Building a 3d pointcloud from rotating 2d lidar with a SICK LMS 291/s14 and high resolution optical encoder
Greetings, ROS is fabulous and thanks to all contributors!
I was wondering if anyone had experience rotating a 2d laser to produce 3d pointcloud and how to advertise/visualize using ROS?
- Secured a SICK LMS 291 S14.
- Built a rotating platform with high resolution optical encoder
(Heidenhain ERN420) I have both the SICK laser and the PhidgetEncoder talking with ROS.
- I have a 5 pole slipring rated to high rpm
- I would like to
construct a point cloud from this
next, and not reinvent the pointcloud
wheel, hopefully re-using as much
c/c++ code from ros as possible...
I had a look at player/stage LaserPTZCloud driver and I was going to write something similar, but before I dive into this wanted some expertise..
I was trying to build something similar to the following, but I cannot post links because of karma points
Any thoughts or suggestions of how to proceed or if someone has done this before and can provide specific code examples would be appreciated...
-05/15/2013 Edit: After running the tutorial for laser_scan_assembler and periodic_snapshotter I have learned a great deal. My question would be how was the tilt_scan topic built? All that is mentioned is
"The tilt_scan topic was recorded from a planar laser mounted on a tilting stage. The /tf topic contains the robot transforms."
Is there a code example of how this was built?
Update 05/30/2013 Finally figured it out, and yes I needed to learn tf very well to do this. If you have questions learn TF! Thanks for pointing me in the right direction!!
Few other stumbling blocks that I had along the way. I had a SIIG SII206M. SIIG Inc. USB to RS-422/485 Converter, but did not get 500kb baud (only got 38K), I even wrote my own driver, and achieved 230kb, then I bought a USB-COMi-M http://sewelldirect.com/USB-to-Serial-RS-232-rs-422-rs-485-DB9-and-6-pin-Terminal-Block.asp and it works perfectly with the sicktoolbox-wrapper provided.
You may also want to check out https://www.sparkfun.com/products/9822, as it is cheaper, I went with one I knew some papers had documentation on.
I had to re-write the encoder phidgets package, as they have updated their library, I used their high-speed encoder but there was some #ifdef's that didn't apply anymore... also the high_speed_encoder had to init() the encoders before using them otherwise didn't work..
I also wrote my own periodic_snapshotter2 based off the original, just modified for pointcloud2 data, figured it may be more useful in the future.
For anyone else that needs help or is trying to do something similar, the nootrix image http://nootrix.com/2013/01/virtualized-ros-groovy/ is an excellent way to get started developing on ubuntu, then I recommend creating your own package to customize/copy/re-use source code for your own robot.
This was a very cool and interesting challenge, I am now able to generate pointclouds that consist of 78398 points every 4 seconds, published into rviz. The unit itself turns 360 ...
