EchoVis: Training Echolocation Using Binaural Recordings – Initial Benchmark Results

In this paper, we describe a recently begun project aimed at teaching of echolocation using a mobile game. The presented research concerns initial echolocation tests with real world obstacles and similar tests performed using binaural recordings. Tests that included detection and recognition of large obstacles in various environments (padded room, non-padded room, outdoors) were performed by three groups 10 persons each: blind children, blind adults and sighted adults. A mixed group of volunteers also tested binaural recordings of the same environments using a mobile application for Android and iOS devices. The presented preliminary research shows a large variance in echolocation ability of the participants. Less than 20% of the 30 volunteers could reliably (with >80% certainty) localize 1 m and 2 m wide walls at distances 1 to 3 m, while about as many showed no echolocation skills and answered at a random level. On average sighted adults performed better in echolocation tests than blind children, but worse than blind adults. Tests in outdoor environments showed much better results than indoors and a padded room was marginally better for echolocation than the non-padded room. Performance with recordings was generally worse than in analogous real tests, but the same trends could be clearly observed, e.g. a proportional drop-off of correctness with distance. The tests with recordings also demonstrated that a repeatable pre-recorded or synthesized clicker originating from a loudspeaker was a better solution than recordings with live clicker sounds.