I have been trying to get a better grasp of notch filters and how to set them up but have been struggling to understand the numbers and log I have. This is a small 5” quad based on the QAV250 frame. it is running the holybro pixhawk mini 4 with a F9P dronecan GPS and some led lights externally. I have been working through the initial tune setup and believe I have all the setup right for what I am trying to accomplish. I have made it to 3. Evaluation of the initial stable tuning and see no issues with the initial tune. I have moved onto setting up the log for the filter review tool. I have performed a small flight in my large shop bay (its snowing/raining where I live) and have brought it into the filter review tool. I just don’t know if its a good log or where to start to look on what the correct numbers are. Hoping someone can help me understand what numbers need to be looked at or what numbers I need to use and why. I have watched Iampete filter review tool video and read through the Managing Gyro Noise with the Dynamic Harmonic Notch Filters. Below is a short log from the flight and a current config. Any help is appreciated.
You are misconfigured to collect Notch filter data with that Flight Controller. Set these:
INS_RAW_LOG_OPT,0
INS_LOG_BAT_MASK,1
INS_LOG_BAT_OPT,4
I would also suggest you lower the Rate PID’s before advancing. And set the Motor Ranges as they are at default.
Then make another hover flight.
What ESC’s do you have? There are errors. And relative to how you are logging the main loop rate is always lower than configured (unstable) and the processor load is high.
You are focusing on the Notch, but forgetting other configurations that need to be done before the flight that collects the data for the notch filter. This is a common mistake.
for now, @dkemxr already pointed you in the right direction, but for future builds use AMC software to avoid this and other similar issues.
It sure has become one. Making suggestions about Notch Filter configuration can be rather pointless if prior configuration and tuning steps are not completed first.
Can you point to where in the documentation it shows these. I have looked at the filter review setup and the batch logging in the copter docs and these don’t match what the docs say. I just want to make sure I am reading thing in the right order or even the right setup. Understand this is a F7 and not H7 which limits capabilities.
Reading about mot spin min it says for hobby use you can use default. so should I not use default and set both of them?
“MOT_SPIN_MIN: use the motor test feature and motor test data, if available, to set the lower range of linear thrust. The default value is usually adequate for hobby uses.”
The stock ones that came with the older Holybro QAV250 they were blhelis then upgraded to blue jay.
Not sure what you mean here, I haven’t done anything with the loop rate and could it be possible the logging I choose for this fc was overloading the processor? I bought these off a fella that could never get them to fly and thought I had did a clean parameter update but it may be these still have a lot of params from the individual I bought them from. I went from copter to rover then back to copter so I figured they were wiped out.
What is the best way to wipe params I was always under the impression going to different vehicle would do so?
In the wiki documentation it is probably scattered over several pages. But on the AMC software these parameters get automatically correctly set depending on you processor and propeller size in the 14_logging.param configuration step.
On step 15_motor_test.param you should set MOT_SPIN_ARM to the minimum value at which the motors reliably spin. And set MOT_SPIN_MIN 0.03 above that.
I appreciate the push toward using your software but I used it early on and found it to not be very helpful for the way I learn. I don’t learn well when some black box per say is telling me what to do. I want to see where its written read it and be able to go back to it when needed. I like to read how things are done but in its current state I cannot follow how to setup anything based on the wiki because there are as you say so many pages you have to look at for information. I see the AMC tags sections in the wiki but even then does it explain it all on that page or section or must you also go to multiple other pages as you mentioned.
Yes, and that is why you should use it. It is not a black box, it is a guide, that navigates you thru the maze. The explanations are there and you are supposed to read them before doing any step.
There are so many motor range pages. It get so hard to follow using the wiki. one page says this about motor range, “Configure Motor Range (optional)” Yet I am told I did not follow the steps right but there are so many different pages where one step says one thing and then the other pages says a completely different thing.
I will look at that link and see if it matches up to the 3 other pages where motor range is discussed. There is a lot of contradictory statements being made and as you pointed out that is bad advice. Can I ask why no one has updated the wiki if this is improper advice and the wiki is the ultimate source? Thank you for pointing out the PM graphs processor load. I did not know what to graph to expose these items.
