Setting Up ARFX Free D Tracking Method

Section 8. Setting Up ARFX Free D Tracking Method

FreeD is an open protocol used to track devices, such as cameras, in real-time, over a network. It is widely compatible with systems like Vive Mars, Mo-Sys, Stype, and others. What makes FreeD especially useful in ARFX is that it works seamlessly without Live Link, allowing you to set up tracking either during play or in packaged builds. This flexibility extends to both LAN and internet connections, giving you a wide range of options for virtual production.

As shown in the image, you have two primary options for tracking:

1. SteamVR: This option uses SteamVR to provide the most accurate tracking for compatible pucks or controllers via USB or Bluetooth connections. SteamVR is ideal for those using Vive Trackers connected via USB or Bluetooth dongles. Refer to this section for more details on how you can connect your base station and Vive tracker equipment.

2. Free-D: The Free-D option uses the Free-D protocol to allow trackers like HTC Vive Mars, Mo-Sys, stYpe, Ncam, or even Android/iOS devices to act as hero and calibration trackers over a LAN connection.

Setting up Vive Mars Hardware

The Vive Mars in its promotional shot. Not included: the cables and base stations that are required to make it work.

The ViveMars is an all-in-one package that takes commercially available hardware, usually relegated to VR equipment, into something portable and readily useful for virtual production without the need to set up your machine for the VR environment. It is highly convenient, with the benefits of SteamVR, OpenVR, freeform tracking volumes, and the tools to mitigate the negative effects of such (such as calibrating world origin). It is capable of using both LiveLink and FreeD, and there are addons available that allow for rudimentary LensEmulation.

In ARFX, we are typically only concerned about getting that tracking data to our cameras and there are thankfully some straightforward ways for us to do this.

Important

This section will not cover how to set up the Vive Mars hardware. For that you must refer to its owner's manual.

Recommended Network Setup

For those who are not familiar with setting up local networks, it is highly recommended that you use a DHCP-enabled router to automatically assign unique IP addresses between your computer and the Vive Mars. This router must only be used specifically between your computer and the Vive Mars only, and should not be used as a means for access to the internet.

As most machines of today have two or more ethernet network adapters, you can use both at the same time; one for the internet and the other for tracking only. If using the ARFX StudioBox, it is recommended to free up your ethernet port for the router/switch by connecting your internet ethernet cable using a USB to Ethernet adapter like the following: https://arwall.co/products/uni-usb-c-to-ethernet-adapter or https://arwall.co/products/ugreen-usb-to-ethernet-adapter-1000mbps-ethernet-adapter-with-usb-3-0.

Important

The reason we recommend this is due to security in managed networks like the private networks found in universities and commercial buildings. UDP messaging is required for tracking to work and this messaging protocol may be blocked without administrative changes.

Alternatively, you can try connecting the Vive Mars directly to your host machine, but this may require manually assigning IP addresses to both devices.

How to figure out your machine’s local IP address

A good idea is to unplug everything and connect only one port to figure out which port is which.

The universal way in windows is to figure out your computer’s IP Address is to search for Network Connections in Windows Start Menu. Within the Network Connections menu, there will be a list of connections available to your computer. Find the one used by the connection between your computer and the Vive Mars and double-click it  Details  IPv4 Address to find your IP address for that port.

While you are here, it is highly recommended that you rename your computer’s network adapters to what they are being used for by right-clicking the connection and choosing the Rename option.  If it is for the internet, just name it “Internet Port.” If it is for the Vive Mars, name it “Vive Mars.”

Setting up the Vive Mars

There are two types of tracking the Vive Mars can do: LiveLink and FreeD. However, for those using Vive Mars with ARwall’s Windows App or ARFX Scenepacks, choose the FreeD option.

Please refer to the Vive Mar’s owner’s manual to get yourself familiar with setting up the physical hardware of the Vive Mars.

The Vive Mars’ Network Settings

The main status page of the Vive Mars. Note that everything within the Vive Mars can be done with either its touch screen or a connected mouse and keyboard.

Important

Note the IP address that the Vive Mars will eventually be assigned when it is connected to a valid network. This functions as a button that you can tap to bring up the network page.

The Network page of the Vive Mars. We only really care about the Camera Tracking Protocols section.

Tap Camera Tracking Protocols to bring up the menu we’ve been looking for where you can set up both Live Link and FreeD.

The Camera Tracking Protocols page is where you can set up both Live Link and FreeD.

Be sure the server and the Vive Mars box are both connected to the same switch.

On the Vive Mars box, tap the network box where the network IP address is listed, then tap Camera Tracking Protocols and note the FreeD Port number.

If you are going to use the ARwall’s FreeD Tracking Component or are using our individual packaged scenes, then you may want to use 40000 or 41000.

Important

Once you are done, don’t forget to hit Apply!

Section 8.1 Setting Up FreeD in ARFX Windows App.

1. Launch a scene and open up the ARFX options menu with backslash (\) or ESC button.

2. In the setup section, scroll down to find Free-D Setup.

If the Steam VR option was chosen as the tracking method after login, by default you’ll see the the Steam VR setup under the setup section. You need to choose the Free-D method instead.

3. To choose Free-D as the tracking method, click  the “Select Tracking“ button and choose the Free-D option. Otherwise, if Free-D was chosen during login, proceed with the Free-D setup, as shown in the image below.

3. Set the IP address to the PC's LAN port that is connected to the same network as your Free-D tracking provider.

• You can get this address by using IPConfig in the command prompt.

4. Set the UDP port to either the one provided by the tracking system (if you cannot set it manually) or to a unique number (Default: 41000)

5. On the tracking system, set the IP address to that of the system running the scene and the UDP port you have settled on in Step 4.

• Please refer to your tracking system manual on how to set the FreeD IP address to which the data is being sent.

• FreeD can work across the internet but requires you to do port forwarding on your local network

• Please make sure your firewall will not block the connection!

6. Back on your machine running your scene, press "Start FreeD"

• If the button does not change to "Stop FreeD", you may have either not set the correct IP address for your PC or the port that was set is already in use by another program (such as an Unreal Editor instance).

7. You should get a list of valid trackers below the UDP port.

• If you do not, press Refresh to get it to populate

• If you still do not see anything, you may need to allow the program through your firewall.

8. Finally, set which tracker will be your hero and calibration trackers.

• If you only have one tracker, set it as your hero and enable "Use Hero Tracker as Calibrator"

9. Save your settings and try calibrating!

• Refer to Flipping XYZ Directions if your tracking directions are incorrect.

• Always calibrate in the same direction every time! Depending on what tracking system is used, you may need to mark the tracker in the +X/forward axis

10. Calibration: After configuring the trackers, start the calibration process. Make sure you always calibrate in the same direction for consistent tracking results.

Calibration Using the Vive Mars Trackers

To calibrate ARFX, point the tracker/rover with the USB and ethernet ports facing towards the screen.

Calibration with the Vive Mars Trackers is a little different in comparison to regular SteamVR in that we found that the orientation of the tracker is not flat against the wall, but rather pointing towards the screen as like in the image shown above.