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DC Robotic
05-08-2009, 06:38 PM
OK, I'm ready to start working with vision. I could use some advice, specifically on hardware.

What I want to do is have a camera onboard, and process the signals and control the robot remotely via a PC. Ideally the system would be capable of using for 2010 mechwar. Meanwhile I would like to use it on a rover and to test some Industrial applications. I would prefer a somewhat plug and play sytem to something that reqires lots of fiddly configuration. Having a fairly robust and capable system is more important (slightly) that budget. I would prefer to do the application programming in C#. What I am hoping to avoid is buying hardware that is not really what I want or what is best suited to my requirements.

Questions:

1)What's working for the mechwarriors?
2)What Wireless Technology is being used?
3)RoboRealm seems to be a popular vision processing application, is it suitale for learning vision and how far will it take me?
4)What are the limitations to a wifi webcam, which would seem to be the most off-the-shelf solution?

Thanks in advance four your thoughts.:)

darkback2
05-08-2009, 09:41 PM
check out the trendnet line. They are IP cameras. On the PC side, I would go with a Xbee pro for sending data to your micro controller...You can take the video streight into roborealm, and probably other software too.

Hope this helps.

Db

Adrenalynn
05-09-2009, 03:11 AM
They're not really "the Amazon line". You can buy them locally here, or in a bazillion online stores - they're made by Trendnet. I found mine cheaper in Fry's electronics than Amazon had it for. The 110W is a pretty nice IP camera for the money. It's 802.11g

Roborealm is a good starting point for proving concepts. If you need speed, you'll end-up porting away from Roborealm probably at some point...

scowby
06-01-2009, 10:40 PM
I guess one of the questions I would have is: what type of interface are you putting the camera into? Like, what is "reading" the video feed in order to make the robot "see?" Are you running OpenCV under linux, and the computer picks up the video feed...how?

What about a standard security camera with a video-capture card? Would that work?

Noodle
06-02-2009, 12:12 AM
I guess one of the questions I would have is: what type of interface are you putting the camera into? Like, what is "reading" the video feed in order to make the robot "see?" Are you running OpenCV under linux, and the computer picks up the video feed...how?

What about a standard security camera with a video-capture card? Would that work?
That should work. In linux it just looks for an input video feed, and a capture card is just VGA to input. So it should work. I need to try this for my own project. Webcam works.

lnxfergy
06-02-2009, 12:18 AM
One of the requirements above was "able to use for mechwars 2010"... which means the system must work at robogames.. one of the harshest RF environments outside of outer space... The signal from a standard wireless security camera will probably get obliterated there.

-Fergs

Adrenalynn
06-02-2009, 01:08 AM
Just a technical note: A security camera is NTSC (or PAL), not VGA - or more accurately, it's Composite not RGB/sync-on-green.

It's actually nigh-on-impossible to find a reasonably priced VGA capture device. You can use an RGB capture card (serious money) and do some magic with sync and build/buy an adapter and capture it that way though... Of course, it's all but impossible to find a camera that spits-out VGA, so it doesn't really matter in practice. Grabbing the screen buffer (since monitors are traditionally VGA/SVGA/XGA/SXGA/etc.) is generally how one would go about grabbing the image from the screen anyway.


Yes, a capture card that is WDM or v4l (windows vs linux) will work fine for video processing at a "normal resolution". So will any USB-fed device that is WDM or v4l.

Basically it all comes down to the drivers...

scowby
06-11-2009, 11:17 AM
Hey DC Robotic - did you ever figure out what you're going to do with this?

DC Robotic
06-11-2009, 01:52 PM
Yes, I bought the Trendnet Webcam. I was able to hook it to the bot and run it around the room. I controll tht bot wirelessley and just open a browser window right now. Will be working on Roborealm soon. The hitch I ran into was no 5V of adequate amperage. I'm guessing it draws about 1.25A. I ran it from the lipo 2s (7.4V) through an old RC BEC I tore out of one of my sailplanes. Worked fine but got hot quick. I have ordered one of the nifty switching voltage converters from Dimension Engineering which will fix it. I am sort of sidetracked at the moment as I'm building a CNC router table to facilitate parts building. I'm also getting a new Knee at the end of the month (Old Skiing and MTB riding injury) So should have quite a bit of time to study C# and Roborealm!

Adrenalynn
06-11-2009, 01:59 PM
Jes and I have both been seeing around 800mA peak, if I recall.

The camera naturally runs pretty hot. I suspect the regulator is a bit under-rated.