New to Log Analysis - What am I looking at?

#1

Hey Everyone,

New to the forum, and learning to look over my logs. I have a 400 that I built on top of the Pixfalcon board over the last year and I have been having trouble tracking down the issues based on trial and error.

Finally learning to use the logs and I’m starting to recognize what I’m looking at. I have attached the log of my most recent (relatively) successful flight and would like someone with a better eye to point out some of the things that stand out to them.

From what I have gathered, my PID’s need adjusting. It seems like the controller is doing well responding to larger displacements, but it is not keeping up with the lesser vibrations. I am unsure also if overall vibration is excessive leading to additional instability? Any comment on that would be swell.

I have tried adjusting PID’s before, but this is an arduous process that I feel like I’ve been going into blind. Is there any example of information in my logs that you can point to that might help narrow down the proper adjustments?

I have also noticed that the magnetic fields seem pretty high, and am working on relocating my external GPS and adding some shielding between power distribution and the GPS. I am hoping this will take care of the “toilet bowling” issue that shows up in position hold and loiter modes, as well as the periodic mag and GPS failures.

I realize this is a lot of basic information covered in the wiki, however I have spent months pouring over that and finding myself with a lot of ideas but no real direction as to narrowing down the underlying issues with this build.

Thanks!

  • John

https://logs.px4.io/plot_app?log=e7549450-9ba0-4ea8-8d79-acfa533d66d3

#2

Also looking at a redesign of the interior layout of my electronics. I was going for a compact design on this frame and so i designed from the ground up around CNC aluminum and 3D printed PLA.

Based on my research, I am thinking that the GPS is way too close to my power distibution (bottom of stack) as well as the servos for my gimbal. I ordered some mumetal for shielding the card, but was wondering about by flight controller. Should I also shield that from my power distribution board on the bottom of the stack?

ESCs are not shown but are mounted on each of the arms externally. Would moving these underneath the arms help at all with magnetic interference? I was thinking the 1/8 inch aluminum might help with the overall magnetic interference being seen in my logs from my previous post.

Anyone who is willing to throw some suggestions my way, I greatly appreciate it!

Thanks,

  • John

For reference, the bolts are m3.