Advice on Rigid Body design
Posted: Wed Apr 15, 2009 11:42 pm
Hi,
We are trying to track this homegrown head worn display (HWD):
http://farm4.static.flickr.com/3471/336 ... e0b3_b.jpg
(minus the Intersense tracker)
While we have obtained excellent tracking in our lab, we've had a hard time getting acceptable tracking in the actual task domain (military vehicle/cockpit).
We've calibrated it 100's of times (see setup below) and believe we have the best possible calibration under the circumstances. So now we are trying to make the rigid body as good as possible.
Any advice or pictures anyone has on tracking the head with an Optitrack would be very appreciated. Specifically:
- How many markers should we endeavor to have on this HWD?
- I understand we want asymmetric triangles...but how many? -
- Should the triangles be oriented in any particular direction?
-Are we going for a good cross section across each camera's FOV? So this would lead to multiple triangles, facing in orthogonal directions?
-If we use multiple triangles, do these have to be different in scale and leg length? That is can we have a 3cm,4cm,5cm triangle and a 6cm, 8cm, 10cm triangle and be OK? Or once we use a particular combination of leg lengths, do we need to find another asymmetrical combination?
Setup:
Domain: Left seat of turret (left seat) of LAV25
http://data.primeportal.net/apc/arrin_h ... 0hatch.jpg (not our photo, but representative)
Cameras: 8 x VT100 (We actually have 10, but found removing cameras actually helped -- possible by removing IR light that causes mean reflection on all the metal surfaces)
Average distance of camera from head: about 20 in
Camera arrangement: It a tough environment--can't place them exactly where we want to. Basically we have:
2 x cameras on top of vehicle looking down through hatch at head
1x camera in front of head at eye level along line of site
4x cameras off to the right, covering a 30 degree arc
1 camera off to right, perpendicular to user, at waist level
We don't have any cameras off to the left as the vehicle's skin is right off the left shoulder and I'm assuming within the operating envelope.
At them moment, we are using passive markers. We are considering trying active markers and disabling camera illumination.
Thanks
Steve
We are trying to track this homegrown head worn display (HWD):
http://farm4.static.flickr.com/3471/336 ... e0b3_b.jpg
(minus the Intersense tracker)
While we have obtained excellent tracking in our lab, we've had a hard time getting acceptable tracking in the actual task domain (military vehicle/cockpit).
We've calibrated it 100's of times (see setup below) and believe we have the best possible calibration under the circumstances. So now we are trying to make the rigid body as good as possible.
Any advice or pictures anyone has on tracking the head with an Optitrack would be very appreciated. Specifically:
- How many markers should we endeavor to have on this HWD?
- I understand we want asymmetric triangles...but how many? -
- Should the triangles be oriented in any particular direction?
-Are we going for a good cross section across each camera's FOV? So this would lead to multiple triangles, facing in orthogonal directions?
-If we use multiple triangles, do these have to be different in scale and leg length? That is can we have a 3cm,4cm,5cm triangle and a 6cm, 8cm, 10cm triangle and be OK? Or once we use a particular combination of leg lengths, do we need to find another asymmetrical combination?
Setup:
Domain: Left seat of turret (left seat) of LAV25
http://data.primeportal.net/apc/arrin_h ... 0hatch.jpg (not our photo, but representative)
Cameras: 8 x VT100 (We actually have 10, but found removing cameras actually helped -- possible by removing IR light that causes mean reflection on all the metal surfaces)
Average distance of camera from head: about 20 in
Camera arrangement: It a tough environment--can't place them exactly where we want to. Basically we have:
2 x cameras on top of vehicle looking down through hatch at head
1x camera in front of head at eye level along line of site
4x cameras off to the right, covering a 30 degree arc
1 camera off to right, perpendicular to user, at waist level
We don't have any cameras off to the left as the vehicle's skin is right off the left shoulder and I'm assuming within the operating envelope.
At them moment, we are using passive markers. We are considering trying active markers and disabling camera illumination.
Thanks
Steve