The Use of Remotely Triggered Talking Sign Systems by Blind and Partially Sighted People
Gill Whitney
Joint Mobility Unit
Royal National Institute for the Blind
London, W1N 6AA
tel: + 44 171 388 1266
fax:+ 44 171 387 7109
email: GWhitney@rnib.org.uk
1. Summary
The aim of this paper is to describe how blind and partially sighted people can be assisted in finding their way round complex public buildings including transport interchanges by the use of remotely triggered talking signs. It describes how the OPEN (Orientation by Electronic Navigation) technology was used, how the users were selected and the results from these trials.
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2. Introduction
In common with the rest of the population blind and partially sighted people like to have the opportunity to visit and use leisure, shopping and other facilities in a safe environment. One of the main problems they will experience is that of knowing what facilities are available and how to get to them. By supplementing the visual signage with remotely triggered talking sign systems blind and partially sighted people will be able to visit shopping complexes, sports centres, transport interchanges, universities and other places independently or with friends and make use of all the facilities offered.
The OPEN remotely triggered talking sign was specified, produced and evaluated for a three year project funded under the European TIDE program.
The system was evaluated during the summer of 1997. 160 blind and partially sighted people were observed using the OPEN infra-red talking sign system. The signs were situated in four different metropolitan train stations in London, Paris and Rotterdam. The talking signs were set up so that the user could find and follow a route within the station or between different areas of the station.
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3. The Objectives of the Trials
The objective of the trials at the four stations was to discover whether the users could use the open system to navigate through the various parts of the different stations. The system had to assist the user to find the features of the station that they needed to complete their journey. It was also investigated whether the system gave them enough information on their location and direction of travel and whether the system helped reduce the stress of travelling.
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4. The Evaluation Sites and Equipment
The aim of the OPEN project was to guide blind and partially sighted travelers through four metropolitan railway stations. The stations selected for the trials were, South Kensington and Heathrow Terminal 4 underground stations in London, Chatelet underground station in Paris and Blaak station in Rotterdam. The four stations were selected so that the system could be evaluated in a range of stations from the small and often empty (Heathrow terminal 4) to the very large and very busy (Chatelet).
The OPEN system consisted of infra-red beacons fixed throughout the station and a receiver carried by the user. A infra-red beam was broadcast continuously from the beacon. When the user approached the beacon a message was transmitted from the beacon to the user device and spoken to the user via a set of headphones or a small speaker. The OPEN beacons were both multi-channel (different language messages could be broadcast at the same time) and networked (messages could be downloaded from a central computer).
The system was designed to give the traveler orientation information through the station so that they could travel successfully between the station entrance and the train they wish to catch, between trains at interchanges and from the train to the exit.
The system operated by giving the user spoken orientation information when they came within range of a beacon. Two types of message were given out by the beacons, the first type of message was used on the direction beacons throughout the station. These messages were written so that they consisted of three pieces of information:
1) Destination - where the sign was given directions to
2) How to get there
3) Any information to confirm directions
A message could have up to three segments with the above structure. Some of the messages also started with a description of the users location .
The following messages used this structure:
For the Piccadilly line turn right and go up the stairs.
For the exit carry straight on, for the district and circle line eastbound turn right, for the district and circle line westbound turn right.
RER Line B, for the exit and routes to all other platforms turn right and go up the stairs.
The second type of message was used on the `next train' announcement beacons on the station platforms. These beacons told the user the name of the station, the name of the line, the direction of the line and the time to the next train.
The beacons were positioned so that the user automatically heard the messages as they walked through the station. The user followed the instructions in the spoken message if it was relevant to their route or carried on to the next beacon if not. If the user missed part of the message they stood still and heard the message again, if the message was unclear the user moved a step or two to get into a better position to hear the message (the message was clearest in the centre of the beam at the edges some `crackle' obscured the words).
The siting of the beacons was carried out with reference to the architectural features of the stations.
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5. Selection of Trial Subjects
The trial subjects were selected with the aim of getting a representative sample of mobile blind and partially travellers who would benefit from the introduction of these systems. This meant that for the trials people who already travelled independently using a single station or a range of stations as well as those who do not currently use stations but who had the mobility skills to use them safely were required. Three groups of people were identified as fulfilling these criteria:
1) Blind and partially sighted people who used familiar and unfamiliar stations. It was hoped that the technology could benefit this group by enabling them to travel more easily and efficiently with less stress.
2) Blind and partially sighted people who used only familiar stations. This group would benefit if a talking sign system enabled them to travel freely within the bus and train systems rather than just use routes they know well.
3) Blind and partially sighted people who did not travel on public transport because of fears of getting lost in stations.
Pre-trial questions were asked of each volunteer subject to place them in one of the above categories. As far as was possible each group was set up to contain male and female travellers of varying ages who used a variety of mobility aids or no aid and who had a variety of sight loses. Each volunteer had to be able to move safely in the station environment.
It is interesting to note that for these trials approximately 70% of the volunteers had had mobility training, this is greatly above the national average in the United Kingdom. In the United Kingdom 5% of the blind and partially sighted population have had long cane training, 1% currently have a guide dog. It is not known what percentage of blind and partially sighted people who would make use of remotely triggered talking sings if they were available have had mobility training.
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6. The Trials
The trials of the OPEN system consisted in a user travelling through the station using the system whilst being followed by an evaluator. A set trial procedure was followed to ensure the safety of the volunteer and to ensure that the maximum amount of information was obtained from the user trials. The rules of the trials were as follows:
1) A trained evaluator accompanied the user at all times, they did not interrupt the user unless the users safety was in question or the user had lost the route and could not find their way back to the previous beacon.
2) The user could ask for assistance or ask to terminate the trial at any point in the trial. In practice no users stopped the trial completely but a number of them asked (and received) assistance in finding the next beacon.
A questionnaire was completed following the trial and observation of the users journey through the station noted.
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7. Results from the Trials
The Trials of the OPEN system finished in September 1997. From this research it was discovered that the majority of the users (91%) felt that the system helped them to locate relevant features of the stations used. This was in spite of some technical problems with the system which caused:
1) the range of the beacons (both length and width) to be less than needed to "catch" the user as they walked past.
2) the volume and quality of the messages to be of insufficient for all the messages to be understood by all the volunteers.
Information was gained from the project on how to write messages for the beacons, the type of voice to use for the recording, where to install the beacons, where the OPEN beacons should be used in conjunction with other systems (such as tactile surfaces), how the users used the system and where they need the system.
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8. Conclusions
The project was able to demonstrate that the OPEN system could be of benefit to a wide cross section of the blind and partially sighted population. The feedback from the users demonstrated that the users can use remotely triggered talking sign systems and want OPEN or a system like it in the stations they use, especially in the stations and other public buildings that they are unfamiliar or semi-familiar with.
To this conclusion two provisions should be added:
1) The signs will be of most benefit if they were used as part of a complete system of environmental adaptations. By the use of tactile guide paths with a number of remotely triggered talking signs, the user could be guided to the best position to receive the message.
2) Where possible training in the use of these systems should be provided as part of the users mobility training. Special consideration needs to be made for the large number of people who have not undergone mobility training.
References:
OPEN Project - User Trials Report, CEC TIDE 1182/OPEN/User Trials Report, November 1997, University of Portsmouth Enterprise Ltd.
Blind and Partially Sighted Adults in Britain: The RNIB Survey, I Bruce, A McKennell and E Walker, 1991, HMSO Publications.
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