[sci.electronics] Laser vs. Ultrasonic Surveying?

richard@pegasus.com (Richard Foulk) (10/16/90)

I was talking with a friend last night about lasers and stuff, and he
mentioned that he had used some sort of laser arrangement to help build
straight walls on a heavy construction job.  The laser apparently
employed a spinning mirror to map out the whole plane of a wall.

He said they stopped using the laser after a while because it was such
a hassle to post all of the necessary "Eye Hazard" warning signs.  They
switched to an ultrasonic system instead.

He didn't have many details but said that it worked quite well.  My
question is; how would such an arrangement work?  I understand how the
sonar tape measures work, but how would you replace the laser system
that I've described above with something based on ultrasonics?


-- 
Richard Foulk		richard@pegasus.com