iPi Studio Motion Capture Test: Sword Prop

The was a test to see if a physical prop could be used without interfering with the tracking process. The prop used was a Nerf sword purchased from a local toy store. We considered this test successful. Might have to try the Nerf battle axe next. :)

The motion was captured using four Playstation 3 Eye cameras set to 640 x 480 at 30fps. Tracking ran smoothly with no error correction necessary (note that DMC doesn't capture head motion yet.) A single pass of Jitter Removal had to be applied, which seems to be normal and expected.

I'm looking forward to when iPi DMC can capture prop motion. If we got just a single bone for this sword, that would be so awesome.

Feel free to ask any questions about this session.

Greenlaw

_________________
Greenlaw
Artist/Partner - Little Green Dog | My Demo Reels (2013,) (2015,) (2017,) and (2019)

Watch a one minute excerpt on Vimeo now!

Looks like a very solid capture ! (You're not too bad with a sword, also ^^)

How where your cams setup exactly ?

Thanks. :)

I haven't moved the cameras since doing that test, so I'll try to map the positions out tonight and post the info here. It's pretty straightforward though: the cameras are in a semi-circle configuration, almost but not quite 180 I think. I only measured the height of 'camera 1', but they are all between 2 - 3 meters up. The cameras are maybe 10 to 12 feet away from the center of the 'stage'. These numbers are guesses; I'll post actual measurements later.

BTW, I made rigs to semi-permanently mount the cameras to the walls, and I'll post info about this later. I'm using parts mostly purchased from a local hardware store and it's a little cheaper than buying security camera (CCTV) mounts. If you don't want to build your own mounts, you can get actual security camera mounts on ebay for pretty cheap, but in many cases the shipping cost makes them expensive, so be careful when ordering.

I should add that you will need to modify the PS3 Eye camera base to make this work, which is pretty easy to do with a kit and a few tools. I basically followed the instructions somebody else posted here a couple of months ago, but with a few tweaks of my own. I made a detailed video about this and I'll try to post it on our YouTube channel later this week.

G

_________________
Greenlaw
Artist/Partner - Little Green Dog | My Demo Reels (2013,) (2015,) (2017,) and (2019)

Watch a one minute excerpt on Vimeo now!

Goo to know I'm not the only one that thought about some wall-stands...

BTW, about capturing with props, I can't test until I can have a correct mocap session for the moment, but I figured something that could be useful. If you need large or complex propos that probably will obscure your actor and mess up the mocap (like say a big box or a shield or whatever), why not making a model of it in metallic wire ?

I'll test that as soon as I can. From past experience, metallic wire can be too fragile, so I would use some old metallic clothes hangers. That's way more robust and still easy to bend. And easy to find.

Only downside to this solution is you won't have the same weight as a real prop... but hey, I believe ipi Desktop wouldn't be bothered by some thin metallic wires...

That's a good idea! Thanks. I was thinking about larger 'proxy' props, but didn't have any specific ideas about how to do it yet.

My wife wanted to try an actual guitar or ukelele, which she thinks should work because her arms will still be visible. That seems to makes sense, but if it didn't work I was thinking the 'instrument' might have to be transparent without being shiny. Your idea of constructing a proxy out of wire should work.

It may be little while before I can get back to testing, but I'll let you know how it goes. Right now I'm focusing on getting a character animated and rendered with this data.

_________________
Greenlaw
Artist/Partner - Little Green Dog | My Demo Reels (2013,) (2015,) (2017,) and (2019)

Watch a one minute excerpt on Vimeo now!

Thanks for posting this video! It looks great!

Can we post a link to it in our Gallery page? What description should we put - "Video courtesy of D.R.Greenlow, Little Green Dog" or "Video courtesy of D.R.Greenlow, Rhythm & Hues Studios" or something else? Can we show this video in our SIGGRAPH booth, with appropriate subtitle?

Michael,

Of course! The tagline "Courtesy of Little Green Dog" is fine and a link to http://www.littlegreendog.com.

Even though I work for Rhythm & Hues, my experiments with iPi Studio have been on my own time and for personal projects. That said, my boss and coworkers at R&H are greatly interested in what I've been doing with this system, so who knows?

Anyway, I should have more iPi related videos after this weekend, which you may also use for marketing if you wish.

Greenlaw

_________________
Greenlaw
Artist/Partner - Little Green Dog | My Demo Reels (2013,) (2015,) (2017,) and (2019)

Watch a one minute excerpt on Vimeo now!