Comment by space_nut on June 25, 2010 at 12:11am

Follow the trail and you will find that he is programming an Arduino Pro Mini but using BASCOM-AVR. It seems a little clunky to get the programming environment up and running but the performance of the code, especially for analogRead and other commands seems more efficient than Arduino. See this comparison

I'm not advocating that we adopt BASCOM but the project is very nicely documented. Good source of ideas methinks.

Comment by Peter Seddon on June 25, 2010 at 1:48am

William Thielicke is the designer of Shrediquette and has done a great job with both a 'normal' sized tricopter and the very small DLXm. I don't know why you call the programming environment clunky - the hex code that he provides can be loaded using the excellent GUI that he has written using the bootloader built into the arduino. If you are a Bascom user then there is no reason why you cannot use normal bascom programming via the SPI port.

The tricopter is slightly different to the quad, hex and octo -copters as it requires one motor to be mounted so that the angle of the prop relative to the two fixed props can be varied by a servo to give yaw control. This adds a bit of mechanical complication but works very well.

I am not aware that William has published a hexacopter design. He is currently working on autonomous control using a GPS and magnetometer for his Tri.

Having built both the MK Quad and Shrediquette I think the Shreddie is more stable.

Peter

Comment by tazdevil on June 25, 2010 at 5:51am

Yes , shrediquette is more stable, I do 400m long fpv flight betwen Tree with the heli, very impressive.

I can't go far away cause of a radio lockout :) but it's possible

Comment by space_nut on June 25, 2010 at 8:45am

Please forgive my comment about the software - I meant to say that the BASCOM-AVR programming environment seems to be more difficult to set up than Arduino. This is only an issue if you want to modifiy his base code like we do with Ardupilot. As you say, the GUI interface is just great for configuration "out of the box".

Also, I did not want to spawn (another) email war over which Micro/Language is the best.


BTW, did you see the acrobatics he does with this thing? Apparently he won some kind of heli "drag race" and a "limbo contest" with this design > future TTT's maybe?

Developer Comment by jasonshort on June 25, 2010 at 1:43pm

The Arduino library abstracts the hardware with a performance hit. If you want to do anything special, try AVRFreaks for code examples. Any code you write that doesn't call Arduino libraries will still compile and run faster, but it will be tied to the chip you're compiling for.

In Ardupilot 2.x, we don't bother with the lower level analog in methods because there is no performance constraint driving it. We do however set the pin registers for the throttle output because they happen in a very time sensitive interrupt loop. Look around, there are many chip specific (ATMEGA 328) optimizations wherever possible.

Comment by Jeshua Lacock on June 26, 2010 at 8:22pm

I actually prefer how the Shrediquette tilts the motors with servos to control direction; the chassis does not have to tilt to turn. With the AeroQuad, the entire chassis tilts which seems undesirable for AP. I hope that tilting the motors will be an option for the ArduCopter, or at least a straight forward hack.

Comment