Anderson, S. M. – VEMI Lab

Use of an Indoor Navigation System by Sighted and Blind Travelers: Performance Similarities across Visual Status and Age

eblackwood — Mon, 24 Aug 2020 20:22:57 +0000

This article first reviews the pros and cons of current accessible indoor navigation systems and then describes a study using commercial smart devices to navigate routes through a complex building. Our interest was in comparing performance when using real-time narrative descriptions (system-aided condition) vs. a memory- based condition where the same narrative information was only provided to users from the route’s origin. We tested two groups of blind and visually impaired (BVI) users, including people above and below 60 years of age, as well as a third sighted control group. Evaluating older BVI participants is important, as the major- ity of vision loss is age-related, yet navigation performance using access technology is rarely studied with this demographic. Behavioral results demonstrated that access to real-time (system-aided) information led to better navigation accuracy and greater confidence by blind users compared to the information-matched mem- ory condition. Performance for blind participants over 60 years old was nearly identical with their younger peers—an important outcome supporting the efficacy of using navigational technologies by this fast-growing population. Route completion accuracy and requests for assistance did not reliably differ between blind and sighted participants when using the system, suggesting that access to narrative route information led to functionally equivalent navigation behavior, irrespective of visual status. Survey results revealed strong user support for real-time information and provided important guidance for future interface refinements.

Citation:

Giudice, N.A., Guenther, B.A., Kaplan, T.M., Anderson, S.M., Knuesel, R.J., & Cioffi, J.F. (2020). Use of an Indoor navigation system by sighted and blind travelers: Performance Similarities across visual status and age. ACM Transactions on Accessible Computing (TACCESS), 13(3), 1-27.

Download PDF

Evaluation of an accessible, real-time, and infrastructure-free indoor navigation system by blind users in the Mall of America

eblackwood — Tue, 02 Apr 2019 14:34:07 +0000

Introduction: This paper describes an evaluation of MagNav, a speech-based, infrastructure-free indoor navigation system. The research was conducted in the Mall of America, the largest Mall in the country, to empirically investigate the impact of memory load on route-guidance performance.

Methods: Twelve participants who are blind and twelve age-matched sighted controls participated in the study. Comparisons are made for route-guidance performance between use of updated, real-time route instructions (system-aided condition) and a system-unaided (memory-based condition) where the same instructions were only provided in advance of route travel. The sighted controls (who navigated under normal visual perception but used the system for route guidance) represents a best-case comparison benchmark with the BVI participants who used the system.

Results: Results across all three test measures provide compelling behavioral evidence that blind navigators receiving real-time verbal information from the MagNav system performed route travel faster (navigation time), more accurately (fewer errors in reaching the destination), and more confidently (fewer requests for bystander assistance) compared to conditions where the same route information was only available to them in advance of travel. In addition, no statistically-reliable differences were observed for any measure in the system-aided conditions between the BVI and sighted participants. Post-test survey results corroborate the empirical findings, further supporting the efficacy of the MagNav system.

Discussion: This research provides compelling quantitative/qualitative evidence showing the utility of an infrastructure-free, low-memory demand navigation system for supporting route-guidance through complex indoor environments and supports the theory that functionally equivalent navigation performance is possible when access to real-time environmental information is available, irrespective of visual status.

Implications for Designers and Practitioners: Findings provide insight for the importance of developers of accessible navigation systems to employ interfaces that minimize memory demands.

Keywords: indoor navigation system; blind travel; nonvisual navigation; speech-based interfaces

Citation: Giudice, N. A., Whalen, W. E., Riehle, T. H., Anderson, S. M., & Doore, S. A. (2019). Evaluation of an Accessible, Real-Time, and Infrastructure-Free Indoor Navigation System by Users Who Are Blind in the Mall of America. Journal of Visual Impairment & Blindness. Advance online publication:

Download PDF

Indoor Inertial Waypoint Navigation for the Blind

eblackwood — Tue, 01 Oct 2013 18:00:26 +0000

Abstract:

Indoor navigation technology is needed to support seamless mobility for the visually impaired. This paper describes the construction and evaluation of an inertial dead reckoning navigation system that provides real-time auditory guidance along mapped routes. Inertial dead reckoning is a navigation technique coupling step counting together with heading estimation to compute changes in position at each step. The research described here outlines the development and evaluation of a novel navigation system that utilizes information from the mapped route to limit the problematic error accumulation inherent in traditional dead reckoning approaches. The prototype system consists of a wireless inertial sensor unit, placed at the users’ hip, which streams readings to a smartphone processing a navigation algorithm. Pilot human trials were conducted assessing system efficacy by studying route-following performance with blind and sighted subjects using the navigation system with real-time guidance, versus offline verbal directions.

Citation:

Riehle, T. H., Anderson, S. M., Lichter, P. A., Whalen, W.E., & Giudice, N. A. (2013). Indoor inertial waypoint navigation for the blind. Proceedings of the 35th annual IEEE Engineering in Medicine and Biology Conference (EMBC’13, Vol. 2013, pp. 5187-5190).

Download PDF

Indoor magnetic navigation for the blind

Tue, 28 Aug 2012 16:00:31 +0000

Abstract: Indoor navigation technology is needed to support seamless mobility for the visually impaired. This paper describes the construction of and evaluation of a navigation system that infers the users’ location using only magnetic sensing. It is well known that the environments within steel frame structures are subject to significant magnetic distortions. These distortions are persistent and have sufficient strength and spatial characteristics to allow their use as the basis for a location technology. This paper describes the development and evaluation of a prototype magnetic navigation system consisting of a wireless magnetometer placed at the users’ hip streaming magnetic readings to a smartphone running location algorithms. Human trials were conducted to assess the efficacy of the system by studying route-following performance with blind and sighted subjects using the navigation system for realtime guidance.

Citation: Riehle, T. H., Anderson, S. M., Lichter, P. A., Giudice, N. A., Sheikh, S. I., Knuesel, R. J., & Kollmann, D. t. (2012). Indoor magnetic navigation for the blind. Proceedings of the 34th annual IEEE Engineering in Medicine and Biology Conference (EMBC‘12), (Vol. 2012, , pp. 1972-1975).

Download PDF