Low-Cost Open Source Ultrasound-Sensing Based Navigational Support for the Visually Impaired

Abstract

Nineteen million Americans have significant vision loss. Over 70% of these are not employed full-time, and more than a quarter live below the poverty line. Globally, there are 36 million blind people, but less than half use white canes or more costly commercial sensory substitutions. The quality of life for visually impaired people is hampered by the resultant lack of independence. To help alleviate these challenges this study reports on the development of a low-cost, open-source ultrasound-based navigational support system in the form of a wearable bracelet to allow people with the lost vision to navigate, orient themselves in their surroundings and avoid obstacles when moving. The system can be largely made with digitally distributed manufacturing using low-cost 3-D printing/milling. It conveys point-distance information by utilizing the natural active sensing approach and modulates measurements into haptic feedback with various vibration patterns within the four-meter range. It does not require complex calibrations and training, consists of the small number of available and inexpensive components, and can be used as an independent addition to traditional tools. Sighted blindfolded participants successfully demonstrated the device for nine primary everyday navigation and guidance tasks including indoor and outdoor navigation and avoiding collisions with other pedestrians.

A Systematic Review of Wearable Devices for Orientation and Mobility of Adults With Visual Impairment and Blindness

“…The findings of this review highlight directions for future development and research. A major concern observed in our review was the size of the device, more specifically, the miniaturization of the device [7], [32], [44], [46], [48], [52], [61]. A similar concern was reported by Kuriakose et al [83], who reported a relationship between the device's size and its adoption.…”

“…Among sensor-based technologies, ultrasonic sensors were the most used in the included studies (n = 24). The use of ultrasonic sensors has demonstrated several benefits for mobility performance, including a decrease in navigation time [13], [36], [63], and detection of complex obstacles such as stairs [13], [36] and moving obstacles [7].…”

“…In addition, since most visually impaired people live in low-and middle-income countries, low-cost is a concern that needs to be taken into consideration. Several studies have reported suggestions for reducing the costs of the devices, including the use of additive manufacturing technologies [7], [73], [80], the implementation of opensource programming [7], [28], [33], [37], [77], [79], and the use of cloud servers, which eliminates the need for using an expensive high-performance processor [33]. An example is observed in Petsiuk and Pearce [7], whose prototype with 3D…”

“…To have efficient and safe mobility, a visually impaired person relies on assistive technologies such as white canes, guide dogs, or electronic devices [4]. Although white canes and guide dogs are the most commonly used assistive technologies, they can only partially resolve safe and independent mobility [7], [8]. White canes have a short range for obstacles at ground level and cannot identify obstacles above the waist level [9].…”

Identification of Markers in Challenging Conditions for People with Visual Impairment Using Convolutional Neural Network

“…As a result, multiple researches have been carried out to help PVI in indoor navigation and identifying products in shops or other objects using Wi-Fi, Bluetooth, RFID, NFC, and tags. These solutions differ in the types of the signals used, the positioning method, and the accuracy [12][13][14][15][16][17][18][19]. These solutions fall into three categories: Tag Based Systems: Such as radio-frequency identification (RFID) and near field communication (NFC), which use wireless components to transfer data from a tag attached to an object for the purpose of automatic identification and tracking [20,21].…”