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Disguise User Guide

Blacktrax Overview

Overview

Setup

Integration

Blacktrax Overview

BlackTrax (BT) is a vision based tracking system available from CAST, capable of tracking both objects and people. Tracking data from BT can be input into and mapped to objects or props within the disguise visualiser.

The BT system uses an array of cameras placed on the stage rig to observe IR markers (small LEDs) placed on the talent or prop. These active markers generate rigid body information that is sent to disguise as they are observed by an array of cameras mounted on the truss/staging. As long as the marker is observable by two cameras an accurate positional fix is possible

The markers are attached to a small BT Beacon unit (usually attached to the talents belt). This unit provides power and control to the IR markers.

BlackTrax can integrate with in two ways:

  • Actor/talent tracking

  • Prop/screen tracking (used for movable scenic pieces)

For additional information and training on using Blacktrax, please visit the CAST website

Setup

Hardware Setup

  1. Plug the BlackTrax server into the switch (using the BTnet Port which is normally port 1)

  2. Plug the Timekeeper and eSync Controller into the network switch. The Timekeeper will also need linking to the eSync with the provided din cable. (This will ensure that all the system works in time)

  3. Plug in the Blacktrax Router into the network switch

  4. Plug in the Charging Station to the network switch (this is not virtual and is only used to configure the beacons)

  5. Install the Blacktrax cameras, these will then need to be linked back to the network switch.

  6. The network switch is a Power Other Ethernet (POE). This means that most of the external hardware will receive its power from the switch.

  7. Once the above is done the BlackTrax hardware is setup. The next section covers how you set up different aspects of the system.

Motive Setup

Motive is the software used to calibrate space and track objects. To set this up, follow these steps:

  1. Select the Aiming layout in the drop down tab.

  2. Select the group and set the camera’s exposure to full.

  3. Set the gain to level 8

  4. Set the image type to High Quality MPEG 4. Now you should be able to see a black and white image from the BlackTrax cameras.

  5. Change the Filter Switching to Visible Spectrum.

  6. To aim the cameras, push the button on the back of the camera this will make the camera view fullscreen and change the image to a High quality Grayscale.

    Now in this mode you should be able to point the camera and get a good quality focus.

  7. Repeat step 5 and 6 for each camera in the BlackTrax system.

At this point the system should be reset to its original state:

  • Exposure: 4000

  • Gain: Medium (4)

  • Image type: Object mode

  • Filter Switching: InfraredFilter

Motive Calibration

The process of calibration is called wanding. See steps below to start the process.

  1. Open the Calibration window in the dropdown tabs.

  2. Once open turn the active marker labeling from true to false (this now sets the system to track a continues IR light source from the wand).

  3. Set the size of your wand.

  4. Select the field labeled “start wanding”; this will then prompt you to save the calibration. Once saved all the cameras will have a red board to show that the process has started.

  5. Plug in and turn on the BlackTrax wand. Move it in a figure 8 motion throughout the space, this should show as sample in the Motive GUI (the software will only sample if it is seen by 3 or more cameras) .

  6. When the system can see a good amount of coverage in all cameras you can tell the Motive system to calibrate the information it has received from the process. Do this by selecting the Calibration field.

    Once done it will score your calibration to let you know if the wanding was poor. If good you can continue to the next step.

  7. The system will now require you to set a ground plane, to do this place the BlackTrax ground plane in the center of your space (what would be 0,0,0) then select the calibrate option.

  8. Turn the active marker labeling back to True once finshed.

Integration

Hardware Setup

Blacktrax Hardware

Positional Data

receives positional information from the BT system at a rate of 100Hz. This data is then used in to move an object or a prop in space.