@amilcarlucas
Again I appreciate the effort trying to push folks to your software but as mentioned earlier it is not conducive to how I learn. My original foray into it in its early days was a disaster. Given that can we please focus this not on AMC and more toward the topic at hand? I do believe there is a AMC thread where you can discuss what it can and cannot do.
The only thing I see that needs changing is to remove “(Optional)” from the Mandatory Hardware Configuration page link description. So I put in a PR to do just that.
Mot-spin-min/arm were set excessively high for this quad at least. Defaults were not close all my motors spin easily at 1% so I set mot_spin_arm to .03 and mot_spin_min to .06.
I completely wiped this FC (to rover back to copter and did not apply any old param files) and started from scratch again. I have no idea what is causing those errors on the ESC at first I thought maybe it was the EDT setting and they don’t have extended dshot telem but I turned that off and back to just blhelis-bluejay but those errors persist. I have 4 others that are identical except GPS I can see if those also have errors (the guy I bought them from was trying to do a swarm of 5 to play with).
I did lower ATC_RAT_PIT_P, ATC_RAT_PIT_I, ATC_RAT_PIT_D, ATC_RAT_RLL_P, ATC_RAT_RLL_I, ATC_RAT_RLL_D by 50% just so I could graph the RCOU in the log (this is what would show motor pulses correct?) to see what it looked like and they look cleaner but still a bit busy.
here is a log of a short flight just checking some things over and checking the initial compass calibration haven’t done a magfit or any of that yet.
You need to deal with the mechanical vibrations before you go further. Something is loose or your props are bad.
You can add a filter, but that’s a band-aid on the mechanical vibrations. Consider these settings temporary until you have the mechanical issues addressed.
I would guess its from the massive GPS and GPS mast wiggling about. I haven’t found anything loose on it anywhere and all the wires have plenty of extra where they don’t seem to be tugging on anything. I could clean up the extra wire in the back but other than the mast I cannot find anything that would be causing vibes. I do have a smaller (also less weight) RTK GPS but I think a lot of the vibes are from this mast possibly. Will keep looking!
Understand those filter settings would be a band-aid but other than the 220 where did you come up with the BW and ATT numbers and you choose INS_HNTCH_OPTS 2 (multi-source) so it track each motor correct?
Yeah, that monster of a GPS receiver and the loose wire wrapped around the mast are probably a big part of the problem. Those masts are also notoriously issues. You need to find a different way to mount that GPS.
so are you telling me that even a F7 is incapable of running ardu in any capacity that allows for anything of usefulness? How can a gps (can based), crsf rc and a telemetry radio be overloading that much? what does normal look like, the scales to me are french what is a good PM NLon and PM Lr number. I just see 2 lines and a scale that makes no sense.Vibes aside would cutting a bunch of non needed stuff out in custom build be worthwhile such as all the rc protocols I won’t use airspeed sensors that would not be used on a quad copter, etc….
non-can based GPS
custom build with a bunch of stuff cut out thats not needed for what this quadcopter is about listed below. It looks like PM.LR (Performance Monitoring - Loop Rate) is remaining fairly consistent at 400hz ish so that shows fairly stable. PM.NLon (Performance Monitoring - Number of Long Loops) is not zero but didn’t steadily climb. Is this showing a somewhat stable loop, what is a bad number for PM.Nlon?
I have a excessive amount of other flight controllers plenty of H7. I just hate having these sit around for waste if I can make them work. They would be handy to teach people flight maneuvers and basics of flight. If they crash then shoot its not a big loss I got 5 of these whole QAV250 for 200. Guess you get what you pay for.
Here is a Kakute F7 Mini with the default loop rate of 400Hz. Typical configuration with ESC Telemetry notch running as multi-source. Stable Loop rate and no Long Loops to speak of.
Here is an H7 with an 800Hz loop rate with a similar configuration but the Notch running on all IMU’s. Processor load shown here as ~50% It’s burdened but running fine. At 400Hz of course it would be dead stable.
