In this section
This section classifies the different types of audio instructions that have been used during Wayfindr indoor trials in places such as Mainline Rail and Metro stations. The analysis of different audio instructions carried out by other researchers [1, 2] has been used as a reference. This classification will continue to evolve as research and further trials are carried out in new environments.
3.1 The classification
The audio instructions can be classified as follows:
- Route starting are instructions that define the starting point for the route as well as the kind of environment that the users are entering. It is important to identify the user’s orientation first so that the audio instructions are aligned with it.
- Route ending are instructions that inform users that they have reached their destination and that the navigation guidance is ending. This instruction can include information about the physical layout of the destination in order to help vision impaired people make better sense of the space and position themselves in relation to other objects such as the exit, a ticket machine, platform edge or bus stop edge. A specific guideline on Route Ending instructions can be found in Section 22.214.171.124.
- Orientation in place for progression to the next environmental feature: These are instructions for direction change that require immediate action from users. They must link to the current environmental clue or landmark: an area, a decision point, a pathway or an object.
At the bottom of the stairs, turn left and walk forward
At the bottom of the stairs, turn left and walk forward to the ticket gates
The instruction above links to the next environmental feature namely the ticket gates.
- Orientation in place for reassurance: These instructions do not require any change in direction but act to reassure users that they are on the right route. Usually they repeat the action from the previous audio instruction to assist positioning in relation to the user’s progression. For example, when there are no landmarks:
Keep walking forward
You are halfway there
If there are landmarks that can be referenced then use them, for example:
Keep walking past the ticket gates on the left
- Orientation prior to reaching and passing an environmental feature: These instructions announce a change in direction prior to reaching an environmental feature. Usually these types of instructions help vision impaired people to prepare for the next move without them having to stop or block the flow of people around them. For example, in environments where tactile walking surface indicators are used to provide guidance:
At the next tactile paving intersection, follow the tactile paving route to the left
Take the first corridor left and walk forward
Once the environmental feature has been negotiated instructions are needed for a change in direction for example:
At the bottom of the stairs, walk forward
At the end of the escalator, turn left and walk to the platform
The instruction above links to the next environmental feature, namely the platform.
- Alerts about location of (next) environmental feature these instructions inform users about the location of specific features in the environment. They are descriptive in nature. Usually, they follow immediately after instructions that orientate users in relation to the next environmental feature. For example:
The down escalator is the left one.
The wide gate is the left one.
The call buttons are between the two lifts.
- Alert when approaching an environmental feature: these instructions advise users that they are approaching the environmental feature that they are aiming for. This type of instruction does not usually require any action but serves more as a warning to users. Normally these alerts are linked to the previous audio instructions that inform vision impaired people about the action required once they reach the environmental feature. For example:
You are approaching the escalators
You are approaching the stairs
- Warning about user’s current location These are instructions that inform users about the spatial layout and their positioning at their current location. They can be given on demand namely when users ask for their current location, their progress along their route and information about what is around them. (NB. This functionality is not currently demonstrated in the Wayfindr Demo iOS app v0.4.)
- Gaunet, F., & Briffault, X. (2005). Exploring the functional specifications of a localized wayfinding verbal aid for blind pedestrians: Simple and structured urban areas. Human-Computer Interaction, 20(3), 267-314. (last accessed: 24 February 2016)
- Passini, R., & Proulx, G. (1988). Wayfinding without vision an experiment with congenitally totally blind people. Environment and Behavior, 20(2), 227-252. (last accessed: 24 February 2016)