Additional Nexus reference PDFs:

Nexus legacy documentation:



Nexus PDFs

Dikablis Eye Tracker node

The Dikablis Eye Tracker enables you to track movement of the eye's pupil to calculate the gaze vector. Its node is displayed under the Devices node when Vicon Nexus is connected to a Vicon system that includes at least one Dikablis Eye Tracker.

The Dikablis Eye Tracking system is compatible with current Vicon cameras. A minimum of two cameras are required for use with the system.

For information on setting up a Vicon system that includes Dikablis Eye Tracker, see Eye tracking with Vicon Nexus.

Dikablis Eye Tracker node context menu

The following command is available from the context menu that is displayed when you right-click on a Dikablis Eye Tracker node in the resources tree on the System tab:

Command

Description

Remove Device

Removes the Dikablis Eye Tracker node from the System resource tree.

Dikablis Eye Tracker node properties

You can configure the following settings in the Properties pane for a Dikablis Eye Tracker. For instructions on setting up the hardware, see the Dikablis Eye Tracker User Manual.

General section

Property

Description

Name

A user-defined display name for the device.
Default: Blank

Delay Compensation (s)

The delay compensation value (in seconds).
Many eye tracking systems, particularly new wireless systems, may introduce a small delay in transmission of data. This delay may cause a misalignment between Vicon frames of data and eye tracking frames of data. The Delayed Compensation slider bar enables you to correct this difference and properly align Vicon data with eye tracking data. To find the amount of delay for an eye tracking system, refer to the operating manual of the eye tracking system.
All devices have a delay compensation value which adjusts the synchronization offset between the device and the Vicon data. Analog data collected with the Vicon connectivity devices should already be synchronized, so this value should be set at 0. Values can be set between -10 and 10.
Default: 0

Head Segment

Enter or navigate to the name of the segment that contains the eye.

Connection section

Property

Description

IP Address

Enter the same IP address that has been set in the Dikablis Recorder software.

Port Number

The port number for connecting the Dikablis Recorder on the Dikablis laptop. Normally, leave this number at its default value (2002).

Eye Offset section

To find the relevant eye offset values, if your Vicon system includes video cameras, you can use overlay video. If not, you can measure the distance from the origin marker.

Property

Description

x

Enter the X-coordinate of the eye in the head segment coordinate frame (the distance between the origin marker and the eye (in mm)

y

Enter the Y-coordinate of the eye in the head segment coordinate frame (the distance between the origin marker and the eye (in mm)

z

Enter the Z-coordinate of the eye in the head segment coordinate frame (the distance between the origin marker and the eye (in mm)

Calibration section

Property

Description

Calibration Object

Enter the name of the calibration device (normally Wand)

Reset

Clears the current calibration

Add

Add a point to the current calibration.

Remove

Undoes the last Add operation

Samples

The number of points used in the current calibration

Residual

Estimated residual accuracy value. Calculated as the average reprojection error in eye tracker pixels.