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View Full Version : Rotary Laser Sensor



jdolecki
11-15-2007, 02:48 PM
Has anybody thought about converting one of those Rotary Laser Levels into a sensor?

The cheapest one i see on the web is about 2k But those Rotary laser levels can be had for a few bucks.

Anybody have any thoughts?

kdwyer
11-15-2007, 04:51 PM
To sense what?
I found a few reasonably inexpensive bullet lasers, and matching collimating lens (the lens spreads the laser dot into a fan-type line). Mounted on a panning servo, you get a cool 'scanning' line back and forth. I have one of these on Otto (who STILL isn't finished!) In a smokey room it is TOO cool for words.
To use a laser as a sensor, you have to ... I have no idea. Track the dot? Get feedback from laser scattering? Bounce the beam and measure the time?

Nammo
11-16-2007, 12:27 AM
I've seen some people using rotary lasers for structured vision. They point a camera at the pattern the laser draws on the world. One approach detects the laser in the field of view by taking a picture with the laser off, then quickly taking a second picture with the laser on. Subtract the first picture from the second and the result will be a single line on a dark field. Now, in each column of the picture, the height of the line will tell you the distance of the object the laser encountered in that column.

The result is not as accurate as a 'real' laser scanner, but it is pretty computationally cheap to implement and can work very well in the right environment. Google 'structured vision' for more examples.

jdolecki
11-17-2007, 08:46 AM
I was thinking collision avoidance. The Sick laser sensor is several thousand dollars. There is one from China? but that is 2k. All the Darpa challange teams have several on there vehicles.