User Manual
Slam Stick User Manual
Version No. 2.0
31
software. These polynomials are also the required equations for exporting raw Slam Stick data
into another analysis software, such as Python or MATLAB (See Exporting Data for more
information on exporting data to MATLAB or Python).
The ‘User Calibration’ tab located next to the ‘Factory Calibration’ tab can be used to generate
new calibration polynomials for a Slam Stick if the device measurements begin to drift from the
factory calibration values. Proper procedure for performing a user calibration on a Slam Stick is
listed below.
NOTE:
This tool is only to be used if a user is familiar with calibration procedures of an
accelerometer and feels comfortable performing a calibration procedure with a Slam
Stick. For details on Midé’s factory calibration method, see the Calibration section of this
user manual.
1.
In the event that an accelerometer offset has drifted away from its calibrated value, or
the coefficients of the calibration polynomials saved to the Slam Stick device are
inaccurate according to the actual device measurements, a user calibration can be
performed to ensure the device continues recording accurately by using the Slam Stick
Lab software.
2.
To access the user calibration information, first select the “Device” pulldown menu and
select “Configure Device” just as you would to configure the sampling rate, setup a trigger,
or view device information. Select the device you wish to adjust the calibration for, click
“OK” and enter the configuration window as shown below.
3.
Click the “Create User Calibration” button after selecting the “User Calibration” tab at the
top of the configuration window. This will display the current calibration information for
all channels of the device (Analog accelerometer: X, Y, Z; DC Accelerometer (If Applicable):
X, Y, Z; Temperature; Pressure; ADC) and allows the user to edit each calibration value by
clicking “Edit”. (See Below)
4.
The important information to identify are the coefficients for each channel of the device.
The first coefficient for the DC accelerometer (X, Y, Z channels) will correspond to the gain
associated with the measurement in that channel. The second coefficient of the DC
accelerometer channels refers to the offset detected by the device when no applied
vibration is present and the accuracy of this offset can be determined by the user.
5.
In order to verify that the coefficients are configured correctly for the DC accelerometer
channels and the analog accelerometer channels, configure the sampling rate for the DC
accelerometer to 3200 Hz (5000 Hz for the analog accelerometer) and place the Slam Stick
on a level surface (Z axis facing towards the ceiling); take a recording for 10 seconds
without generating any external vibrations. Stop the recording and open the data file in
the Slam Stick Lab. With the DC channel tab selected in the viewing window (The second
Accelerometer tab), observe the value recorded for the X axis and Y axis in the data (i.e.
