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Experiments Using the Accelerometers and the Altimeter
The WDSS was specifically designed for remote data collection at amusement parks
and playgrounds. The three accelerometers can record accelerations in all directions
and, if needed, Logger
Pro
can calculate the net acceleration. The altimeter of the
WDSS can be used to record position on the ride. In general, it does not matter that
the altitude be calibrated well; the altitude data provides a profile of the ride, so you
can know when the high and low points on the ride occurred.
The WDSS can store over 200,000 data points internally. Using a 25 samples per
second collection rate and three accelerometer readings and altitude readings, this
allows for a full forty minutes of data collection. You can do multiple runs before
retrieving the data.
Set up the WDSS for data collection.
1. With the WDSS connected to your computer and running Logger
Pro
, set up the
experiment length, data collection rate, and active sensors. You may want to open
a file we have prepared for amusement park ride data collection. It is found in the
Experiment Files folder/Probes and Sensors/WDSS, and it is named Amusement
Park. It sets up the WDSS to record three axes of acceleration and altitude, and it
calculates net acceleration. Data collection rate is set for 25 points per second for
120 seconds
2. To prepare the WDSS for remote data collection choose /Setup/Remote Data
Collection from the Experiment menu.
3. Select the WDSS. This gives you a dialog box that displays the data collection
parameters so you can confirm that they are set properly.
4. Click OK to set up the WDSS for remote data collection. Note that the Bluetooth
connection LED turns red indicating the WDSS is disconnected and ready to start
remote data collection.
5. At the start of the ride, press the start data collection button on the WDSS. Note
that the Data Collection LED starts blinking green.
6. When the ride ends, press the data collection button again. (If you do not press
this button a second time, data collection will continue until the specified time for
the experiment has expired or the memory of the WDSS is full).
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Many amusement park rides do not require more than one accelerometer. Rides
where the motion is in one direction are the easiest for students to understand. Data
from the Drop Zone amusement park ride, in California is shown below. This a ride
in which the passengers are dropped a distance of about 60 meters and then
decelerated by Lenz’s Law magnetic forces on the falling cars. They always move in
the vertical direction. The lower graph below shows the acceleration. The top graph
is an altitude profile of the motion (data taken with an altimeter).
Data from the Drop Zone amusement park ride
