Hello everyone, I've just finished a geprc phantom build on 3 to 4s... works fine on 3s but when i connect 4s and give bit of throttle it shoots into the air with no control over the throttle...i have to disarm it to bring it back down... I'm a newbie to building drones, Any help would be appreciated.. on 3s motors seemed pretty warm after 2 min los... the sort time they was on 4s they felt really hot

You might need some PID tuning. Which I am not the best at. Here is some good things to try if your motor is too hot. If you add some filtering and reduce D-term in PID. Soft mount and capacitor are other things you want and should have.

https://oscarliang.com/mini-quad-motors-overheat/

(08-Jun-2021, 07:57 PM)voodoo614 Wrote: You might need some PID tuning. Which I am not the best at. Here is some good things to try if your motor is too hot. If you add some filtering and reduce D-term in PID. Soft mount and capacitor are other things you want and should have.

https://oscarliang.com/mini-quad-motors-overheat/

Thank you for reply... would pid tuning make the motors spin with bit of throttle and not stop if i lower the throttle? I have stack soft mounted and a capacitor aswell... I'm gonna update firmware on flight controller and add rpm filtering with bi directional dhsot and see if that changes anything...

A badly PID tune can cause a quad to go out of control.

what parts do you use? what is the weight? what batteries?

as a short try, you can decrease all pid values by a half at least a third and give it a short try, it shouldnt get a runaway from pid than, as 3s works on that values. if you i would still get runaway/controll loss i would look for a source somewhere else; esc firmware, hardware- mountings, stiffness of the frame...

(08-Jun-2021, 10:39 PM)hugnosed_bat Wrote: what parts do you use? what is the weight? what batteries?

as a short try, you can decrease all pid values by a half at least a third and give it a short try, it shouldnt get a runaway from pid than, as 3s works on that values. if you i would still get runaway/controll loss i would look for a source somewhere else; esc firmware, hardware- mountings, stiffness of the frame...

I'm using a geprc phantom frame, flywoo goku f4 stack with 20a esc,flywoo vtx, flywoo 1204 5150kv for 3-4s,runcam nano 2,radiomaster r81 receiver, dry weight of 62grams using 450mah 3s and 4sgnb lipos, I'm gonna play around with the pids and try what you said, pids is one of the things i don't understand really properly so i guess now is a good time to start learning about them properly.... I've updated firmware from 4.2.0 to latest 4.2.9, just need to do bi directional dshot and rpm filtering then play about with the pids then ill give it a go... thank you

i would check lower pids first, i dont see a reason why rpmfilter could solve that issue. it might be a nice feature, but not to solve that issue.
did you use default filtersettings?

https://intofpv.com/t-rpm-filtering-setup
take care for the magnet number and about cpu load by "tasks", not to get in an additional issue with rrpmfilter.

(08-Jun-2021, 11:42 PM)hugnosed_bat Wrote: i would check lower pids first, i dont see a reason why rpmfilter could solve that issue. it might be a nice feature, but not to solve that issue.
did you use default filtersettings?

https://intofpv.com/t-rpm-filtering-setup
take care for the magnet number and about cpu load by "tasks", not to get in an additional issue with rrpmfilter.

ok I'll leave that for now and just lower all the pids... ...i left all the pids and filters how they were on default settings i just connected it to my transmitter

( i suggest to lower all values for troubleshooting to sort out high pid values as the source. if they are the source, it would be just the beginning of tuning process as solution.
my personal choice would be emuflight for your power micro and tuning issues)

(09-Jun-2021, 12:21 AM)hugnosed_bat Wrote: ( i suggest to lower all values for troubleshooting to sort out high pid values as the source. if they are the source, it would be just the beginning of tuning process as solution.
my personal choice would be emuflight for your power micro and tuning issues)

What is emuflight? Similar to betaflight?i flashed the latest firmware 4.2.9 and now it's working on 4s... motors are still a bit warm... I've not had proper chance to have a long flight but atleast its working now, I'm gonna lower the pids today like you said.. should i lower every single pid by one third to start with? Thanks

I would suggest to stay away from emuflight for now. Its good, but most tunig guides and infos are tailored to Betaflight and for Beginners its easier to follow. When you are comfortable with the basics, try it out and decide for yourself. All the principles for Betaflight can be applied to Emuflight

If Motors are only warm to the touch, I would keep it like that

yess i would lower all values (excluding feedforward) but just as a try about the issue. its about your particular issue and not an suggestion to use it as start values for tuning, but you can start from there if the issaue is gone on lower values.

emuflight is a fork of betaflight 3.5, its mainly the same with other features.

betaflight is such a mess today, as emuflight is more basic than a modern 4.2 - i dont see why a beginner would struggle more. the reason of simplicity is why i suggest and use it.

there are endless vids for betaflight and all kind of levels or deepness, overall beginers are hopeless to interpretate it. one thing we see: beginner the request for rpmfiltering, while it can be nice for improving the performance, beginners believe its the main thing for performance from the reviews - but it comes faraway after other settings. while betaflight is to focused on 5inch performance, emuflight has a more wide range where the defaults match: the settings befor any peakperformance improvement.