http://www.tomsguide.com/us/Xbox-360-Project-Natal-Space-Required,news-6220.html

I don't think I have that much room to operate Natal.

Already Posted.

this 4 meter thing was posted before...

(but it was also said that motion controls do take space too...)

also posted, big problem


/thread

Good to know, thanks.

It doesn't need 4 metres , it's just that the full range of it width and height wise will be realised at that distance, unless you're playing a game that requires four people to be spaced out this shouldn't be an issue

I roughly have 2 meters of space between my tv and couch.  If the field of view at 4 meters is 8 feet 10 inches tall, at 2 meters, the vertical field of view is only 4 feet 5 inches and i'm pretty sure i'm taller than that unless I sit down.

There was a thread about this already.  Perhaps this will foster some discussion this time around:

FOV of Natal:

Horizontal FOV = tan(x) = a/b

a = 1/2 of the width.  This is because we are measuring 4 meters from the center point of the lens to the mid point of the slice of space at that distance.  The width of the image at 4 meters distance is 4 meters.  So a = 2 meters.

b = distance from camera to center of image.


tan(x) = 2/4
arctan(0.5) = 26.56 degrees.  We need to double this and get
Horizontal FOV = 53.12 degrees



Vertical FOV = tan(x) = a/b

a = 1.35 meters.
b = 4 meters

tan(x) = 1.35/4
arctan(0.3375) = 18.649 degrees.  We need to double this:
Vertical FOV = 37.298 degrees

XY Accuracy at 4 meters:

Based on the article, at a distance of 4 meters, the dimensions of the detected image is 4000mm x 2700mm.

Given that the sensor in Natal is 640x480, we can determine the distance that 1 pixel represents. 

On the X axis, 1mm = 0.16 pixel.  So 1 pixel = 6.25mm.

On the Y axis, 1mm = 0.17mm.  So 1 pixel = 5.88mm.

XY Accuracy at 2 meters:

Since the dimensions will be linear, we can just divide everything by two.

Dimensions of image = 2000mm x 1350mm

X axis = 1 pixel = 3.125mm

Y axis = 1 pixel = 2.94mm

I do not know how the Z accuracy can be determined since that is based on light intensity of reflected IR, but the only thing we can go by at this point is some specs from a similar product called PrimeSense, which I have listed below.

http://www.primesense.com/category/reference_design

Several things we can use from the specs to make assumptions about Natal.  The Z accuracy at 2 meters is 1cm, so at 4 meters perhaps we can assume it will be 2 cm.  That is with the assumption that it follows a linear function.  The XY accuracy is similar to my calculations.  A maximum distance of 3.5 meters is similar to the stated 4 meter max from the article.  The only big surprise here is that the Vertical field of view is largely different than what I calculated.  37 degrees is rather low for a vertical field of view.  Is there an issue with my methods?  Been a while since I have used any trig stuff.

EDIT:  Just read this bit of clarification:

http://kotaku.com/5500643/japan-relax-about-project-natal

There has been concern in Japan that only gianormous American living rooms are suitable for Microsoft's upcoming motion control peripheral Natal. No need for concern, says Microsoft.

According to website Techflash, "To be precise, you'll want to clear an area extending at least 4 meters (a little more than 13 feet) away from the television."

While it was perceived that a range of 4 meters (over 13 feet) was needed for the Natal to work properly, this is incorrect. "The comments recently about the play space for 'Project Natal' were misinterpreted," Microsoft told Kotaku. "It is true that the 'Project Natal' sensor reads the configuration of your room and adjusts play space, as appropriate. We know that living rooms come in all shapes and sizes, and have conducted numerous play tests to ensure everyone will be able to jump off the couch and into the fun when 'Project Natal' launches globally this holiday."