A Virtual Laboratory is not a physical segment in Visual3D but is equivalent to a physical segment to the effect that it has a Segment Coordinate System that can be used to represent the laboratory (or other objects) and has an associated surface model that can be animated as part of the scene. A typical use of the Virtual Laboratory is to represent the floor so that motion capture markers can be projected onto the floor. This can be used for creating Normalized Joint Angles.

For more information please view the Virtual Lab Tutorial.

To create the Virtual Lab segment first create 4 Landmarks: LAB_Origin, LAB_X, LAB_Y, and LAB_Z.

To create Lab_Origin landmark, enter the following into the landmark Tab:

Landmark Name=Lab_Origin Starting Point= leave blank Existing Segment= LAB Offset Using the Following ML/AP/AXIAL Offset ML=0 , AP=0 , AXIAL=0 Calibration Only Landmark=Leave Unchecked To create Lab_X landmark, enter the following into the landmark Tab:

Landmark Name=Lab_X Starting Point=leave blank Existing Segment=LAB Offset Using the Following ML/AP/AXIAL Offset ML=0.1 , AP=0 , AXIAL=0 Calibration Only Landmark=Leave Unchecked To create Lab_Y landmark, enter the following into the landmark Tab:

Landmark Name=Lab_Y Starting Point=leave blank Existing Segment=LAB Offset Using the Following ML/AP/AXIAL Offset ML=0 , AP=0.1 , AXIAL=0 Calibration Only Landmark=Leave Unchecked To create Lab_Z landmark, enter the following into the landmark Tab:

Landmark Name=Lab_Z Starting Point=leave blank Existing Segment=LAB Offset Using the Following ML/AP/AXIAL Offset ML=0 , AP=0 , AXIAL=0.1 Calibration Only Landmark=Leave Unchecked

A subset of 3 of these Landmarks can be used to represent the Segment Coordinate System.

To create the segment, switch to the Segment Tab in model builder mode.

In the Segment Name combo box type Virtual Lab Check the Kinematic Only Check Box Click the Create button In the segment definition dialog, enter the following:

Define Proximal Joint and Radius

Lateral= Joint=Lab_Z Medial= Radius=0.001 Define Distal Joint and Radius

Lateral= Joint= Lab_Origin Medial= Radius=0.001 Extra Target To Define Orientation (if needed)

Location Lateral=Lab_X

Select Tracking Markers
Use Calibration Targets for Tracking Checked Select Build Model

To add a surface model select the Virtual Lab Segment and switch to the Segment Properties Tab. Near the bottom of the dialog, Browse for a Model File and select Apply after the selection.