What are the options for long range distance sensors?

[bassplayer142]

Can anyone point me to a long range distance sensor. I'm not sure what types they have out there other then ultrasonic. Those ones only get me about 10-80 cm. I'm looking for one that is around 30ft or more. Any information on different types of links is appreciated. thanks in advance!

 

[berkeman]

I googled Laser Rangefinder, and got a bzillion hits. Hunters and golfers use them, so hopefully you can find one in your price range. There's a wikipedia.org article on them as well.

 

[mgb_phys]

There are two types of laser rangefinder depending on your application.
Phase measuring (the red dot ones at your local DIY store) are good to about 30ft and provide an accuracy of fractions of a mm. But they are slow, several seconds for a stable reading, and don't work if there is a lot of ambient light, they work better indoors.
Time-fo-flight (as used in theodolites and golf scopes) they are fast, 100,000 readings/sec if you want, long range,upto 10km, but less accurate (1-10cm).
You can improve the range and accuracy of both if you can put a reflector on the target.

 

[MATLABdude]

Do you need scanning (e.g. a 2D obstacle map)? Or just point-and-range? Regardless, when I did this sort of thing a few years ago, SICK was king of the hill (and their products were priced accordingly--but they were really, really good):
http://www.sickusa.com/gus/en.html

 

[mgb_phys]

Or http://www.mdl.co.uk/laser_modules/laserace-im/index.html