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Measurement probe tool utilizes the precise tracking of OptiTrack mocap systems and allows you to measure 3D locations within a capture volume. A probe with an attached rigid body is included with the purchased measurement kit. By looking at the markers on the rigid body, Motive calculates a precise x-y-z location of the probe tip, and it allows you to collect 3D samples in real-time with sub-millimeter accuracy. For the most precise calculation, probe calibration process is required. Once the probe is calibrated, it can be used to sample single points or multiple samples to compute distance or the angle between sampled 3D coordinates.
Measurement kit includes:
Custom Probes
Caution
You can also use the probe samples to reorient the coordinate axis of the capture volume. The set origin button will position the coordinate space origin at the tip of the probe. And the set orientation option will reorient the capture space by referencing to three sample points.
As the samples are collected, their coordinate data gets written into a CSV file (measurement.csv) in the OptiTrack folder in the Documents directory. Each time a sample is collected, a new line will be written in the CSV file with the information on the 3D positions of the collected measurements and the respective RMSE error values. A new header will be created when the take samples are cleared from Motive and a new sample is collected. If the OptiTrack folder doesn't exist in the documents directory, it may fail to output the csv file. Please make sure "OptiTrack" folder is in the documents directory.
Please check the following directory for the measurement.csv file:
Location of the probe tip can also be streamed into another application in real-time. You can do this by data-streaming the probe rigid body position via NatNet. Once calibrated, the pivot point of the rigid body gets positioned precisely at the tip of the probe. The location of a pivot point is represented by corresponding rigid body x-y-z position, and it can be referenced to find out where the probe tip is located.