reading a c3d file into AB

Hi,

We follow a motion marker system that is different from the the 3 systems AB has. I am trying to upload our c3d file into AB. I searched through the AnyGait forum thread and read this thread

http://forum.anyscript.org/showthread.php?t=3047

However, I am new to AB and some basic setup help on how to load a c3d file with custom marker set and force plate configuration into AB will be helpful.

To start with from my errors, I figured:

(1) The Motion marker names in my c3d and marker.any must match. So I am modifying the marker.any now. However, I have following questions

(a) if I don’t want certain markers can I comment (\) those portions in the marker.any file
(b) Which are the related files I should modify, is it only marker.any
© I see the above thread discussing about the static and dynamic trials file, where do I input these c3d?
(d) We have a total of 6 force plates, how do I specify that to AB. Currently it seems that the ‘forceplate…any’ file has just 4 plates. Can I copy the code 2 more times to create two more force plates? How do I define the orientation /placement of these plates to match our experimental setup, does AB read this from the input c3d?

Is there any help document which has a detailed procedure for this? I have went through the manuals, but I did not find any with information I wanted clearly. Suggestions/recommendations will be helpful.

Thank you
CJ

Hi CJ,

Here are some answers:

We have three mocap based models, here is a quick overview:

  1. MocapModel: This is a generic model for motion capture driven models it is very flexible in terms of model setup
  2. AnyGait: This is a fixed model in terms of marker protocol it requires a static trial to present, if you are using a different protocol than in the model it is hard to change.
  3. AnyMocap: This our newest model which will at some point replace MocapModel, it contains many improvements in terms of ease of use and visual appearance, it would recommend using this model. I can be found here: https://github.com/anybody/anymocap
  1. The Motion marker names in my c3d and marker.any must match. So I am modifying the marker.any now. However, I have following questions

(a) if I don’t want certain markers can I comment (\) those portions in the marker.any file

Yes assuming you are using AnyMocap or MocapModel , this is not possible in AnyGait in this model the marker protocol is locked.

(b) Which are the related files I should modify, is it only marker.any

Yes but for AnyGait it will be much more complex

© I see the above thread discussing about the static and dynamic trials file, where do I input these c3d?

Static trials are not needed in AnyMocap or MocapModel

(d) We have a total of 6 force plates, how do I specify that to AB. Currently it seems that the ‘forceplate…any’ file has just 4 plates. Can I copy the code 2 more times to create two more force plates?

Yes exactly

How do I define the orientation /placement of these plates to match our experimental setup, does AB read this from the input c3d?

yes if the corner nodes are correct this should work automatically

Best regards
Søren