Smart Glasses: Portable Navigation Aid for the Visually Impaired with Object Detection and Monocular Depth Estimation

More than 2.2 billion people worldwide have impaired near or distance vision, with about 4.95 million people, including 240,000 children, in India being blind and 70 million visually impaired people. These individuals find it hard to navigate through an unfamiliar environments and to identify objects. Existing navigation aids are usually bulky and can’t be used on a day-to-day basis. Smart Glasses were developed to improve the lives of visually impaired people by enabling them to navigate their surroundings effectively. The device comprises a USB camera mounted on a pair of eyeglasses for live video capturing of the user’s surroundings, a Raspberry Pi 4 running a Python program utilizing YOLOv10 for detecting objects while the MiDaS model estimates the distance of the detected objects, and audio feedback about that through an earphone to the user. MiDaS performs monocular depth estimation using its encoder-decoder architecture, ResNet-based backbone, use of skip connections, and multi-scale feature fusion. Smart Glasses was tested in a sequence of controlled tests to determine its capabilities in object detection, of various commonly encountered objects. It managed to achieve an overall detection accuracy of about 93%. For specific objects such as apple, person, and car, specifically, detection accuracy was 94%, whereas for tables, benches and cellphones, it was 95%. The detection accuracy for a chair was 90%. Detection accuracy for objects in the category of transport (motorcycles, buses, trucks and stop signs) ranged between 92 and 94%, ensuring outdoor navigation safety. The depth estimation was also found to be reliable, with proximity of the nearest objects estimated correctly 90% of the time, and for the farthest, it was 94%, confirming the system’s aptitude for spatial awareness. These results indicate Smart Glasses can empower the navigation capability of visually impaired individuals and hence exceeded traditional assistive devices. Five completely blind people took part in the testing of the device at Devnar School for the Blind, Hyderabad. Each participant wore the glasses for 10 minutes and was asked to describe the experience of understanding their surroundings during that period. The users appreciated the glasses for their daily use and requested features such as book reading, multilingual audio feedback (Telugu and Hindi), and facial recognition.