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Vicon Nexus

A few notes on using Vicon Nexus for biomechanics.

Good Practice

Subject Preparation

  1. pick the session where you have the cleanest set of markers
  2. create a new subject from the full-body plugin-gait template
  3. if you lack markers, detach them from the marker set in the subject you just created
  4. enter subject mass in the subject properties
  5. don’t forget to save your subject!

Subject Calibration

  1. pick the cleanest trial: ideally it should have something like a t-pose, or close, then find the best frame.
  2. you might want to try auto-labeling here, but it never really worked for me
  3. if auto-labeling fails, manually label the markers in this frame
  4. select the “plugin-gait” static pipeline, check the “processing static subject calibration”, and run it
  5. save your subject!

Auto-Labeling

  1. in the data-management plane, mark all the trials in this session
  2. in the batch processing toolbox, run the reconstruct and label
  3. you may also want to run the “auto-intelligent gap fill” if your captures were a bit messy

Region of Interest

  1. for each capture, adjust the region of interest, right click and “zoom to region of interest”
  2. save the trial
  3. cleanup the remaining artifacts (fill gaps, etc…)

Other Sessions

note: this assumes a (reasonable) subset of the markers used in the cleanest session

  1. load the subject file from the previous (cleanest) session
  2. save the subject
  3. select all the trials in this session
  4. run the “reconstruct and label”, then “auto-intelligent gap-fil”

Trajectory Swap

sometimes the labeling is confused and two trajectories swap with each other each time you try to label one. in this case, switch labeling mode to “forward/backward” instead of “whole” and fill the gap.

Missing Markers

I MESSED UP! WAT DO?!?!!