What's that sound? Distance determination and aperture passage from ultrasound echoes

Abstract

The ability to judge distance and navigate through an environment with obstacles using a device which audifies ultrasound was shown to be better than using auditory echolocation, but not as effective as vision. This device will allow individuals with visual impairments to better detect and avoid environmental obstacles.

Blindness enhances auditory obstacle circumvention: Assessing echolocation, sensory substitution, and visual-based navigation

“…The SSD training phase was similar to the auditory guidance training, except that practice with the small obstacle and static detection of the large obstacle were not included, as in this condition participants did not need to become familiar with producing sounds and the device always allowed them to detect the obstacle if it was present. In previous experiments that assessed the use of an echoic SSD for aperture navigation, training with the device lasted approximately 5 minutes [42, 53]. To provide greater training with the SSD than provided in these experiments, participants practiced circumventing the large obstacle using the SSD from an approach distance of 1.75 m, for at least 15 minutes.…”

Sensory substitution information informs locomotor adjustments when walking through apertures

“…The device made a short chirp sound which increased in rate as distance between the device and an obstacle decreased. Both devices were set to have a range of 1 m. Two devices were utilized in the experiment to verify that the 9 findings generalized across two sensory substitution devices which differed in the method of audification of distance information, as previous studies have tested only single devices (Hughes 2001;Davies et al 2011). While using the devices, participants were instructed to tuck their elbow against their side to prevent arm movements in an anterior/posterior direction, and to hold the hand with the device perpendicular to the body.…”

“…For the two SSD conditions, training was provided prior to testing. In the studies of Hughes (2001) and Davies et al (2011), participants received approximately 5 minutes of free training using a single SSD. In order to extend our participants' learning during the training phase beyond that of these studies, we gave our participants 15 minutes training for each of the two SSDs studied, and utilized two different aperture widths for this purpose (smaller and larger), in addition to three phases of training (SSD plus vision, SSD plus vision when required, and SSD only).…”

“…Visual-to-auditory devices that work on an echolocation principle have previously been used to study whether SSD information regarding aperture width size can be used by blindfolded participants (Hughes 2001;Davies et al 2011), or to provide spatial information to visually impaired patients (Kay 1964;Heyes 1984;Laurent and Christian 2007;Roentgen et al 2008;Roentgen et al 2009). Hughes (2001 demonstrated that an echolocation system (Kay's Advanced Spatial Perception Aid KASPA™) was able to provide naïve blindfolded users with spatial information regarding locomotor guidance and aperture width between wall panels, suggesting that information embedded within the echoic spatiotemporal flow field provided by the device made spatial layout information available to the user.…”

1G-30 Literature survey on the current information and communication assistive technology devices

“…Most devices for those who suffer from blindness or low vision provide functions that support the perception of text, images, and geological location [8][9][10][11][12][13]. This is a somewhat trivial result, due to the limitation of visual information inherent in the disabilities.…”