METHOD FOR ROBUST AND FAST PRESENCE DETECTION WITH A SENSOR

摘要

A method is presented for detecting the presence of objects. The method differentiates animate objects within a presence detector detection area from inanimate objects within the detection area. Moving objects passing nearby the detection area are further distinguished from objects entering or leaving the detection area. The method distinguishes inanimate objects from dormant animate objects within the detection areas.

主权项

1. A method for detecting the presence of animate/inanimate objects with a sensor configured to transmit a signal and receive a signal reflection within a detection area comprising a first zone and a second zone, the first zone comprising an area within a first distance from the sensor, the second zone comprising an area beyond the first zone and within a second distance from the sensor, wherein the second distance is greater than the first distance, the method comprising the steps of:
detecting an object with the sensor; determining if the object is in the first or second zone of the detection area; if the object is within the detection area, characterizing the object as one of the group consisting of animate objects, and inanimate objects; if the object is within the detection area and is characterized as inanimate, declaring the object not present; if the object is within the detection area and is characterized as animate, declaring the object present; and
wherein the step of determining if the object is in the detection area includes measuring a time of flight variance between the signal transmission(s) and the signal reflection(s) and using a near object variance threshold when the object is in the first zone and a distant object variance threshold when the object is in the second zone.