1) The most dangerous obstacles are not at head level. Furniture and most of the other things that can be tripped over and stubbed on are waist level or lower.
2) Vibrating motors stuck on your skull will drive you insane quickly.
In addition it would be a challenge to disguise it as anything but some mad-science-looking headband, and blind people do care how they look.
The headband was a great first test, and it did work, but it had two fatal flaws:
Current Music: Substanz T -- Hypnotizing Low Vibrating Frequencies ♬