Qualisys (QTM)#

mocap4r2_qualisys_driver uses the Qualisys C++ SDK (RT protocol 1.28, MIT license), included in the package.

$ ros2 launch mocap4r2_qualisys_driver qualisys_driver.launch.yaml \
    params_file:=my_qualisys.yaml
$ ros2 mocap4r2 start qualisys_driver

Enable real-time output in QTM (Project options > Real-time output).

Parameters#

Parameter

Default

Meaning

server_address

127.0.0.1

QTM computer

base_port

22222

RT protocol base port

udp_port

0

0: stream over TCP (robust everywhere); > 0: UDP on this port (lower latency)

up_axis

auto

auto reads the up axis of the QTM calibration; or x, -x, y, -y, z, -z

latency

0.0

seconds subtracted from the reception time (QTM does not report its latency)

Data#

  • 6DOF bodies are rigid bodies; untracked bodies (NaN in QTM) are published with tracking_valid: false, never with NaN.

  • Labeled markers keep their QTM label; markers whose label starts with a body name are also attached to that body.

  • Skeletons are streamed in global coordinates with their segment hierarchy.

  • All frames are streamed (RateAllFrames) to a dedicated thread.