Setup TRACKPixx3

To setup a TRACKPixx3 within LabMaestro, confirm that the DATAPixx3 and TRACKPixx3 are detected and added to the project. Refer to Adding VPixx Hardware to a project for more information.
This page assumes that the TRACKPixx3 installation has been completed and that users are familiar with its operation principles. Relevant documentation can be found here Principles of TRACKPixx3 operation.

Navigating to the Configure TRACKPixx Properties

Once the desired DATAPixx3 and TRACKPixx3 required project settings TRACKPixx3 Device Settings have been set and applied to the device, click on:

Configure TRACKPixx Properties

The configure tracker properties are expected to be reviewed and modified on a subject-to-subject basis before launching an experiment, and are neither persistent across LabMaestro sessions, nor saved in LabMaestro Projects Files (*.lm) .

ConsoleOverlay: When a 27" monitor is connected to the "DisplayPort Out 2" port on the DATAPixx3, ConsoleOverlay determines the format of both the stimulus display and TRACKPixx3 camera passthrough view. There are four different views available:

FullStimuliNoTracker: Default view.
FullStimuliHalfTracker: Recommended view with a TRACKPixx3.
HalfStimuliFullTracker: Provides a larger TRACKPixx3 camera view than the FullStimuliHalfTracker.
FullStimuliHalftTracker: Both stimuli and TRACKPixx3 camera views are maximized on the console display.

Distance: The distance, in cm, between the TRACKPixx3 camera and the eyes of the participant. In tabletop TRACKPixx3 setups, this distance is often 60 cm.

FixationDetection: Sets the arguments required to generate online fixation flags. Two arguments need to be set:

Max Speed: This is the threshold required for fixation detection, in degrees of visual angle (dva/s). A 30 dva/s threshold is recommended for initial setup.
Duration: This determines how long the fixation speed must remain below the MaxSpeed threshold before generating the fixation flag, in seconds. This value must be a multiple of 1/2000. A 0.005 s value is recommended for initial setup.

SaccadeDetection: Sets the arguments required to generate online saccade flags. Two arguments need to be set:

MinSpeed: This is the threshold required for saccade detection, in degrees of visual angle (dva/s). A 30 dva/s threshold is recommended for initial setup.
Duration: This determines how long the fixation speed must remain above the MinSpeed threshold before generating the fixation flag, in seconds. This value must be a multiple of 1/2000. A 0.005 s value is recommended for initial setup.

Infrared Intensity: Set an infrared illuminator intensity. Lowering the IR intensity (or reducing the TRACKPixx3 aperture) might improve eye-tracking quality when spurious corneal reflections are generated on the cornea.

Species optimizations:

Human. Standard settings and algorithms for human participants. The infrared intensity selection range is constrained between 0-8 .
Non-human primates. Compared to the standard human mode, increases the range of allowable infrared intensity from the illuminator and relaxes a constraint on detected pupil size relative to iris width. This mode may improve tracking with non-human primates and should not be used with human participants.

Gaze vector mode:

Pupil with corneal reflection. Standard gaze algorithm which computes a vector between the center of the pupil and the corneal reflection detected on the eye image, below the pupil. This mode requires that participants use head-restriction hardware such as a chinrest.
Corneal reflection only. The gaze algorithm computes a vector between the camera image origin and the corneal reflection. The pupil is completely ignored in the gaze-tracking algorithm. Recommend systematic use of search limits. This mode is very sensitive to small head movements and should only be used with head-restriction hardware which provides exceptional head stability.

Configure the TRACKPixx3

Once your device settings are set, you can further configure settings to optimize data collection on a participant-by-participant basis. To access these settings:

On the toolbar in the top of the LabMaestro window, press Configure TRACKPixx.

Press Wake TRACKPixx

You should now see a contextual window open in the center of the LabMaestro interface. From here, you can adjust the following settings: