Ranging sensor advice wanted

[mantrid]

Hi

I'm looking for a physically small ranging sensor that can range up to
about 10ft (about 3 meters) from around 3 inches in.
It doesnt need to be very accurate - small size is more important.

Does anyone have any guidance they could offer?

I have looked at ultrasonic - they tend to be short range and rather bulky
And Laser solutions - tend to have safety issues but I'm not too sure
about those

I was wondering if it was possible to increase ultra-sonic range by somehow focusing the beam and using a single device transducer for tx and rx

Any technology that is reliable, safe to use - reasonably low cost and small
is of interest.

Any suggestions welcome.

TIA

M.

[limor]

you mention laser and ultrasonic in one sentence.
one costs 10$ the other 2000$
what's your budget and application?
single sensor for 3 inch to 10 feet is challenging.

[mantrid]

Hello limor

I think your pricing is quite a bit skewed there...
Although you can spend that much on laser devices if you buy
industrial commercial modules. Others are available that can be
modulated. I did look before coming here.

I know its challenging thats why I'm asking for help.
The application doesn't matter. The problem I have is how best
to approach the ranging issue in a cost effective manner.

[limor]

I would use two sensors one for short range with ultrasound and one for long range maybe with lasers (geometric tricks like NEATO not time-of-flight).

I haven't seen much on DIY LIDAR. There's this component http://www.eodevices.com/main_eodmain_frameset.htm
but once you add the optics you don't really save much compared to HOKUYO

Can you share what you found?

[limor]

Maybe you mean this http://www.parallax.com/StoreSearchResu ... fault.aspx
?

It is a geometry triangulation solution. no modulation or time of flight..

[mantrid]

Thanks for the links - they look well worth checking out.
I've also discovered some ultrasonic transducers that I may be
able to drive to do the job. Or part of it. 10ft appears to be a max for those so I'm guessing they would only work under ideal conditions. (no good to me)
Sure I'll share anything specific I get to test.

[voodoochile]

Check out sharp 2D120x. Cheap to buy & amazing! These are ir range finders. Check out my youtube link. I use 4 of these sensors on my Irowe 4550 robot.

http://www.youtube.com/watch?v=N7GJsiNy5iM

[voodoochile]

Check out sharp 2D120x. Cheap to buy & amazing! These are ir range finders. Check out my youtube link. I use 4 of these sensors on my Irowe 4550 robot.

http://www.youtube.com/watch?v=N7GJsiNy5iM

[mantrid]

Check out sharp 2D120x. Cheap to buy & amazing!

Thanks voodoochile.
I did look at the longer range one (The one you quote only goes up to 30cm) but they don't seem accurate enough or with quite the range I need

The one I looked at http://www.phidgets.com/products.php?ca ... _id=3522_0 would have been very close on acceptable
range but IR is just too unreliable for me in varied settings and the reliability would be aggrovated by working close to max range all the time.

Otherwise a very useful sensor though.