Rotary Motion Sensor

Rotary Motion Sensors measure measure the rotation of a wheel either as a distance traveled or as rotations. Newer Rotary Motion Sensors are auto-ID when used with LabQuest or LabQuest Mini. If you have a Rotary Motion Sensor that is not auto-ID or you are using a different interface, it must be set up manually. The easiest place to get started is to use one of the experiment files that comes with Logger Pro. These files were set up to cover the most common experiments using a Rotary Motion Sensor.

Using Rotary Motion Sensor Experiment Files

  1. Connect the interface to a computer running Logger Pro.
  2. Connect the Rotary Motion Sensor to a DIG or DIG/SONIC port on the interface.
  3. Open an experiment file. To do this, choose Open from the File menu; choose Probes & Sensors, then choose Rotary Motion Sensor.
  4. Browse through the files to find one that best covers the experiment you are conducting. The files with "high-res" in the title are set up so the angular resolution is increased by a factor of 4. However, the maximum data-collection rate is decreased by a factor of 4.

If you do not find a file that will work for you, see below for tips on manually setting up a Rotary Motion Sensor.

Manually Set Up a Rotary Motion Sensor

  1. Connect the interface to a computer running Logger Pro.
  2. Connect the Rotary Motion Sensor to the digital port of your interface (DIG 1 or 2 on LabQuest, DIG/SONIC 1 or 2 on LabPro).
  3. Choose Set Up Sensors from the Experiment menu.
  4. Click the Rotary Motion Sensor in the list and move it to the correct digital port.
  5. Once the Rotary Motion Sensor is set up, the sensor status will be shown. The position is in millimeters. The status of the Rotary Motion Sensor is also displayed under the toolbar. A Zero button will also be added to the toolbar

Rotary Motion Sensor Settings

After setting up your Rotary Motion Sensor, you can make changes to the setup by choosing Set Up Sensors from the Experiment menu. Click the Rotary Motion Sensor in the appropriate channel box in the Sensor Setup window to change the settings. See below for information about the available set up options.

Sensor Info

Select Sensor Info to access the Sensor Settings dialog. On the Equation tab, the following settings can be changed.

Current Calibration

Change the calibration between Position (measures translation using the circumference of the pulley wheel) and Angular (Measures angular position of sensor shaft) and select Units.

Counts/rotation

Selecting 360 means that one count is given for each full rotation.

Diameter

Enter the diameter of the wheel (only available when Position is selected as the Calibration).

X4 Mode

In X4 mode, the angular resolution is increased by a factor of 4. Please note that to achieve this resolution, the maximum data collection rate is decreased by a factor of 4, as well.

Reset on Collect

Toggles automatic zeroing of position and angle variables when data collection is initiated.

Current Units

Choose between degrees, revolutions, and radians.