4D Motion Tracking
rjo_
Posts: 1,825
I'll be detailing this project over the next week or so. All of the pieces are working... now it is just a matter of getting the mechanics right and crunching numbers[noparse]:)[/noparse]
The concept is to use stereo line scanned images, which are exactly synchronized, to acquire motion data over time and store that data to an SD card.
Getting the two TSL1401's synchronized turned out to be a piece of cake. Both TSL's are controlled with the same pins coming from the Prop.
The two analog signals (from each TSL1401) then go into channels 0 and 1 of the MCP3208.
I have room for a 3rd Prop... so I expect that I'll be using that for near time analysis and display.
Since I'm a stereo buff... I'll also be taking stereo pictures with this same basic setup.
AND since we are all robotics enthusiasts... I will be adding a laser to get object distances in a quick and dirty way.
Notice the noise in the upper left hand corner of the TSL1401 scans... handy evidence that it is time to disgorge your code!-[noparse]:)[/noparse]
ILMP
Rich
The concept is to use stereo line scanned images, which are exactly synchronized, to acquire motion data over time and store that data to an SD card.
Getting the two TSL1401's synchronized turned out to be a piece of cake. Both TSL's are controlled with the same pins coming from the Prop.
The two analog signals (from each TSL1401) then go into channels 0 and 1 of the MCP3208.
I have room for a 3rd Prop... so I expect that I'll be using that for near time analysis and display.
Since I'm a stereo buff... I'll also be taking stereo pictures with this same basic setup.
AND since we are all robotics enthusiasts... I will be adding a laser to get object distances in a quick and dirty way.
Notice the noise in the upper left hand corner of the TSL1401 scans... handy evidence that it is time to disgorge your code!-[noparse]:)[/noparse]
ILMP
Rich
640 x 480 - 64K
640 x 480 - 46K
720 x 480 - 13K
720 x 480 - 13K
Comments
Just wanted to see if I could make it work. But now that you mention it ... that little dog driving my car has been poo-ing in my ex's basement.
I think it is her fault... She swears it is my fault. This could settle the argument.
Propellers to the rescue!!!!
Seriously, I am expecting a Propeller paintball contest... and I want to be ready.
Rich
$3 Walmart
Oh, this is like google earth streetview?
4D is one more than 3D[noparse]:)[/noparse]
When you come to OTTAWA for Oldbit's meeting... remind me to take you to the Roxy Theater across the street. It seems like every movie that comes along is advertised as being in 3D these days. Hopefully, one of these will be playing. You will swear that a 3D movie at the Roxy is exactly like every other movie... no funny glasses, nothing jumping off the screen... nothing at all. So, I think that Hollywood might have caught on to your idea that time is the third dimension and that all movies are 3D... since that seems to be the way they are advertising them, and they don't look any different to me... what other conclusion can we conclude?
So, if time is the 3rd dimension... then the Z-axis would be the 4th dimension.
Since I am using "linear" arrays, I wondered whether I was cheating. I considered calling it 3 1/2D, but I'm not really sure that half a dimension is allowed in physics... I wouldn't want to break any laws[noparse]:)[/noparse]
I also considered calling it "Diachronic Motion Analysis in 3D," but that sounded a little too snooty and a little redundant since all motion happens over some increment of time[noparse]:)[/noparse]
Rich
Post Edited (rjo_) : 2/12/2010 5:53:11 AM GMT
By definition, Fractals can have fractional dimensions. That includes coastlines, but I am not sure
if a coastline (of an island) has more or less than 1 or 2 dimensions. My guess is, a 1 plus some loose change.
I think it is something like the maximum (limit) amount of space it can occupy over the minimum
amount of space and dimensions it can fit in, but that's not the exact definition of fractal dimensions.
The fractal that's all triangles has around 1+1/2 dimensions. So my rough math definition seems inverse.
You have again put your finger on the crux of it.
Is it a dimension simply because we decide that it is a dimension?
Should we have real dimensions and imaginary dimensions? What is a universe described by an imaginary dimensions?
