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Software Configuration - Instruments

 


 

 

 

Calibrate Magnetometer - This section is for calibrating the GPS.

 

Before starting the calibration the helicopter must be prepared.  The calibration process must be done outside as the GPS must initialize and receive signal.  So this means you will need a laptop at the field. 

 

Remember to do this away from vehicles or any magnetic sources.

 

To calibrate the helicopter must be rotated 180° as perfectly as possible. 

 

It does not matter how it is rotated.  It does not matter that the heli rotates on the same spot either. 

 

If any metallic parts are changed, for example the tail shaft, then the whole calibration procedure must be performed again. 

 

To start click "start position".

 

CAPTRON recommends the following:

 

From the manual...

 

 

 

Method A


Ensure that the GPS module is still exactly in its original horizontal position after you have rotated the helicopter. This means: the top surface of the module’s case must lie in the identical plane before and after turning the helicopter. Note that the landing skids are generally not exactly horizontal relative to the helicopter, so a simple flat surface alone is not sufficient.


One simple possibility is to find a horizontal surface by checking with a spirit level, then to level up the GPS module by placing packing pieces under the skids, remembering to check both (imaginary) tilt axes. The skid packing you use must then be attached to the skids before you rotate the helicopter, e.g. using adhesive tape. This procedure ensures that the plane of the GPS module remains unchanged during the calibration process.


Note: simply turning the module itself is not sufficient, because all the metal parts of the model which have to be taken into account must also rotate with the module if the calibration is to be accurate.

 

 

Method B
 

Carry out the calibration using a flat but strongly inclined plane, e.g. a wooden plate packed up on one side: place the helicopter on it and rotate it for the calibration process, without changing the inclination of the plane. Ideally the plane would lie parallel to the Earth’s magnetic lines, which are generally fairly steeply inclined; however, a tilt of 25° to 30° is quite sufficient, with the lowest side facing the closer pole of the Earth. In the Northern hemisphere this means: pack up the South side of the wooden plate. The helicopter is then turned through 180° on the inclined plane. To obtain particularly accurate orientation, the skids should also be packed up as described above.

 

 


 

To use as a "base" I used a large piece of plywood big enough so the width is more than twice the width of the landing gear.

 

I leveled the plywood  using a large ruler with leveling bubble.  Shimmed it using any material readily available.  (such as broken main blades...  :D  )

 

I used the "inclination" display on the instruments tab to assist in finding the perfect level of the helicopter. 

 

 

I used cut out pieces of cardboard to add or subtract the height of one side of the skids.

   

I then wrapped masking tape to secure the cardboard pieces to the skid.

   

I strapped on a laser leveler on the helicopter.  The laser leveler's line acts as the line to reference for the rotation.

   

Turned on the laser and marked the surface with masking tape.

 

I did the calibration at night so it was easy to see the laser light.

   

 

After rotating the helicopter 180° click on "end position".  Done.

 

Also check the "magnetometer signal" display for any magnetic disturbances.  Rotate the main rotor slowly and monitor the display.  If there is movement then the GPS must be moved away further from the motor, servos, etc.

 

 


 

 

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