Assign marker and segment properties

When you have created the skeletal structure and linked all the segments, you can add the marker names and change marker colors and radius, as well as the segment and joint properties of your template. You do this using the controls on the Subjects tab of the Resources pane.

To assign marker names:

1. On the Subjects tab of the Resources pane, expand the node for your subject and select Markers.
   By default, if you have named left and right segments when you created the segments as described in Create segments , markers that are located on the left side of the body are indicated with a red marker icon in the list; markers on the right side are indicated with a green icon. Markers that are neither left nor right are indicated by a gold icon.

   Tip: The distinction between left and right markers is automatically made only if:

   • You have set up the segments to belong to left or right sides as described in Create segments.
   • The model is not unilateral.
   • The segment name begins with Left or Right.
   • The colors defined for the left and right segments are different (as in the default color scheme).
   At this point, the markers have default names that reflect the segment and the order in which they were selected when the segment was created. For example, all markers on the Pelvis will be labeled Pelvis##.
2. Rename each marker to represent its position on the labeling skeleton template, e.g. LASI for Left Anterior Asis. To do this, edit the name in one of the following ways:
   
   • Click a marker name to select it and in the Properties pane below, enter a new name in the Name field; or
   • In the Subjects tree, double-click the marker name or press Enter and overtype it.
     You can then use your keyboard up/down arrow keys to advance to another marker and repeat the process.
   • To ensure that your .vst file complies with the .c3d file format, bear in mind the following points:
     A marker name can contain up to 30 alphanumeric characters (A-Z and 0-9). Do not include any punctuation, spaces, or special characters.
   • The first character of the name must be alphabetical. Subsequent characters can be alphanumeric. For example, LANK1 is permitted, but 1 or L Ankle 1 is not.
   • If the trial contains more than one subject, the subject name automatically prefixes the name you give the label. For example, if you define a marker LASI for a subject named Colin, the full marker label name is Colin:LASI. The sum of the subject and longest marker name must be less than 29 characters.
   For alternative ways to select markers, see Selecting markers.

   Tip: If you selected multiple markers, in the Properties section expand each property, such as Name, by clicking on its plus sign. To save time when renaming, overtype each name and press the Tab key twice to jump to the next field.

3. For each marker, in the Properties pane, edit each marker Color, Radius, and Status as required:
   
   • Color Click on the color bar for a marker. A color picker box opens in which you change the marker color.
     If you are using clusters, you may want to change the color of the cluster markers so that they are easily recognized.
   • Radius Move the slider bar to change the radius of the marker. As you do this, you can see the size of the marker change in the 3D Perspective view.
     To set the radius back to the default size after you have changed it, click the arrow next to the slider bar and select Set to Default.
   • Status Set the marker status to Required, Optional, or Calibration Only.
     If you use markers that are only needed during a calibration trial, it is a good idea to set their status to Calibration Only so that they are not required during movement trials.
     To reset the property to its default, click the arrow to the right of the drop-down box and select Set to Default.
4. If required, reorder the display of markers in the System Resources tree. To do this, right-click the Markers node and then click Reorder. You can then move the markers up or down the Reorder Markers list.
5. On the Subjects tab of the Resources pane, expand the Segments node. Click on one or more segments, and in the Properties pane, change the name and color for these as needed.
6. On the Subjects tab, expand the Joints node. If you want to change the joint names, select one or more joints and in the Properties section, overtype the name(s).
7. Save the custom labeling skeleton template (VST) (see Save a custom labeling skeleton template).
   You can now use your new custom VST to autolabel movement trials (see Calibrate a labeling skeleton in the Vicon Nexus User Guide). However, if you find that this requires a lot of manual correction, you can improve the autolabeling by using the information from a ROM trial to update the custom VST. For more information on how to do this, see Optimize a custom labeling skeleton template.

Selecting markers

You can select markers in any of the following ways:

To select a single marker:

• Click on it in the Subjects tab of the Resources pane; or
• Click on it in the 3D Perspective view

To select multiple markers:

• On the Subjects tab in the Resources pane, drag across multiple markers in the Markers sub node; or
• In a 3D Perspective view, CRTL + click multiple markers