How automatic doors know when to open
How do these doors know to open when you approach?
There’s nothing more welcoming than a door opening for you. Without the need to be touched to open or close, automatic doors are essential in improving disabled access to buildings, facilitating hygiene in required areas and helping provide general convenience to commercial buildings.
Self-sliding doors began to emerge as a commercial product in 1960 after being invented six years previously by Americans Dee Horton and Lew Hewitt. They started out as a novelty feature, but as their use has grown their benefits have extended within our technologically advanced world. Particularly useful in busy locations or during times of emergency, the doors act as crowd management by reducing the obstacles put in peoples’ way. They give us one less thing to tackle during daily life and the occasional quick escape.
As well as making access both in and out of buildings easier for people, the difference in the way many of these doors open helps reduce the total area occupied by them. Automatic doors often open to the side, with the panels sliding across one another. Replacing swing doors, these allow smaller buildings to maximise the usable space inside without the need to clear the way for a large, protruding door.
There are many different types of automatic door, with each relying on specific signals to tell them when to open. Although these methods differ, the main principles remain the same. Each automatic door system analyses the light, sound, weight or movement in their vicinity as a signal to open. Sensor types are chosen to complement the different environments they are needed in. For example, a busy street might not suit a motion-sensored door, as it would constantly be opening for passers-by. A pressure-sensitive mat would be more appropriate to limit the surveyed area.