Sunday, August 22, 2010

How the dart was illuminated

Did you watch the video in my last post? If not, you may want to do that before reading on.

Here are my thoughts on how the dart was illuminated. I think there are two parts to it.

First, we see an LED ringlight around each camera but they never appear to fire up. Additionally, there appears to be a filter over each lens. My guess is that the lighting is infrared and the lenses are each covered with an IR bandpass filter. That would allow the system builder to strobe the lights without blinding anyone watching.

This much was also deduced by the first person to post a comment, but I think there's more to it than just the use of IR. Did you notice the big shroud over the dart’s flightpath? I think that does much more than just keep out ambient light: I suspect that the ringlights light it up so it acts as a giant backlight. And to that end, the shroud is probably not made of any old cardboard but rather, is formed from a material selected specifically for its ability to bounce light around.

Well that’s how I’d do it anyway.

Now if you read the second comment, from Andy Wilson of Vision Systems Design, you'll know that this demo is not exactly novel. Like Andy, I'm a little surprised that NI would replicate what someone else has already done. Yes, I know the NI system has to work faster than its predecessor, but what they've done isn't really awe-inspiring.

2 comments:

Anonymous said...

Actually when watching the video in engineeringtv.com (without crap blocking the bottom of screen), you can see those lights lit, with light bluish color.

Anonymous said...

I actually found explanation of the system, see here: http://www.sisudevices.com/pages.php?pageid=22