Does time actually exist, or can we just define it any way we like? (Just because we have double vision does not mean that for a brief moment, everything exists in pairs. Just because we sense time does not mean that it exists in the way that we experience it or even that it exists at all.) Clocks exist... maybe the 3D dimension should be a master clock, which allows the serial representation of the entire universe of events?
And most importantly... what is currently the absolute fastest way to write to an SDCard with a Prop? Who holds the current record? how did he achieve this record?
I am getting 128 bytes from a TSL1401 in around 3 milliseconds.... in SPIN... and I am about to code it in PASM, but my write times to the SD card are glacial. What is the best I can do?
Rich
Um... a few people are working on speeding up the SD, I'm not sure who is fastest,
I don't think all the bugs are out of the latest versions of fsrw, maybe someone else knows.
Kye has an advanced version being debugged lately, but I don't know how fast it is.
Maybe the recent WAV player has a fast SD object? I've been looking too, but I don't know all the details.
Thanks again,
Rich
Thanks to the help of rokiki and lonesock, I have achieved orbital momentum and am now walking on clouds[noparse]:)[/noparse]
I haven't made an effort to document this yet, because I intend to immediately change it. This is a proof of concept to my brain... that what I think can be done... can in fact be done. It can... now it is time to do it right.
As proof to your brain, please see the stereo self portraits included. These were obtained by slowly rotating the imaging board around the long axis... manually.... while holding down the save to SD button. In the first I look like an alien... in the second I am clearly human, but nothing you would invite to dinner. If I had been wearing a tux in the third, you would have been able to see it in the third image. I wasn't and you can't... but not bad for a hand held stereo pair!!!
These are 8 bit images... in the next version, they will be 16 bit images acquired by automatically rotating the TSL1401 camera. This version uses two Props... the next will use 3. One for acquisition, one for display and one for control. Lots of buttons and knobs!!!!
No motion tracking or ranging data yet... that comes next.
I would like to note that working with the TSL1401 is not only fun... it might improve your bowling. Last night at Special Bowling league, I scored a 40 year high series of 450!!!.
I'll be out til late tonight.
Thanks guys.
Rich
By the way, I went to your web site... and it is wonderful. And as far as I know, it is actually a new concept... free hosting... well almost free... for bot people only. That is fabulous. I'm new to building robots, so I am trying to sneak up on one and see if I can get it do my bidding. The other premise on your site... is that there should be somewhere for people to go... to find all of those little parts that you can't find anywhere else.
Take a look through Parallax's store... notice all of the nuts and little tiny bolts that aren't there. Where are the little gears for the little motors?.... This might not be an issue for other people... but it is starting to aggravate me.
flat plastic with holes drilled to meet the form factor of every blessed product... nothing. If you want it... you have to do it yourself and if you can't do it... you are SOL.
So... it isn't fully formed. But it is certainly something that the guys around here should support.
Regards,
Rich
Post Edited (rjo_) : 2/14/2010 2:39:15 AM GMT
smallparts.com
microfasteners.com
http://forums.parallaxinc.com/secure.microplastics.com
-Phil
I would follow you anywhere... just point the direction[noparse]:)[/noparse]
Rich
math.rice.edu/~lanius/fractals/dim.html
On the websites, don't forget:
http://www.mcmaster.com/ ' for everything bigger than 1/4" and the best website ever
http://www.grainger.com/Grainger/wwg/start.shtml ' for stuff at McMaster Carr at a slightly better price sometimes
http://www.digikey.com/ ' all things electronic and a data sheet wonderland
http://allelectronics.com/ ' the robotic internet version of that dusty old ham radio shop full of the coolest stuff - "Where do you get this junk?"
http://www.npcrobotics.com/ ' National Power Chair for rebuilt motors and transmissions
I'd bet erco has a great collection of links too!
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Signature space for rent!
Send $1 to CannibalRobotics.com.
Thanks for the links.
To see the spinal tap moment in all its glory see: www.youtube.com/watch?v=EbVKWCpNFhY
The last two seconds are the best.
Graham