Before you create a new labeling skeleton template (VST), design your marker set so that the labeled markers will give the information that is required for your work. For example, if you are creating a new VST because you are designing a new biomechanical model (which you can produce using Vicon BodyLanguage, MATLAB, Python, or Vicon ProCalc), you must make sure that the labeled 3D marker positions will be enough, or more than enough, to calculate all the required joint centers and segment orientations.
This step is very important, because all the subsequent work you do in Vicon Nexus depends on you having initially identified a comprehensive marker set. The main purpose of setting up a labeling skeleton template in Nexus is to provide automatically labeled markers, so Nexus can process your data quickly and easily after capturing trials.
Vicon recommends that you create a full list of the markers required for your particular experiment, the labels that these markers will have, and which markers, if any, are only required for a static trial.
Tips for designing a marker set
- In addition to preparing a list of markers, consider attaching markers to a subject and viewing them in the capture volume as part of the design process.
- Aim to have at least three markers for each required segment: two markers will give a line, but three markers will enable the calculation of a plane.
- Place markers on known anatomical landmarks to ensure repeatability between subjects.
- When you create your marker set, it is often useful for your biomechanical model to have markers placed on joint axes. However, for the most efficient labeling, avoid sharing markers between segments.
- If possible, avoid placing markers where they will be subject to unwanted movement (for example, on soft tissue), and/or where they will be occluded by the subject's movement during movement trials.
After you have finished designing your marker set, you must create an empty subject in which to configure the template.