What Technology is Best for Indoor Wayfinding
The University of Michigan defines wayfinding as “spatial problem solving. It is knowing where you are in a building or an environment, knowing where your desired location is, and knowing how to get there from your present location. Wayfinding is a term used not only for technology, also design of architecture, lighting and static signage all contribute to how people find their way around an area. However many organizations are adopting for digital tools, such as kiosks, tablets or mobile apps, to improve the experience for visitors and staff alike. More venues such as shopping malls, airports, metro stations, hospitals, hotels & resorts, stadiums and entertainment enable indoor navigation technology in addition to Guest Wi-Fi & Experience platform to improve guest experience and enhance digital engagement. Digital wayfinding technology helps visitors to find their way faster, which has an impact on overall business (e.g.: timely attendance to appointments, meetings and flight) and also helps to avoid ask staff for directions. Usually venues display this information on a digital touchscreen kiosk or a tablet at reception / information desk. However due to COVID-19 and safety measures, devices in public venues are not being preferred. Mobile App plays a great role to deliver turn-by-turn navigation with blue-dot experience, similar to what Google Map and Apple Map provides for outdoors. Mobile Wayfinding falls under a broad term call Indoor Positioning, which has two main applications
- Indoor Wayfinding – using digital device such as smart mobile phone to find directions in a building where GPS signal does not work
- Asset and People Tracking in buildings using Indoor IOT Services such as Bluetooth Low Energy (BLE) Tags or Wi-Fi tags
This blog text refers to Indoor Mobile Wayfinding (also called Turn-by-turn Navigation, Indoor Navigation or Indoor GPS). Using a smart mobile phone, visitors can find their way with a Mobile App or Browser App in a building. Indoor Navigation is a need for modern buildings, hospitals, airports, hotels & resorts. Venue operators usually embed a piece of software (Indoor Positioning SDK) within their App to provide this service to their guests and employees
Commonly two technologies are used for Indoor Positioning; Wi-Fi and BLE Beacons. However, there is a third alternative called geomagnetic field, thanks to the enhanced mobile device technologies which is explained below. However, no technology is perfectly solving the indoor positioning needs. All of them have advantages and disadvantages over others
How Indoor Positioning Works?
Indoor positioning algorithms are deployed in two ways;
Server-side Positioning – all data from mobile device is sent to server, and server calculates the position which is shared back with the client mobile device to locate blue-dot on the map
Client-side Positioning – positioning algorithms are deployed at the Mobile App. Advantage of this method is that there is less communicated with the server, which might be slightly faster than server-side positioning
Smartphones have many sensors and antennas built-in such as GPS, Wi-Fi, Bluetooth, magnetic sensor (compass) and barometric sensor. For outdoor environments, GPS sensors are used, such as Google Map. In order to find the location, the phone needs to get signal from 3 satellites to be able to locate a smart device on map. However, GPS can’t be used for indoors because there will be weak or no GPS signal in buildings. Therefor position finding requires indoor equipment such as WiFi, BLE Beacon or earth’s magnetic fields
Indoor Positioning using Wi-Fi
Wi-Fi triangulation is one of the oldest technologies used for this purpose. Reason behind is that all public buildings have Wi-Fi, and vendors tried to utilize this technology. Moreover, all mobile devices have Wi-Fi chip. A zone level positioning can be achieved using Wi-Fi under good circumstances, with a good Wi-Fi triangulation design. However, achieving high precision is not easy, requires hefty investment on Wi-Fi infrastructure.
Wi-Fi is being is not directly used as a single source by IPERA for indoor positioning, however it complements the geo-magnetic field (earth’s magnetic field) indoor positioning algorithm that IPERA and its ecosystem partners are developing. Wi-Fi helps to detect floors as well as indoor / outdoor transition. Any wi-fi network can supported in this regard as long as it communicates with smart phones
Indoor Positioning using Bluetooth Low Energy (BLE) Beacons
BLE Beacons are being installed at many commercial venues. They provide cost-efficient way to create small to midsize indoor positioning deployments for both iOS and Android. However, beacons have their own issues when it comes to accuracy and scalability. Especially battery powered BLE Beacons may require regular maintenance and battery replacement every year or so, depending on usage. Majority of small and medium Indoor Wayfinding vendors are relying on BLE Beacons. The convergence of BLE and Wi-Fi antennas on Wireless Access points is a good option when Access Points built-in BLE Beacons are used for Indoor Navigation purpose.
Indoor Positioning with Geomagnetic Fields
Fast development of sensors technology that is embedded in modern smart phones enabled new opportunities for companies like IPERA and its technology partners to utilize earth’s magnetic field for Indoor Positioning and Mobile Wayfinding. The Earth’s magnetic field strength was measured by Carl Friedrich Gauss in 1832 and has been repeatedly measured since then. Magnetic-field anomalies inside buildings have an impact on compass sensor readings on smart devices. Compass sensor shares the information with the software, and the software knows more about the magnetic field characteristics for that specific building. The more information the software collects, better it gets familiar with the location, and accuracy or precision gets better. According to a recent study, location accuracy can go over 97%, meaning achieving 1-3 meters of accuracy is not a big challenge with a good algorithm. For the same level of location precision, it will require many BLE Beacons to be deployed. However changing floors in a building may not be detected perfectly using this method. Although barometric sensor help to find the vertical movement and change of floors, it might mislead. In this case two simple methods can be applied; 1) placing one battery powered BLE Beacons near each lift to detect floor. 2) or else informing users to change floors when around the lift areas, giving a degree of initiative to visitors and guests, and making it easy for them from user experience perspective to change floor with a single click
In conclusion, no technology is perfect. BLE is the most used technology for Indoor Wayfinding due to its popularity and cost effectiveness. Although battery powered beacons are cost effective and easy to install, some customers may find it difficult to change battery (or beacon itself) every 2-3 years. Utilizing earth’s magnetic field with aid of existing Wi-Fi infrastructure or BLE beacons in a building provides cost effective, yet easy to maintain outcome for venues