How Accessible Audio Navigation Works
Indoor Audio Wayfinding and Audio Navigation
Interior spaces are often complex, highly flexible and ever-changing environments. People often find it difficult to navigate large spaces such as hospitals, shopping centres or transport hubs to find specific locations or objects within these environments. Static signage and maps are often inadequate for navigation. This is especially true for people with vision loss, who face significant limitations obtaining information from traditional sources such as overhead signs, information screens and colour-coded direction indicators.
Indoor navigation systems are a rapidly emerging service aiming to help people navigate complex indoor spaces. Deloitte estimates that by 2022, 25% of uses of a navigation application will include an indoor element as these systems become widely available and consumers get used to their benefits. Indoor navigation systems have great potential to improve accessibility for a variety of groups by providing augmented reality wayfinding guidance. In the UK, the Design of an accessible and inclusive built environment standard (BSI 8300) recognises audio navigation as a wayfinding method to improve accessibility.
The Wayfindr Open Standard
The Wayfindr Open Standard contains guidance on the design of an accessible indoor audio navigation system to ensure it is usable by people who are blind or vision impaired. In particular, the Open Standard contains guidance on environmental features, mobile application features, and the use of Bluetooth Low Energy (BLE) beacons for indoor positioning and navigation (although the use of other technologies is possible). The Open Standard is recognised by the International Telecommunication Union as ITU-T F.921.
Later in 2018, we will be launching a training course on accessible audio navigation, aimed at those working in the field of building accessibility or designing navigation apps.
The Importance of Standardised Information for Audio Navigation Systems
For audio navigation systems to be used by blind or vision impaired people, users need a guaranteed consistent and high quality experience. This is crucial so that users know what experience an audio navigation system is going to provide and how it will function as a complementary mobility aid to a primary mobility aid (e.g. a long cane or a guide dog). This guaranteed consistent and high quality experience is provided by use of the Wayfindr Open Standard for Accessible Audio Navigation.
For more information on the role of standards in audio navigation you can read this White Paper from G3ICT, the International Advocacy Initiative for Digital Inclusion of Persons with Disabilities.Audio Navigation White Paper
The Building Blocks of an Indoor Audio Navigation System
An indoor navigation system requires several key elements to function properly and to deliver navigation information to end users. When combined correctly, indoor maps, indoor positioning technologies, and mobile applications can empower vision impaired users to travel independently through complex environments like train stations, hospitals, and shopping centres.
Indoor navigation systems require a highly-accurate map of the environment in which the system is to operate, including information on environmental features such as escalators or lifts, as well as changes in floor surfaces and elevation. Mapping and navigation platforms are available which allow for the dynamic updating of content.
Section 1.10 of the Wayfindr Open Standard provides information on specific features, landmarks, and objects for which audio guidance should be given. These features, landmarks, and objects should be included in any map that is to be used as the basis for and indoor navigation system.
Indoor Positioning Technology
Indoor navigation solutions, in order to be effective and reliable, need to rely on extremely accurate positioning systems, which, combined with various forms of indoor mapping, provide necessary data to generate accurate audio directions to the user. While very sensitive GPS devices can receive satellite signals indoor, those are not received with the precision required for accurate indoor positioning.
Various technologies have been used to provide accurate positioning, including a combination of indoor markers that can be mapped and mathematical models that calculate position and path finding directions, and in some cases, combine information from various sources.
There are several different approaches to mapping indoor venues – ranging from use of communications technologies like Wi-Fi and Bluetooth, (sometimes referred to as radio fingerprinting), to LED lighting and inertial sensor navigation (sometimes referred to as dead reckoning). Even magnetic field variations can be used.
To improve accuracy, indoor positioning may rely on various data sources including optical or acoustic and ultrasonic technologies, or the positions of emitters of radio signals to determine the in-door position of a user or the use of fixed QR coding markers. Besides radio beacons using low energy Bluetooth beacons, alternative promising methods use signals of existing Wi-Fi access points. This is an appealing option since Wi-Fi networks can be found in most indoor environments. It is also possible that 5G small cell networks points of presence may be used for similar purposes. Finally, Radio Frequency Identification systems are also used for indoor navigation as passive beacons to confirm a location or presence of an object.
Section 2.11 of the Wayfindr Open Standard gives information on the use of Bluetooth Low Energy Beacons for Indoor Navigation.
Indoor Navigation Applications
Indoor navigation services are most often delivered to end users through mobile applications, which can either be navigation-dedicated apps or venue-specific apps which may also provide other services.
Venue owners also have the option of providing an application programming interface (API) which allows application providers to import the data needed to provide indoor navigation services into their applications.
As of today, commercially available audio indoor navigation systems offer four different types of user support and guidance, sometimes combined:
- providing positioning information (where am I?)
- providing information on surroundings (what’s around me?)
- providing point of interest information (details as to what’s in front of me such as an exhibit or explanation of a building feature or function)
- providing “point A to point B” step by step navigation directions.
Section 1.12 of the Wayfindr Open Standard gives information on the functions of a mobile application for an accessible indoor navigation system.
The are many indoor navigation application providers in the Wayfindr Community who can provide ready-made indoor navigation solutions for your estate.
Audio Navigation in Action
Check out this video of audio navigation being used to guide a completely blind user through an unfamiliar environment and imagine how audio navigation could make your venue accessible to so many more people