This project was started in , electronics and control loops. Because I always need a cool project to learn new things, it was clear that something that can fly had to be built.
The project started as a "tricopter-only" project, but as I wanted to build smaller vehicles with more payload capacity, I decided to make some quadrotor, hexacopter and Y6 hexacopter firmwares too. My main interest is to build very small MAVs that fly as good as larger ones (or even better) and that can be controlled by wireless video link. I also experimented with autonomous flight in GPS-denied areas (video), and with GPS assisted autonomous hover (video).
-- William

Contact: Shrediquette @ g m x . d e --- All content published under CC Attribution-Noncommercial-Share Alike 3.0 Germany

Shrediquette with IMU 6DOF Razor - Ultra-Thin IMU

Sven - a friend of mine - built his Shrediquette using the cheap IMU 6DOF Razor - Ultra-Thin IMU. Some modifications have to be done, because the gyros and accelerometers on this IMU work with 3.3V instead of 5V:

You will also need to modify the source code, because the arduino needs an external 3.3V reference for the ADC. Modify this line to change from AVCC to AREF:

'===ADC SETTINGS===
Config Adc = Single , Prescaler = Auto , Reference = Aref   'reference is changed from AVCC to external reference AREF


The source code for an external reference: Tricopter_m328p_11_external_reference.zip

Here is a video of Sven's Shrediquette. I also had the opportunity to test it in flight, and it flies really good.



The only drawback is the IMU's sensitivity to vibration, so you really have to make sure that vibrations are generally low. This is how Sven tried to dampen the IMU:
If you have questions regarding this mod, please contact Sven (email is in the pictures above).

4 comments:

  1. Do you recommend using this Razor 6DOF IMU, what about the Razor 9DOF could it be worth the extra money? I have been trying to make up my mind on what IMU i should use in a similar project.

    Regards
    Magnus

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  2. Hey,

    I had a lot of problems with the RAZOR IMU because it dont like the vibrations of the chassis ;) and I tried different ways to dampen the vibrations but it dont work.

    so I tested die IMU of William.
    then I bought me the same IMU. it flies much better than the RAZOR.


    but i think with change on the Sourccode of William it will work. but I dont know how to do that.

    Greetz
    Sven

    ReplyDelete
  3. Im in the same position with Sven. Im trying to use 6dof razor but im expecting a too much vibrations that i cant make it fly. I have also tryed to reduce the vibrations with springs first and then with foam. The results were slightly better but still ive got too many vibrations. Do you have anything to suggest in order to make things better?
    Thanks

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  4. I built a 3.3v imu from a LY530AL (sparkfun #SEN-09165) for yaw, a LPR510AL (pololu #1266) for pitch and roll, and a MMA7361L (pololu #1246) for accels. I used the 3.3 v supply on the 1266 breakout board to power the other sensors and provide 3.3v reference back to the triguide on the unused 8th pin on the imu header. I haven't had any problems with vibration on my tricopter.
    However right now I am stuck because I want to build a quad but don't have a compiler to change the code for external reference like William did for the tri.

    ReplyDelete