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INDOORS PEOPLE COUNTERS
This page presents examples of visitor counters inside buildings. Generally visitors will be counted both entering and leaving through a doorway. If there is more than one external door then all their counts can be added up and then halved to calculate the total building footfall since every visitor is counted twice somewhere. Sometimes internal doors are also monitored to determine the relative appeal of internal areas like exhibits, a cafe or shop. These buildings often have WiFi where each door or room sensor is linked to a Linetop WiFi gateway located in an office area which forwards live data to the Internet making it accessible via Linetop’s data dasboard to browsers on office PCs or smartphones. Where WiFi is unavailable we can instead send counter data to the Internet over the 4G mobile gateway. Where there no telecoms whatever, or no desire to use them, the counters can instead save data in flash memory in data loggers which are manually downloaded, typically on a seasonal basis. The banner photo above shows an external door that inconveniently swings inwards only. So its break-beam sensor was constructed in the gaps between the glass door and its wooden shutters which has the advantages of being both discreet and secure overnight.
Countryside centres
Forestry, National Parks and Local Authorities often own visitor centres. Counting cars is an obvious proxy for VC footfall, but not everyone arriving at a facility will make use of the VC building while others may use it more than once during any visit - so VC data is often more of an ‘activity index’. Doors that open outwards, as in the photo above, and sliding doors both suit a break-beam sensor placed close by on the inside walls. Sometimes a lobby area between outer and inner sets of doors suit an optical beam. Security is rarely an issue since typical VC buildings are supervised during the day and locked up at night.Unstaffed exhibition or
bird-hide style building
Security is a bigger issue with these, so covertness is often important. When the door opens inwards, as in the photos above, then an optical or body heat sensor built into the door frame externally may be needed. The wiring may be cabled back indoors to be logged or forwarded by telemetry. It will improve accuracy if the door is propped open during business hours so as to make visitor traffic more fluid. But it will still work even if people have to push the door to enter provided that the sensor is close to the door and in the plane of the door so that it does not detect people as they approach.Museum and gallery
Variety amongst external doors is immense so each door needs to be considered a special case. The photo shows a glass-sided semi-circular doorway where the sensor spans the semi-circular part, but not the double doors which unhelpfully swing inwards. Rotating doors are even more of a challenge - clearly a break-beam put where people exit the ‘roundabout’ will work, but we have also used pressure sensor mats within such doorways. Automatic doors are operated with optical sensors (or sometimes radar) and care is needed so that the door and counter sensors do not interfere.
Public libraries and TICs
Book loan data can be useful, but not all library users come to borrow books. They might return them, they might borrow several books at once, read a newspaper, use the Internet, and book loan data might not be amenable to detailed analysis unlike logger data. Libraries and Tourist Information Centres (TICs) are similar to countryside centres when devising visitor counters for their main doors. Automatic doors opening outwards are a real blessing for footfall monitoring since an optical sensor can be positioned inside the building, ideally very close to the door frame which produces very accurate visitor data.Retail and cafe areas
The front door is frequently the main footfall research target, but one might also wish to track visitor movements through specific areas of interest. Till sales data can be useful too, and more so the ‘conversion ratio’ of shop footfall to sales transactions along with the ‘average spend per visitor’ and the trends for both of these derivatives. If the shop is at a countryside visitor centre then clearly the ratio of the car arrivals to shop footfall is a key metric. Multiply cars by 2 to get a passenger estimate. At historic monuments, the shop is often where visitors decide to buy a ticket or not. The shop footfall to ticket sale ratio should be tracked.Public toilets
The usual sensor approach for toilets is a body heat sensor fixed above the main door lintels where the door itself does not swing underneath the sensor. Toilets in the countryside are often of interest to Local Authorities or the organisations which fund them. A survey by one local council found that usage varied from a dozen people per week in a tiny village to thousands in a touristic town near to a railway station and shops. Their aim was to close a third of them and enhance facilities at the remaining sites. The image above shows online 4G telemetry results for a building that a district council was contemplating taking over. The spike coincides with two community events.
VISITOR COUNTERS
