AAL-based smart cane system with security and privacy features for blind and visually impaired individuals

Ambient Assisted Living (AAL) technologies aim at increasing the quality of life for people with impairments. Practicality, reliability, autonomy, ease-of-use, safety, and low cost are of the utmost importance and in some cases omitted or overlooked by the research community. In this paper, an AAL-based smart cane system with security and privacy features for blind and visually impaired individuals that aims at satisfying these requirements is proposed. Multiple services that facilitate the everyday life for both indoor and outdoor activities are implemented: obstacle detection for ground and head level via ultrasonic (US) sensors and vibrations, ascending and descending stair detection/recognition via computer vision, image processing through various sensors, an emergency button for additional safety, and a LoRa antenna with a security and privacy mechanism for safely communicating with the Health 4.0-based environment. The proposed system is implemented with an Arduino and Raspberry Pi Zero combination and provides more practical and economic services compared to other published related works, including head-level detection, an indoor-outdoor adjustment switch and security mechanisms that are in most cases dismissed. It achieves a 7.4 % accuracy increase for general obstacle detection and a 100 % consistent drop or wall detection accuracy compared to published works. The proposed system presents a 37.82 % increase of speed-adjusted recall and a 24.4 % performance increase in its stair detection feature compared to published works. It focuses on hardware efficiency, safety and real-world autonomy with cost efficient alternatives. The proposed architecture of the security mechanism achieves a small area consumption, minimum of 35.6 % decrease compared to published designs, and an efficient throughput, that is appropriate with the utilized antenna.