Quick Start Guide

4/30/2018 PhidgetSpatial 3/3/3 Basic - 1042_0B at Phidgets
https://www.phidgets.com/?tier=3&catid=10&pcid=8&prodid=1025 7/9
When working with an accelerometer it is important to know which is the positive and negative direction on each of the axes. This can be
determined by orienting the accelerometer along each axis and checking the output. The above image shows what the axis readings
should be for each orientation of the 1042.
For more information on how to use the accelerometer, check the Accelerometer Primer.
3-Axis Gyroscope
For more information on the gyroscope, see the Gyroscope Primer.
3-Axis Magnetometer (Compass)
The magnetometer reports the sum of all magnetic fields acting on the 1042. The Earth's magnetic field is only one source that affects this
measurement. In order to get accurate bearing data from the magnetometer ( i.e. to find magnetic north as a compass) any interfering
magnetic effects need to be calibrated out. For more information about calibration, see the section below, or the Compass Primer.
Any magnetic field that is stationary with respect to the 1042, and less than ± 3 Gauss, can be calibrated out of the magnetic field
measurement. This includes both hard and soft iron effects caused by nearby ferrous and magnetic materials. Interfering magnetic fields
that vary in strength and orientation with respect to the 1042 can not be easily calibrated out.
Magnetic field data will become unavailable during every other sample as the compass performs internal calibrations. When this happens,
the magneticField array in the SpatialData structure will either have a length of zero, or each element will equal PUNK_DBL, depending on
the API being used. This needs to be handled explicitly in the event handling code to avoid erroneous program behavior. The maximum
sampling rate of the compass is 125 Hz.
Magnetic Error Correction (Calibration)
In order to get numbers of useful accuracy from the 1042's compass you will need to provide calibration parameters. To make determining
them easy, we distribute a program with our drivers that does this for you.
To calibrate your compass: