Generally, calibrations are not required; therefore, most motion detectors don’t support calibration.

Calibrate a Go Direct Motion Detector

Only the Go Direct Motion Detector can be calibrated. A one-point calibration, based on a measured distance, is applied. The new calibration is stored on the sensor.

  • Graphical Analysis/Graphical Analysis Pro—Click or tap the sensor meter and choose Calibrate.
  • LabQuest App—Click or tap the sensor meter and choose Calibrate. (LabQuest 2 and LabQuest 3 only.)
  • Logger Pro—This sensor is not supported in Logger Pro.
  • DataQuest App—This sensor cannot be calibrated using the DataQuest.
  • EasyData—This sensor is not supported in EasyData.

Alternatives to Calibration

It is possible to apply an offset to the motion detector reading as readings can vary based on the interface. Typically, if an offset is needed, it is only 1 or 2 cm. This is similar to a one-point calibration.

  • Graphical Analysis/Graphical Analysis Pro—Use a calculated column to apply a constant offset to all motion detector position readings.
  • LabQuest App—Use a calculated column to apply a constant offset to all motion detector position readings.
  • Logger Pro—Choose Set Up Sensors > Show All Interfaces from the Experiment menu, click the Motion Detector image in DIG 1 or DIG 2, then select Set Offset.
  • DataQuest App—Use a calculated column to apply a constant offset to all motion detector position readings.
  • EasyData App—You cannot easily apply an offset to sensor data in EasyData.

You can zero the motion detector by placing the target at the desired origin, and choosing zero within the software.

  • Graphical Analysis/Graphical Analysis Pro—Click or tap the sensor meter and choose Zero.
  • LabQuest App—Click or tap the sensor meter and choose Zero.
  • Logger Pro—Zero is found in the experiment menu.
  • DataQuest App—Zero is found in Setup Sensors, in the Experiment menu.
  • EasyData App—Zero is in the Setup menu.

The direction of the coordinate system can be reversed so that values increase as a target moves toward the motion detector instead of away.

  • Graphical Analysis/Graphical Analysis Pro—Click or tap the sensor meter and choose Reverse.
  • LabQuest App—Click or tap the sensor meter and choose Reverse.
  • Logger Pro—Choose Set Up Sensors > Show All Interfaces from the Experiment menu, click the Motion Detector image in DIG 1 or DIG 2, then choose Reverse Direction.
  • DataQuest App—Reverse is found in Setup Sensors, in the Experiment menu.
  • EasyData App—Reverse is not supported in EasyData.

Note: Using the combination of Zero and Reverse allows you to do things like measure motion from a point not at the detector. For example, you can point the detector downward toward the floor. Reverse and Zero with nothing between the detector and the floor. Now, the detector will report position above the floor, with up as positive and zero at the floor.

Since the speed of sound is temperature dependent, motion readings will vary slightly by temperature. This is a very small correction, and is almost never important.

  • Graphical Analysis/Graphical Analysis Pro—This is only possible with a Go Direct Motion Detector set up to use the Motion with TC sensor channel.
  • LabQuest App—This is only possible with a Go Direct Motion Detector set up to use the Motion with TC sensor channel.
  • Logger Pro—Choose Set Up Sensors > Show All Interfaces from the Experiment menu, click the Motion Detector image in DIG 1 or DIG 2, then choose Set Temperature. (Note: Temperature compensation is automatic when using a Go!Motion or CBR 2 connected directly via USB.)
  • DataQuest App—This is only possible with a Go Direct Motion Detector set up to use the Motion with TC sensor channel.
  • EasyData App—Temperature compensation is not supported in EasyData.

All motion detectors have a minimum working distance. Make sure your object does not get closer than that minimum distance. These distances are sensor dependent and apply to all software.

  • 15 cm—Go Direct Motion Motion (Cart) sensor channel, Go!Motion, CBR 2, and Motion Detector 2
  • 25 cm—Go Direct Motion Motion and Motion with TC sensor channels
  • 50 cm—Older motion detectors

Additional Information:

Published: March 8, 2018. Updated: May 8, 2024.