Shrediquette - the award-winning multirotors by William Thielicke

I added a GPS module, a compass and a pressure sensor to my tricopter to enable automatic position hold. GPS is implemented using a PD control loop, compass is P only, and height is PID. And... it works! Still not optimal, but in principle it is already ok. There are some things that have to be optimized of course, e.g. a one-axis compass will probably not work for waypoint navigation and position hold when there is wind. And my code is still far from being optimal. At the moment, I have to make my copter hover at the position + height that I want. Then, I flip a switch (connected to channel 6) - current position, heading and height is stored and used as setpoint for position hold. I think I will have to switch to a 3-axes compass in combination with an additional 3-axes accelerometer. That will enable tilt compensation for the compass, as well as improving the D-term for height stabilization. The tests that you see in the video where done with no wind at all. The tricopter stayed mo...

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)...

Changes: Gyro offset measurement changed. Right after the startup, the copter tries to measure the gyro offset. If the copter is moved during this period, it won't continue with the start-up. Instead, it will flash the LED in the middle until the copter is placed on the ground. Only then it will initialize . Servo control improved: The servo pulse generation is now synchronized to reading out the receiver. Additionally, it is not possible anymore that an interrupt makes the servo jitter (thx to Lutz Meyer). All servos should work much better now.

Some days ago, I added two FPV videos to the video-section : There are also some more details on the FPV setup that I use in the FPV section. Additionally, there is a new section showing some Shrediquette user builds . Please keep on sending me details about your own build. Soon (next days) I will release a firmware update, that seems to reduce servo jitter, especially when using fast digital servos. Lutz Meyer tweaked some lines of the source code (thanks! :-D ). Lastly, for all people from northern germany, I would like to point your attention to a quadrocopter meeting that will take place on Aug. 21. in Bremen .

Time for some statistics...: Although the word "Shrediquette" seems to cause some confusion, still some people found their way to this blog. Here is a bunch of google search word logs: Thanks to all the visitors, I made a quick video for all of you (don't try this at home...):

This year, a friend of mine and I both decided to go to the IMAV 2010 with our "flight devices" ( Tumba with his autonomous Lerche 400 & 500 planes , and me with my Shrediquette DLXm + my brand new FPV goggles ).  Participants came from many countries to attend the conference and to compete in the four competitions . I participated in two of them:  indoor flight dynamics and outdoor flight dynamics (as the GPS add-on for my tricopter isn't yet finished). The competitions were great fun, I especially enjoyed the outdoor competition where I used a FPV camera for the second time (I had a total of 16 minutes of experience with FPV). It is so cool to fly around in 3D space! I will definitively spent "some" time using these cool video goggles! This is my setup for outdoor flight dynamics: The Shrediquette DLXm was the smallest MAV in the contest (this yielded some extra points). The results make me especially happy :-D : 1st place outdoor flight dyn...

Paul Escalier from TomsGuide.com just finished his article on my tricopter. It has become a nice story I think :-) Make Your Own Gadget: From Idea To Reality Table of contents A Time to Make Something Awesome A Little Bit of Background The Birth of an Idea Taking the Plunge: Buying Some Parts Building the First Prototype Overhaul: Taking the Prototype to a New Level A Few Polishing Touches and a Mini Conversion Future Developments and More Information Have a look at the article here: http://www.tomsguide.com/us/tricopter-diy-gadget,review-1552.html