A Prototype Audio-Tactile Map System with an Advanced Auditory Display

Navigational Aids For The Visually Impaired

It is common for blind people to explore a new location (such as a work environment) when there is little other traffic present, in an effort to develop a mental map of the location; the spatial model developed from gathering this experiential knowledge is a cognitive map (Kuipers, 1978). From the outset, it was the intention of the ATM project to address this type of scenario by providing a virtual reality tool which can help a visually impaired individual to form a cognitive map of a location remotely, before visiting the physical site (Picinali et al., 2014a). Assistive navigational technology for blind and visually impaired individuals takes a number of approaches, but may be broadly classified into in-navigation or pre-navigation tools, the latter of these being of primary concern here. The reader is directed to literature reviews included in documentation of the background experimental work for the present project (Picinali et al., 2014a) and early-stage documentation of the ATM project (O’Sullivan et al., 2014a, O’Sullivan et al., 2014b).

Mobile devices equipped with Global Positioning System (GPS) technology allow visually impaired travellers to receive direction while in transit via an auditory and/or a tactile display. In the case of the former, Rowell & Ungar (2003) found that synthesised verbal delivery can be distracting at times, but a comprehensive review of the effectiveness of in-navigation systems in outdoor environments was positive (Loomis, 2001). The Blind Maps system is a concept providing an assisting-device with real-time tactile feedback only, i.e. no audio (Spitz et al., 2012). It was designed as a portable clip-on peripheral for the Apple iPhone for use with on-line map applications. The device renders symbols on an actuated pin display to direct the user during a journey, allowing aural focus to be kept on surroundings. An example of a navigational tool that is currently active is Open Street Map for the Blind (OSMB), as described in Rifat et al. (2011) and with information available online¹. This is an open-source, user-maintained map system which is audio-based and delivered via mobile phones equipped with screen readers. OSMB is a well-considered list of established world features and associated audio tags that aid mapping and system development by the contributors. More generally, design guidelines for assistive devices for blind pedestrians that aim to help spatial cognition have been suggested by Gallay et al. (2013).