Hardware installation and initial setup

Camera placement

We recommend a room size of approximately 5 x 6 m (minimum 4 x 4 m) and height of at least 2.8 m for the running analysis, with the treadmill located in the center of the room. Other room sizes can also be used but may require different lens types on some or all of the cameras - please contact Qualisys.

Floor and wall coverings should have a matte finish and be non-reflective. Each camera requires a fixed, rigid mounting, usually using a wall bracket that is supplied with each camera.

We recommend that you discuss camera placement, cabling and other building requirements with Qualisys prior to setting up the system.

The standard setup consists of 9 Miqus M3 cameras, 6-7 mounted at a height of approximately 2.6-3 m along each side of the treadmill and the remaining cameras placed lower and towards the front of the runner.

In addition, the standard setup includes two Miqus Video Color cameras. They look similar to the marker cameras but have a different type of LED lights and no IR filter in front of the lens. Typically, one video camera is placed in front of the runner and one to the side.

If only 5 cameras are available, it is still possible to do the analysis. In this case use marker set with clusters and create session called 'Running - Clusters'. Details about marker set and reporting are discussed later.

Camera connections

The camera connections are set up during installation and the cameras remain permanently connected to the computer. Details about the connection can be found in the QTM user manual in the section Making a measurement > Connection of the camera system.

We recommend that the power supply to the cameras is accessible or that the power sockets can be turned on and off with a switch.

Camera settings

Marker cameras

For more details about these settings, please refer to the QTM manual. The following are the default values for the Running Analysis:

Aperture (set manually on lens): closed slightly, usually to the second lowest number.
Focus (set manually on lens): set individually for each camera during installation.
Sensor mode (applies to Oqus 5+ only): 1 MP @ 355 Hz.
Capture rate: recommended 300 Hz, minimum 150 Hz.
Exposure time: 100 µs (may be adjusted during installation).
Marker threshold: 17% (may be adjusted during installation).

To ensure optimal operation of the automatic labeling of markers (AIM), Qualisys recommends the following settings in Project Options > Processing > 3D Tracking:

Prediction error: 30 mm.
Maximum residual: 10 mm.
Minimum trajectory length: 2 frames.
Auto join - Max frame gap: 10

In Project Options > Processing > Trajectories:

Max frame gap: 10, for data with number of small gaps it vcan help to increase it up to 50.

On Project Options > Processing > 3D Tracking:

Define a bounding box to cover a volume just slightly exceeding treadmill size and set the height of bounding box. A height of 2000 mm is usually sufficient.

Miqus video cameras

Typically, one Miqus Video Color camera is placed in front of the runner and one to the side.

Recommended settings are:

Aspect ratio: 4:3
Resolution: 1080p
Capture rate: 100 Hz
Auto white balance: On
Auto exposure: On

If the image is too dark or too bright, it may be adjusted:

By using the Auto Exposure Tool form the 2D Toolbar: draw a rectangle covering the area where the runner will be located. This is useful if you want to exclude a bright window or other light source in the background from the automatic exposure and white balance adjustments.
By using the Exposure Compensation slider.

In small rooms, it can be beneficial to rotate the video camera 90 degrees. To adjust how the video is displayed, start preview in QTM, switch to 2D data and right-click the video camera view to adjust the orientation:

USB web cameras (legacy setup)

Each video camera (USB web cam) can be connected to the computer with a USB extension.

Important: you must use the active USB extension that is provided by Qualisys (Deltaco USB3-1006 Rev 5). Make sure the power supply that is included with the extension is attached to the end of the extension and to a power outlet. Otherwise the web cam may not receive sufficient power.

Follow these steps to set up the cameras correctly:

In QTM project settings, select Input Devices. Check the box for both Logitech HD Pro.
Now the settings for the web cams are available in the AV Devices section. Select each the first webcam (AV Devices > Logitech HD Pro Webcam) and select the line 1920 - 1080 - MJPG - 30 Hz:
Because the Video synchronization is done via Windows it is not always exact. To minimise it, perform a recording of a movement, e.g. clap the hands once. Open the trial, go to the 2D view and right-click the video image. Select Set time offset and play the file. Repeat until the time offset between the videos and the 3D image is acceptable.
After defining the video offsets, these must be added in the following file: [project folder]\Templates\settings.php. Change the value for 'video_1_offset' and 'video_2_offset' to match the settings that are used in QTM.
Also enter the capture frequency in settings.php in the line 'capture_framerate'.

Note: do not use QTM to apply additional compression codecs to the webcam video (via right-click on video preview).

DV cameras (legacy setup)

Each video camera (DV camera) is connected to a separate Blackmagic card on the computer via an HDMI cable.

Please refer to the QTM manual for the detailed camera settings. The standard resolution is 720p at 59.94 Hz. Demo mode and face detection need to be turned off.

In QTM, right-click the video view and set the Video format to HD 720p 59.94. Right-click again, select Choose Video Compressor and set it to ffdshow view encoder. Set up ffdshow as explained in the QTM manual in the chapter "FFDS-MJPEG codec settings".

Computer setup

Usually the Running Performance analysis is delivered as a complete package with computer, hardware and connection cables. The TV screen is not included as it depends on available space. The USB Webcams shown in the following figures are for legacy setups only - as of 2018, the standard setup uses Miqus Video Color cameras for reference video.

The following figures show the connection on the NUC in detail:

Settings backup

When system setup is complete, we recommend that you make a backup of all settings in QTM with File > Settings management > Backup and restore. In case of difficulties you can load this backup.