---
title: "Optimize a custom labeling skeleton template"
canonical: "https://help.vicon.com/space/Nexus215/11371246/Optimize%20a%20custom%20labeling%20skeleton%20template"
format: markdown
---
When you created your custom labeling skeleton template, you captured a static trial (see [Capture and reconstruct the marker set](https://vicon-help.atlassian.net/wiki/spaces/Nexus215/pages/11378961)). Static trials are easier to work with than movement or ROM trials when using the Nexus skeleton-building workflow (see [Create the skeletal structure](https://vicon-help.atlassian.net/wiki/spaces/Nexus215/pages/11372559)). However, a static trial does not produce skeleton parameters that are likely to be representative of the movements to be captured in the dynamic trial, so it may not produce the best labeling. To improve labeling, you can provide more representative data by capturing and calibrating a movement or ROM trial. Nexus can then use the data from the movement or ROM trial to update the labeling skeleton template (VST).

**To optimize a custom ****VST****:**

1. Capture a ROM trial. To do this:
  1. With Nexus in **Live** mode, in the **Subject Preparation** pane > Macro (inline-media-image)

, click **Start** in the **Subject Capture** section.   
The **Start** button label changes to **Stop**.
  2. Have the subject hold the base pose for one second and then move the segments within the VST through as full a joint range as possible. To produce the best calibration and auto-labeling, ensure that each joint is moved through a range that represents the movement that is likely to be captured during movement trials.
  3. Click **Stop** to finish the capture.
2. Attach your custom skeleton labeling template (VST) to your subject (see  [Create a new subject from a template](https://vicon-help.atlassian.net/wiki/spaces/Nexus215/pages/11375036) in the *Vicon Nexus User Guide*).
3. Reconstruct and label the ROM trial, using the **Reconstruct and Label** pipeline, and manually label markers as necessary (ie, if markers become unlabeled). Do not perform any gap filling.
4. To calibrate the ROM trial, run a **Calibrate Labeling Skeleton ROM** pipeline. This pipeline optimizes the skeleton parameters used for autolabeling, including joint and marker positions for the whole trial, and calculates joint and marker statistics. If you have any calibration-only markers, before running the pipeline, select **Functional Skeleton Calibration **from its operations list. Open its Advanced properties and make sure **Remove Calibration Markers** is cleared.
5. After you have run this pipeline, you must update the VST to match the data that was calculated for this specific subject (VSK) during the ROM trial. To do this, double-click the **Update Skeleton Parameters** operation. Before running the operation, in its Advanced properties, ensure that **Update Parameters** is selected.
6. To set the pose used for autolabeling the static frame in future trials, choose a frame in which the subject is standing in the desired pose and, also in the **Pipeline Tools** pane, under **Subject Calibration**, select and run the **Set Autolabel Pose** pipeline operation. To check the pose is correct, you can change the view type from **3D Perspective** to **Subject Viewer**.

You can now save the custom VST (see [Save a custom labeling skeleton template](https://vicon-help.atlassian.net/wiki/spaces/Nexus215/pages/11381463)).