An automatic door, also known as an auto door, is a door that opens automatically, usually on sensing the approach of a person.
In the 1st century AD, mathematician Heron of Alexandria in Roman Egypt invented the first known automatic door. He described two different automatic door applications. The first application used heat from a fire lit by the city's temple priest. After a few hours atmospheric pressure built up in a brass vessel causing it to pump water into adjacent containers. These containers acted as weights that – through a series of ropes and pulleys – would open the temple's doors at about the time people were to arrive for prayer. Heron used a similar application to open the gates to the city.
In 1931, engineers Horace H. Raymond and Sheldon S. Roby of the tool and hardware manufacturer Stanley Works designed the first model of an optical device triggering the opening of an automatic door. The invention was patented and installed in Wilcox's Pier Restaurant in West Haven, Connecticut for the benefit of waiters carrying plates of food and drink. The entire system plus installation was sold for $100.
In 1954, Dee Horton and Lew Hewitt invented the first sliding automatic door. The automatic door used a mat actuator. In 1960, they co-founded Horton Automatics Inc and placed the first commercial automatic sliding door on the market.
Peterborough (/ˈpiːtərbərə, -ˌbʌrə/ (About this soundlisten)) is a cathedral city in Cambridgeshire, England, with a population of 202,110 in 2017. Historically part of Northamptonshire, it is 76 miles (122 km) north of London, on the River Nene which flows into the North Sea 30 miles (48 km) to the north-east. The railway station is an important stop on the East Coast Main Line between London and Edinburgh. Peterborough is also the largest city and borough in Cambridgeshire and the East Anglia area of England.
The local topography is flat, and in some places the land lies below sea level, for example in parts of the Fens to the east of Peterborough. Human settlement in the area began before the Bronze Age, as can be seen at the Flag Fen archaeological site to the east of the current city centre, also with evidence of Roman occupation. The Anglo-Saxon period saw the establishment of a monastery, Medeshamstede, which later became Peterborough Cathedral.
The population grew rapidly after the railways arrived in the 19th century, and Peterborough became an industrial centre, particularly known for its brick manufacture. After the Second World War, growth was limited until designation as a New Town in the 1960s. Housing and population are expanding and a £1 billion regeneration of the city centre and immediately surrounding area is under way. Industrial employment has fallen since then, a significant proportion of new jobs being in financial services and distribution.