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= What is the VibrationTest Tool? =

The tool evaluates the vibration generated by the motors which allows balancing motor/prop assemblies and experimenting with different motor-mounts. The test uses the MK build-in sensors, so no extra hardware is required.

Reducing vibration is very important, especially for Aerial Photography or Video. Vibrations result in blurry footage. Some claim that high frequency vibrations can be picked up by the Optical Image Stabilization lens assembly which is incorporated in almost all recent cameras. The OIS is not designed for these vibrations and makes thing worse, even when you switch the OIS feature off in the camera menu.

In addition, the FlightControl sensors pickup the vibrations and this deteriorates performance; the new FC ME comes with vibration dampers in order to reduce the vibrations transferred to the FC.

Propellers can be balanced the traditional way. However it was discovered that also the motors need balancing. One way to accomplish this is let a small unbalance in the prop compensate the motor unbalance, so the orientation of the prop is important (see [http://www.rcgroups.com/forums/showpost.php?p=12832508&postcount=228 this post]). Looking at the vibraions of a running motor allows balancing the prop/motor assembly as a whole.

= How does it work? =

The standard FlightControl program samples all sensors periodically and provides a command to read the latest sample from all sensors. The MKTool uses this command to generate graphs of the analog values. In a first approach the VibrationTest used this standard command to monitor vibrations. The problem is that this mechanism only allows to sample the values 30 times a second. The actual shape of the signals cannot be determined and one can only hope to catch the peak values. In order to get reliable results the values need to be monitored for a long time (a minute for example).

This new approach is based on dedicated FlightControl software providing a new command. The new command instructs the FC to sample one of the sensors as fast as possible and store the info in its internal memory. Afterwards the recorded data can be read to analysis. This allows to grab a reliable signal in a very short time. This approach can capture about 11000 samples a second, 500 times more than the MKTool can.

This is an example of the signal measured by the Roll-ACC sensor:

[[Anchor(SampleSignalJpg)]]

attachment:test.jpg

= Current Project status =

/!\ ~+'''The version available now (version 0.9) is an beta version; it was only tested by a limited amount of people.

[[BR]]More testers/evaluators are very welcome!'''+~

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At the time of writing, the tool was tested in combination with:

 * PC/Windows XP and Vista

 * FC 1.2 and FC 1.3

Theoretically the tool should also run on MAC and Linux.

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Features in the pipeline

 * Automatic backup and restore of flight settings

 * Automatic installing and restore of RC flight code

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{i} [http://forum.mikrokopter.de/topic-11446.html MK Forum thread for discussions]

[[BR]]

{i} [[MailTo(frederic AT rc-flight DOT be)]]

= How do I install the tool? =

The tool is written in programming language called [http://en.wikipedia.org/wiki/Python_(programming_language) Python].

The most logic way to run the tool is to install support for Python on your PC (if you do not have it already) and the Python libraries the tool depends on.

Python is also available for Linux and MAC; the tool should also run on these platforms, but I have never tried it.

If you do not feel like installing Python, a version that is compiled to a windows executable is provided.

So, you have two options.

[[Anchor(InstallPython)]]

== Option 1: Install Python ==

For a Windows machine I propose you install:

 * [http://www.activestate.com/activepython/ ActivePython for Windows] Press the big "ActivePython Download Now" button.

 * [http://sourceforge.net/projects/pyserial/files/ PySerial (support for serial port access)] Select "pyserial-2.5-rc1.win32.exe" on that page.

 * [http://www.wxpython.org/download.php wxPython wxWidgets for Python] Select the the win32-unicode version for Python 2.6

 * [http://sourceforge.net/projects/numpy/ NumPy, the fundamental package needed for scientific computing with Python]

Once you have Python support on your PC, unzip [http://www.rc-flight.be/VibrationTest/VibrationTest_0_9.zip VibrationTest_0_9.zip] to a directory on your PC.

== Option 2: Get the compiled version ==

unzip [http://www.rc-flight.be/VibrationTest/VibrationTestExe_0_9.zip VibrationTestExe_0_9.zip] to a directory on your PC

= How do I use the tool? =

== Prepare your MK ==

=== Secure your MK ===

I use luggage straps to secure my MK to the table while it is still able to vibrate:

attachment:mk1InTest.jpg

=== Installing the FlightControl software ===

The VibrationTest tool only works in combination with a special version of the FlightControl software. It must be flashed in the FC board before using the test and '''you need to reinstall your regular software version afterwards'''. This just takes a few minutes. Switching the software is done the usual way, using the MKTool.

You will find the required hex file in the same directory with the VibrationTest tool.

/!\ '''The FC code for the VibrationTest is based 0.74d but is not fit for flying! Before flying, you will need to reinstall your initial FC code. When the version you use for flying is 0.74d, your settings should be preserved. In combination with other versions, it might not be the case. It is a good idea to backup yout settings to PC (via the MKTool) before installing the VibrationTest FC code. '''

After insatlling the FC code for the VibrationTest, the LC-Display in the MKTool will look like this:

attachment:LCDisplay.jpg

== Starting the VibrationTest tool ==

In the directory where you unzipped the tool, dubbleclick VibrationTestGui.py (in case of the Python version) or VibrationTestGui.exe

== Using the VibrationTest tool ==

/!\ '''This video needs updating as it does not use the latest version of the VibrationTool''' /!\

[[Vimeo(6948282)]]

== Balancing Examples ==

[[Vimeo(7011506)]]

= Links =

 * [http://forum.mikrokopter.de/topic-11446.html MK Forum thread for discussions]

 * [http://svn.mikrokopter.de/mikrowebsvn/listing.php?repname=Projects&path=/VibrationTest/#_VibrationTest_ VibrationTest Project in Subversion]

 * [http://www.rcgroups.com/forums/showthread.php?t=1006721 Old Man Mike "Test Fixture Evaluates Motors/Props/ESCs for Quadcopter Performance"]

 * Mail FredericG: [[MailTo(frederic AT rc-flight DOT be)]]

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## [[AttachList]]

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 . KategorieTools