Dear BIOMCH-L'ers,

My request is directed at those of you who have a Peak 2D system in
your labs. I have a few questions about the system. I hope this posting
does not qualify as "commercial" in nature. I have already spoken to
Peak, and I simply wish to get some information from those of you who
use the system (for the purpose of objectivity). My questions are:

1. Will the Peak system (2D) compute linear and angular kinematics of the
"segment" (i.e., at the segment centre of mass)? If so, do you know whose
centre of mass proportions are used (Dempster, Clauser, etc.).

2. Is there a limit to the number of markers that can be digitized?

3. When digitizing a grid for scaling purposes, are there limits to the
number of points that can be used?

4. Kinematically speaking, are there any limits to Peak's analysis capab-

5. How well do the system's filtering options work (e.g., can you change
the cutoff frequency of the digital filter to any value, is the filter
a zero-lag filter, etc.)?

Any other information and/or helpful comments you may wish to add
would be most appreciated. Again, I hope that this is an "acceptable"
request, and offer my sincere apologies if it is not. Those of you who
have the system can be of great help to me. Thank you in advance for
your time and your help. If there are enough, I will post a summary of
the replies.


John Barden
Phone: (306) 585-4698
Fax: (306) 585-4854
Address: Faculty of Physical Activity Studies
University of Regina
Regina, Saskatchewan
Canada S4S 0A2