and the third user input to the microcontroller unit, and

wherein the microcontroller unit uses the third user input to make the security determination.

7. The system of claim 6 wherein the microcontroller unit identifies a signal analysis algorithm to execute in making the security determination based on the third user input.

8. A method comprising:

coupling a sensor magnet to a surface;

mounting a housing containing an accelerometer, a magnetometer, and a microcontroller unit in a displaced relationship with the surface;

the microcontroller unit learning a first boundary magnetic field value and a first boundary acceleration or vibration value corresponding to a state of the displaced relationship being open from a combination of a first movement of the housing or the surface and a first user input when the microcontroller unit is in an installation mode;

the microcontroller unit learning a second boundary magnetic field value and a second boundary acceleration or vibration value corresponding to the state of the displaced relationship being closed from a combination of a second movement of the housing or the surface and a second user input when the microcontroller unit is in the installation mode;

the accelerometer measuring a current acceleration or vibration value for the housing relative to the surface and transmitting the current acceleration or vibration value to the microcontroller unit;

the magnetometer measuring a current magnetic field value relative to the sensor magnet and transmitting the current magnetic field value to the microcontroller unit; and

the microcontroller unit making a security determination using the current acceleration or vibration value, the current magnetic field value, the first boundary magnetic field value, the first boundary acceleration or vibration value, the second boundary magnetic field value, and the second boundary acceleration or vibration value.

9. The method of claim 8 wherein making the security determination includes the microcontroller unit determining whether the state of the displaced relationship is open, closed, or partially open or closed or the microcontroller unit identifying an attempt to defeat event.

10. The method of claim 9 further comprising the microcontroller unit comparing at least one of the current acceleration or vibration value and the current magnetic field value to at least one of the first boundary magnetic field value, the first boundary acceleration or vibration value, the second boundary magnetic field value, or the second boundary acceleration or vibration value to determine whether the state of the displaced relationship is open, closed, or partially open or closed or whether the attempt to defeat event is occurring.

11. The method of claim 8 further comprising:

a user input mechanism receiving the first user input, the second user input, and a third user input;

the user input mechanism transmitting the first user input, the second user input, and the third user input to the microcontroller unit; and

the microcontroller unit using the third user input to make the security determination.

12. The method of claim 11 further comprising the microcontroller unit identifying a signal analysis algorithm to execute in making the security determination based on the third user input.