Blind and low-vision people today mostly rely on a white cane or a guide dog. Maker DebackTech wanted to see if a low-profile wearable could add a sense of the space around them, and built a pair of glasses with three small LiDAR sensors that turn distance into touch through 16 vibration motors sewn into a shirt. He then tested them in downtown Boston and in a blindfolded game of catch.
How the glasses work
Two wide depth sensors on the frame scan ahead, covering about 120 degrees and up to 5 m. A third sensor is angled 40 degrees down to watch the ground for curbs and drop-offs. An IMU tracks head tilt, so looking down at the floor does not register as an obstacle. Each sensor times how long light takes to bounce back from many points at once, so it returns a small grid of distances, a low-resolution depth image, instead of a single reading. The maker started with a 64-point sensor, found the resolution too low and moved to 512-point sensors.
A Raspberry Pi 4 in a pocket merges the three sensors into one depth map. Each point is checked against its neighbours so stray readings do not fire a motor. The output goes to 16 vibration motors on the chest and torso, driven from a protoboard of motor drivers. Columns map to direction and rows to height, from uneven ground and trip level up to torso height and overhead. The closer an object is, the harder that motor pulses. The rig runs for about 8 hours.
What the tests showed
Stray light was the biggest problem, and it got worse outdoors in sunlight, so the maker added heavy filtering on each sensor point. Catching a ball proved harder. The sensors deliver about 13 frames per second, so a ball thrown at around 25 mph is seen in only about five frames. The maker added trajectory prediction, using the first three or four frames to estimate where the ball is going and alert the wearer earlier, but motor spin-up and human reaction time still left too little margin for consistent catches.
Our take
This is an honest prototype, with cables everywhere and an open list of limitations, but the design choices are worth studying: a downward sensor for curbs, IMU-based tilt compensation, and a body map where location means direction. The maker is asking blind and low-vision users what would actually help before a version two. To try multi-point distance sensing yourself, see our VL53L5CX obstacle-avoiding vehicle project.
Image credit: DebackTech, frame from the maker's video, cropped and resized.
About the author: Aswinth Raj is an electronics engineer and the editor of CircuitDigest, where he has published more than 150 hands-on projects and tutorials across Arduino, PIC, ESP32, Raspberry Pi and EV battery systems. He selects the stories on this page for what engineers and makers can actually learn or build from. Connect on LinkedIn
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