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This page provides guidelines and recommendations to consider when cabling and wiring USB-based and/or Ethernet-based OptiTrack motion capture system.
An Ethernet camera system networks via Ethernet cables. Ethernet-based camera models include Prime series (Prime 13, 13W, 17W, 41) and Slim 13E models. Ethernet cables not only offer faster data transfer rates, but they also provide power over Ethernet to each camera while transferring the data to the host PC. This reduces amount of required cables and simplifies the overall setup. Furthermore, Ethernet cables have much longer length capability (up to 100m), allowing the systems to cover large volumes.
Ethernet cameras connect to the host computer through a Gigabit (1000 Mb/second) Ethernet port. Note: the camera network should be segmented from the office or other local area networks to avoid interference and congestion. If the computer used for capture is connected to an existing network, then a second Ethernet port or add-on network card can be used to connect the camera network. When the camera network is not isolated, frame drops may occur.
Note: Turn off your computer's firewall for the particular network in order to connect the camera network to the host PC.
OptiTrack’s Ethernet cameras require PoE or PoE+ Gigabit Ethernet switches, depending on the camera's power requirement. The switch serves two functions: transfer camera data to a host PC, and supply power to each camera over the Ethernet cable (PoE). The switch must provide consistent power to every port simultaneously in order to power each camera. Standard PoE switches must provide a full 15.4 watts to every port simultaneously. Prime 17W and Prime 41 cameras have stronger IR strobes which require higher power for the maximum performance. In this case, these cameras need to be routed through PoE+ switches that provide a full 30 watts of power to each port simultaneously. Note that PoE Midspan devices or power injectors are not suitable for Ethernet camera systems.
The eSync is used to enable synchronization and timecode in Ethernet-based mocap systems. Only one device is needed per system, and it enables you to link the system to almost any signal source. It has multiple synchronization ports which allow integrating external signals from other devices. When an eSync is used, it is considered as the master in the synchronization chain.
With large camera system setups, we recommend connecting the eSync onto the aggregator switch for more stable camera synchronization. If PoE is not supported on the aggregator switch, the sync hub will need to be powered separately from a power outlet.
If the number of cameras included in the system exceeds the number of ports available from the switch, a star topology setup with an uplink switch connecting subsequent switches will be required. In this case, large amounts of data will be transferred through the uplink switch. In order to cope high bandwidth, it is recommended use the 10 Gigabit uplink switch and connect to the host PC with a 10 Gigabit cable – Cat6a, Cat6e, and Cat7. Otherwise, system latency can increase and frame drops may occur.
Notes on USB camera models
At this point, all of the connected cameras will be listed on the Devices pane and the 3D viewport when you start up Motive. Check to make sure all of the connected cameras are properly listed in Motive.
Then, open up the Status Log panel and check there are no 2D frame drops. You may see a few frame drops when booting up the system or when switching between Live and Edit modes; however, this should only occur just momentarily. If the system continues to drop 2D frames, it indicates there is a problem with how the system is delivering the camera data. Please refer to the troubleshooting section for more details.
› Q : Which camera models can be used together in the same system?
A: OptiTrack camera models can be categorized by their connector cable types: USB and Ethernet. Generally, cameras sharing the same cable type and sync mode can operate together within the same system, with the Flex 13 being the only exception. Flex 13 models have a different timing mechanism compared to other USB camera models. Therefore, they are not cross compatible with other USB cameras. Below are some considerations that should be made when incorporating different camera models simultaneously.
› Q : [Ethernet Cameras] Prime series, or Slim13E, cameras dropping 2D frames.
A: 2D frame drops are logged under the Status Log and it can also be seen in the Devices pane. It will be indicated with a warning sign () next to the corresponding camera. You may see a few frame drops when booting up the system or when switching between Live and Edit modes; however, this should occur only momentarily. If the system continues to drop 2D frames, it means there is a problem with receiving the camera data. In many cases, this occurs due to networking problems.
To narrow down the issue, you would want to disable the real-time reconstruction and check if the frames are still dropping. If it stops, the problem is associated with either software configurations or CPU processing. If it continues to drop, then the problem could be narrowed down to the network configuration, which may be resolved by doing the following:
› Q : [Ethernet cameras] Cameras not detected at all.
A: If you have all of the cameras connected as instructed and cameras are still not showing up in Motive. Run ipconfig on command window and check if an IPv4 IP is assigned to the network adapter that connects to the camera switch. If no IP is assigned, check the following:
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