This project was started in November , 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). It would be cool to add more features to this project but I am pretty busy with my PhD research. But maybe one day I could combine my scientific interests with my hobby projects...
-- William

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

Tuesday, 20 April 2010

The mini is airborne!

The Shrediquette DLXm micro-tricopter flies better than I ever expected. New control loops make it very stable in fast flights, during aerobatics, when there is wind or when it is flying in it's own downwash/ the ground effect.

Watch the DLMx presentation in HD:
Shrediquette DLXm - Self Stabilizing & Aerobatic Micro-Tricopter. The Movie.



Thanks to Stefan for milling the frame (in carbon fiber, hehe) and to Eric for borrowing the ESCs!

Specs Shrediquette DLXm
Motor shaft distance: 132 mm 
Max. dimension: 259 mm
Weight: 230 g
Props: 5x3 3-blade GWS
Motors: Roxxy 2216-25
ESCs: Turnigy Plush 6A with I²C->PWM converters
Battery: 3S, 800 mAh
Max thrust per motor: 237 g
Thrust to weight ratio: 3.1:1
Total current during hover: 4 A
Endurance: 11 mins

The control loop now processes angular acceleration in acro and hover mode: I finally managed to calculate "up to date" angular acceleration with only little noise. As a result, the gain of the gyroscopes could be increased by 100% which results in a much better stabilization. The new firmware still has to be tested with a standard size Shrediquette, but I am very optimistic.

-> Update: Some test have already been done,I am not yet satisfied with the results of the new firmware on the standard size copter, but I keep on testing...

Friday, 2 April 2010

Shrediquette DLXm

Here are some pictures of my Shrediquette DLXm. Unfortunately I am still waiting for the ESCs... Slightly annoying.

EDIT:The ESCs arrived (thanks to Eric!) and first flights were very successfully completed. The control loop had to be modified to account for higher demands of this micro tricopter during aerobatics and fast flights. Because larger Shrediquettes will also benefit from this modification, I will soon release a new firmware and a modified GUI. I will now start to collect some video footage and make a new movie.