View Full Version : 3D Calibration

A.w. Smith
02-27-1995, 03:24 AM
Dear BIOMCH-L Readers,

We have recently purchased a system for collecting and
analysing video-based 3D kinematics. Previous to this,
our analyses were 2D using an in-house system developed
over the past 7-8 years. Now, we need to get up to speed
with 3D and to do this we need to obtain/build a calibration

I am somewhat familiar with the rigid-type cubes (such as
the WATSMART calibration cube) and the non-rigid types
(such as the Motion Analysis Corp.'s Elite System which
uses balls suspended on thin nylon lines).

I would be very much interested in other user's more creative
(read: "inexpensive") solutions regarding 3D calibration.
What are the pros/cons of the rigid- versus non-rigid-designs?
What are the "typical" number of points you are using? What
materials did you use in constructing your cube? If your lab
is as space-starved as ours, do you have a problem with
storage of the cube? Can the cube be of a collapsible or
folding design and still be accurate? Where would be best
place to get a 'home-made' cube surveyed?

I am also aware of other tree-like designs and I would welcome
any input from users of this type of calibration object.
Any input would be appreciated. I will post any non-commercial
replies (I will keep any replies from companies and readers
who are interested in these can email me directly).


Drew Smith, PhD

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