This project uses ultrasonic sensors connected to an Arduino Pro and servos that nudge the wearer when an obstruction is detected.
It’s wrist mounted and senses objects from about 1 inch (2 cm) to 10 feet (3.5m). It has generally fast response time (fractions of a second) to quickly navigate complex environments. It’s designed to help a vision impaired person to navigate complex environments. Mounted to the back of the hand, the force feedback means it doesn’t interfere with other assistance devices that mount elsewhere and use audio feedback cues. The learning curve is measured in seconds, everyone who has worn it has figured it out immediately.