“Flashlight” for the blind

My grandfather was almost completely blind, so i rigged up this little device for him. The goal was to detect obstacles out to about 3 meters, and warn him as he approached them. I simply put a phone vibrator (he was deaf too) and a small buzzer in a case connected to an ultrasonic sensor.

basic code on an arduino probes the sensor, and if it receives a measurement under 3 meters it vibrates and beeps, the closer the obstacle, the more frequent the beeps. The result was a tactile means of finding his way around, he assured me he could find the mail box for the first time in a few decades.

limitations/ future work.

• power management needs to be handled more aggressively. 9v batteries drop to 7 volts very quickly, and thats barely enough for 7805 regulator to output 5v, ive since found low drop out switching regulators.
• obviously ergonomics need a bunch of attention.
• the ultrasonic sensor is not good at detecting thin objects,
• maybe it could automatically sleep when no motion is detected?