Non Quatos Build Problem

[pilotnbr1]

Ok so I have just discovered that a dimu not oriented correctly in regards to "flip" will make it appear that you have significant gyro drift. I would have thought that if flip was wrong it would show the M4 upside down or however it thought it was oriented. Guess I'm thinking of it all more like a real airplane and attitude indicator always aligning to horizon, whereas this needs to be calibrated to horizon.

Larry I loaded your params and am going to finally try to fly this thing again! Thanks everyone and sorry to cry wolf and make you listen to my ramblings- I hope this all can be helpful to someone else!

[Max]

Hehe, no problem... we both forgot to mention to set the IMU_FLIP and IMU_ROT (rotation) correctly for your build! Glad you figured it out... it's better that way anyway!

Crazy flipping on spoolup is almost always either wrong prop direction or a mixup with the flip/rot and motor mix. Even if you can swear everything is set up correctly... don't ask me how I know!

-Max

[LPR]

Luke

Sometimes a picture is worth a thousand parameter changes.
I have the M4 board with the GPS receiver up and the blue LED on the left when viewed from the rear of the quad

Larry

[pilotnbr1]

Thanks guys! Got it flying! I think I had sime orientation confusion after loading so many different parameters I lost track of what was what.

My last big mistake was copying the propellor layout from my old hubsan and carbon-h. Every prop was turning the wrong way or motors not in the correct position, however you want to look at it . Interestingly enough is that it would fly for a little bit and was spinning the whole time. Lol...

Now just to fine tune and learn all this gps/autopilot/mission stuff.

Thanks for all the help! And very cool frame Larry! I like the inverted motors and efficiency. Makes me want to buy a 3d printer- but my wife would kill me.

Heres my little hack job.... With a 750 lipo it weighs just over 60g. I need some lighter motor mounts..

[LPR]

Luke

you only need a very small piece of foam not much bigger than the barometer. Make sure not to use the foam that comes with electronic components. That foam is treated to control static and it will cause a problem with altitude control.

Larry

[pilotnbr1]

Thanks Larry, good to know! I swapped out the foam.

I have to say that the M4 is amazingly stable! It is a little bit of a different flying experience as it also does not overshoot as much when making abrupt direction changes. It is also amazingly adaptable to moving weight around the frame and some of my design imperfections.
I damaged one of the motors in the picture today (the motor core began to rub and create alot of friction, I tried the casing compression trick but no luck) so I swapped motor shells with a dead dark edition. My work wasn't perfect and the rebuilt motor still had some internal friction which I think would have been unflyable with the Hubsan fc. However with the M4 it flyies just fine!

Now to solve my gps lock issues with my dipole and patch... I see theres another thread on that.

[LPR]

Luke

Using a small ceramic GPS antenna like you have you should try a ground plain that around three time as large as the antenna. The ground plain can be made out of tinfoil.

Their is info in the AQ wiki on how to build a very light weight dipole antenna. I find they work quite well, surprisingly.

Larry

[pilotnbr1]

I built a dipole initially but was not having much luck even after leaving it outside for over an hour at one point (Atlanta Georgia). Part of it is my fault as I have a very private backyard with lots of trees and obstructions.

I revisited the dipole after even less luck with the patch ( I might try the ground plane down the road). I decided to clean up the dipole and try better locations. So now I am getting a solid blue light after about 20 seconds . However my newest problem is the quad behaving eratically as the 3d lock is lost and regained particularily in ap/hold mode. It seems like it is almost chasing an exact fix. I am going to have to research it- my first idea is that I need to loosen some parameters regarding nav...

Luke

[LPR]

Luke

No, the only way to have a good GPS controlled flight is to have good GPS reception.

It's just warmed up enough in Minnesota to be outside flying and I have the Nylon quad flying great with the dipole antenna most of the time.
If you try to fly right after you first get a GPS lock you often get erratic control. I don't know how you could change any parameter and fix the problem with GPS reception.

Give the GPS more time after you see the blue LED and try again is my advice. Changing the length of the GPS antenna a small amount can make a difference. The wire you use and the cable you use all make a difference. I've been quite lucky just following the wiki instructions on how to build a dipole antenna.

On my Nylon quad I have a lot of trouble using bluetooth module. The bluetooth reduces the quality of the GPS signal and makes the mags not work well. I'm not using the bluetooth very often on the Nylon quad.

On my ladybird quad I have not had a problem with the bluetooth.

Larry

[pilotnbr1]

Thanks Larry! Good to know. I have been having good luck with the dipole now after I cleaned it up and made it much more straight.I also adjusted the pid tilt rate d from 5000 to 6000. It seemed to smooth out some of the abrupt direction changes.