MEMS based garage door sensor

A garage door intrusion sensor for a security system comprising a garage door and a MEMS (micro-electro-mechanical system) sensor attached to the garage door to determine the orientation of the garage door with respect to the earth, wherein an orientation of the overhead garage door parallel to the earth is indicative of an open garage door and an alarm condition, and an orientation of the overhead garage door orthogonal to the earth is indicative of a closed garage door and a restore condition, wherein the MEMS sensor is a MEMS accelerometer mounted with a sensitive axis of the MEMS accelerometer, along which the MEMS accelerometer measures acceleration/gravity, pointing vertically downward towards the earth when the overhead garage door is closed, such that the MEMS accelerometer measures a 1 g acceleration/gravity force, and when the overhead garage door is open, the sensitive axis of the MEMS accelerometer points horizontally with respect to the earth, such that the MEMS accelerometer measures a 0 g acceleration/gravity force, such that the output of the MEMS accelerometer, indicating either a 1 g or a 0 g measured acceleration/gravity force, indicates whether the overhead garage door is respectively closed or open.

A garage door intrusion sensor for a security system comprising a garage door and a MEMS (micro-electro-mechanical system) sensor attached to the garage door to determine the orientation of the garage door with respect to the earth, wherein an orientation of the overhead garage door parallel to the earth is indicative of an open garage door and an alarm condition, and an orientation of the overhead garage door orthogonal to the earth is indicative of a closed garage door and a restore condition, wherein the MEMS sensor is a MEMS accelerometer mounted with a sensitive axis of the MEMS accelerometer, along which the MEMS accelerometer measures acceleration/gravity, pointing horizontally with respect to the earth, such that when the overhead garage door is closed the MEMS accelerometer measures a 0 g acceleration/gravity force, and when the overhead garage door is open, the sensitive axis of the MEMS accelerometer points vertically downwards with respect to the earth, such that the MEMS accelerometer measures a 1 g acceleration/gravity force, such that the output of the MEMS accelerometer, indicating either a 0 g or a 1 g measured acceleration/gravity force, indicates whether the overhead garage door is respectively closed or open.