Hi Guys,
Lust wondering if I could get some help tuning a 30" custom frame drone.
The tuning was pretty good, went through manual tuning in the arducopter process.
Haven’t setup the dynamic notch filter, I will try that. Also I could try the auto tune again, not sure if that will hurt?
One thing I tried was changing the yaw settings (sluggish yaw) but I think that made things worse. Being in stabilize mode I think the drone will drift while trying to yaw anyway, but I might try bumping max yaw acceleration up too…?
Regards,
Josh
There are excelent step by step instructions on the wiki. Makes little sense to repeat them here.
There are templates for similar sized vehicles on the ArduPilot methodic configurator software. Those are even easier to use.
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@Leonardthall
Hi again Leonard, let me know if you can help. Much appreciated!
If you need hardware done let me know, I have a CNC now so making my own frames.
Josh
Sluggish yaw is a fact of life with most large multirotors. Your inertia is going up and the propellers are becoming more efficient. More efficent propellers have less drag and therfore less holding power for yaw. I say holding power because the fast response for yaw control is actually the change of propeller rpm and propeller inertia and that is generally good for large aircraft. Unfortunatly the fast response time is of the order of 0.25 seconds so it has limited ability to increase overall yaw control.
So what can you do.
- Tune up yaw as tight as possible. Autotune should do this well. Don’t bother with D term.
- Make sure that Yaw outputs arn’t so large that they are messing with Roll and Pitch. Reduce them if needed. (I do this often on large aircraft)
- Use low Yaw acceleration. Autotune will give you a maximum value but you may benifit from reducing it further.
- Use a maximum rate that is no larger than your acceleration value so the yaw will take no longer than 1 second to stop from max rate.
- Adjust your flying style to suit the limitations of your aircraft.
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Thank you Leonard it’s much appreciated!! Yes I noticed when you yaw sometimes I was pitching the same direction. Especially noticeable with wind, so much that I lost a fair bit of altitude.
The ArduPilot wiki is great, at some stage I will go back through all the parameters and try to understand what they all mean!!
Control is very interesting, I like to pretend I can grasp the yaw and inertia relationship but I am greatly thankful of Autotune 
For large multirotor platforms (and VTOL platforms) adding 3-5 degrees of tilt to the motors can greatly improve yaw control while pretty much maintaining the same level of efficiency.
Some discussion here: Circumferential Motor Tilt for Increased Yaw Authority - #6 by lordvon
Paper here: https://hiperlab.berkeley.edu/wp-content/uploads/2018/05/2018_TiltingMulticopterRotors.pdf