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pgagolf
04-16-2007, 12:51 PM
Any suggestions on position tracking with the patriot system? The first three set of numbers come up but they are very small. The orientation is works great and everything has been easy to use for a first time user. What needs to be changed in order to get a bigger distance representation in motion tracking of the sensor?
Thanks!

Gladsomebeast
04-18-2007, 09:29 AM
The Patriot should return the distance the sensors are from the source in meters.

Not sure what is causing your problem. Perhaps the sensors are out of range of the source; try placing the the sensors within .5 meters of the source. You can also use the Patriot PDI manager software to verify the data output of the Patriot.

hosier
04-18-2007, 02:33 PM
I would hazzard a guess that it's not so much a problem as is is a matter of scale.

Since the patriot's distance is reported in meters, the typical maximum is about 1.5 meters. Since the default scale is 1 meter per unit in the vizard world, if you directly attach your object to the tracker, you get at most a 1.5 unit translation. This is why I typically read the data from the tracker into an array and then multiply a scale factor to the xyz component.

There's probably a better way to do this, but it's worked so far.

farshizzo
04-18-2007, 03:04 PM
You can apply a scaling factor to the data when you link it to an object. For example, if you were using the patriot for head tracking you would do the following to scale the movement by a factor of 3:patriot = viz.add('patriot.dls')
link = viz.link(patriot,viz.MainView)
link.postScale([3,3,3],target=viz.LINK_POS_OP) #Scale movement by factor of 3

pgagolf
04-19-2007, 04:42 AM
Thank you!!! Its definitely a scale issue.