A discreet detection unit with an infra red motion detector remote from the bed. The alarm is raised as soon as the users foot descends to the floor. The same sensor can be positioned to detect them sitting up, leaving a room, or entering a hazardous area. It can also detect door usage, where a door may be left open. It replaces door and floor mats which can be a trip hazard.
The battery operated motion sensor has a perfect detection beam for sensing the legs of someone leaving their bed without triggering if they simply sit up in bed. By being positioned across the room there is no bedside mat to be avoided or tripped over and nothing to destroy. The alarm is also raised before any weight is placed on the feet. Positioned a bit higher it can detect someone sitting up in readiness to leave their bed.
Another popular use is mounted above a door way looking down. In this case the door can be left open and the alarm is raised if the occupant crosses the threshold.