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Unmet mobility needs

During October/November 2010, SIRI and the University of Toronto organized user research with visually impaired individuals who were using some form of GPS-based navigation devices besides their cane and/or guide dog, to gather their experiences and views about unmet mobility needs in pedestrian situations. A brief report of the research results and SIRI’s development plans based on them are given below.

A framework to define unmet mobility needs

Pedestrian mobility primarily requires three types of information:

  • Locational: where am I?
  • Informational: what points of interest are around me?
  • Directional: how do I get to where I want to go?

People with visual impairments gauge such information primarily using their auditory and/or tactile senses. Traditionally, white canes and/or guide dogs support them in their pedestrian journeys. GPS-based navigation devices such as the Trekker, designed specifically for vision-impaired users, have proved to be of much help in facilitating independent outdoor navigation. Such devices, however, are usually rather expensive. Mobile phones equipped with GPS-receiver and navigation software have, in recent times, proved to be a boon to pedestrians with vision impairments in boosting their confidence and making independent travel easier for them.

With a view to understanding the contexts in which GPS-based mobility aids might assist navigation for pedestrians with vision impairments, two focus groups were conducted at the University of Toronto in October/November 2010 with visually impaired individuals who used some form of electronic navigation aids besides their cane and/or guide dog. Thirteen persons with vision impairments (11 totally blind and 2 partially sighted) with ages ranging from 23 to 58 participated. Five of them were female and eight male. Six of them used white canes and seven used dog guides (some of them carried a cane as backup.) Six of them used iPhones, six used Nokia phones and one Samsung. Three of them also used a dedicated navigation device called the Trekker.

Upon analysis of the data collected through the focus groups, People, Environment and Technology (PET) emerged as the dimensions defining mobility concerns and needs in the context of the use of electronic navigation aids. Within this PET framework for defining unmet mobility needs, an individual’s mobility is determined by their personal abilities and preferences, the nature of the environment they navigate and the capabilities built into the technology they use. The concerns expressed by the focus group participants relating to their pedestrian navigation experiences are summarized below under three groups – environment-related, technology-related and personal, followed by a summary of their needs in this regard.


Environment-related concerns expressed by the research participants pertain to

  • navigating inside unfamiliar indoor spaces such as subway stations, building, malls, etc.
  • negotiating open (unmapped) areas like parks and parking lots.
  • identifying construction sites and rerouting in real time.
  • maintaining a straight-line course on sidewalks and open spaces.
  • crossing streets, under a variety of conditions.
  • finding bus stops, etc.

Technology-related concerns relate to

  • precision of the location information based on GPS coordinates not being in the range required by (visually impaired) pedestrians, the accuracy sometimes being enough to find the building but not the door.
  • GPS-based navigation systems not working in indoor environments.
  • obstruction to the GPS signals caused by transformers, tall buildings, atmospheric conditions, etc. causing disruptions in the information inputs, etc.
  • most available technologies not being built with needs of visually impaired users in mind.

Participants’ personal concerns are about

  • unaffordable costs of GPS-based navigation devices that are designed specially for the visually impaired.
  • difficulty in operating devices with one hand dedicated to a cane or guide dog.
  • losing ambient (echo) information with earphones that fit into the ear canal.
  • difficulty in learning and operating a smart phone’s complex system.
  • difficulty in controlling the verbosity / volume of the narration on the move.
  • unaffordable data access costs of mobile phone-based GPS navigation systems.
  • cumbersomeness of some dedicated navigation devices that come with several components (handset, external GPS module, headset and compass); awkwardness in operating them.


Some of the needs articulated by the participants are:

  • To be able to adjust the verbosity/ volume of the narration while moving.
  • To be able to learn and operate the system easily.
  • To know real-time information such as traffic conditions and transportation schedules.
  • To not have the system become obsolete quickly and often, given the frequent developments in technology.
  • To know the direction one is facing or walking along at any time.
  • To know information within a reasonable accuracy range (at least knowing which side of the street one is on).
  • To hold a portable, compact single unit rather than a combination of multiple external units.
  • To have a well-secured device that could be used hands-free for personal safety and for protecting the expensive device.
  • To be able to afford buying and using/maintaining the system.
  • To have adequate battery power in the devices.
  • To be able to input one’s own points of interest  (note: already available in some models).

SIRI’s development plans

Guided by the needs expressed by the research participants as above, SIRI has reformulated its development plans for building Privateye as a comprehensive mobility system based on a GPS-enabled mobile phone platform that provides hands-free, voice-controlled mobility, indoor navigation capability and greater location accuracy. In partnership with the Inclusive Design Research Centre (IDRC) and the OCAD University, SIRI will be continuing its work of designing a special headset and supporting research on an accessible indoor navigation system based on Wifi signals.

Given the unusually rapid turnover in smart phones and the impossibility of developing a Privateye app that will work on every platform, perhaps the most vital issue facing SIRI is the degree to which they can or should produce Privateye Apps for any particular handset.   SIRI is countering this challenge by designing a server-based approach called Privateye 3.0 that will accommodate all basic mobile phones equipped with Bluetooth and Wifi. With its superior processing capacity and real time data transmission, the Privateye 3.0 server can offer hands-free voice command operation by adapting many off-the shelf programs.

SIRI’s development efforts are augmented by a development committee that includes experts in the use of a variety of accessible navigation devices who will monitor progress on the development of Privateye 3.0.

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