Need coordinates for old Vicon static calibration frame

[Liza Shapiro]

I am using Vicon Motus and need a calibration frame for a (video-based) kinematic experiment on arm swinging in human walking and running. (the only calibration frame I have is tiny, as it was designed for my research on small mammals). Vicon no longer makes human-sized calibration frames for Motus. A colleague of mine at UT had an old Vicon calibration frame from an optical system,but she can't find the data for the coordinates and Vicon can't either (it's from the 90's). I'm attaching a picture - if anyone recognizes this and has coordinate data for it, I would very much appreciate the data! OR, if you have an old Motus calibration frame you are looking to sell, please let me know. Thanks!

Liza Shapiro
Dept of Anthropology
University of Texas at Austin

[Edmund Cramp]

Re: Need coordinates for old Vicon static calibration frame

With a little care and practical geometry you can simply measure the rods and work out the marker locations. The calibration values are simply the co-ordinates of the centroids from the origin. You could also look back through the old calibration data on the original system and probably find a file with the data.

I'd strongly recommend the measurement method first as these types of fixed calibration objects can get a little bent over the years, markers can slip on the rods etc - so even if you find the original calibration positions, you'd still need to check that they are correct.

[Liza Shapiro]

Re: Need coordinates for old Vicon static calibration frame

Thank you - I figured I would end up having to do it manually but thought I'd see what's out there. And that's a good point about markers slipping,etc; I hadn't really considered that. Thanks again,

Liza Shapiro