Toilet Bowl Effect

I need some advice on where to start twaeking the PID's to get rid of the toilet bowl effect I'm experiencing


Arduflyer 2.5, flies lovely and smooth just how I like it, spider style quadcopter frame 3.01 firmware

In both LOITER and RTH In a mild wind (approx 7mph) the quad starts getting into the toilet bowl and continues to get worse if left, leave it too long and it gets really wild in RTH


Anyone know what PID's to change to start with ?


Thanks in advance

You need to be a member of diydrones to add comments!

Join diydrones

Email me when people reply –


  • I have a question:

    When I fly with my quad on regions of positive inclination (east), the rotor works great. However when I fly on regions of negative inclinations (west), the rotor starts getting into the toilet bowl.

    This problem could be appeared because I had not adjusted the magnetic declination in the new place?

    Thank you!


  • 1. I must agree with the fact that far too many people are blinded and over defensive of 3DR to the point of it being ridiculous

    2. Version of softwere you can find if you connect to mission planer Terminal window and make USB(not telemetry) connection

    3. if you make your legs from something thinner(carbon fibre,aluminium) surface will be less and you will fly even better in the wind

  • One plast post here for those who've been having the same toilet bowl effect issue

    I re-wired the power cables going to the ESC's to reduce the compassmot, finally getting it down to 7%, that seemed to make little difference but it really ought to be done anyway, interference is never a good thing

    Next was to follow some advice via PM by a very nice guy...

    Advance parameters:

    Enable auto declination

    Enable Auto offset

    These are only temporary !

    Fly the multi in 2 x figure 8's, land, plug it into the PC/laptop and disable auto declination and auto offset

    That's basically it, since doing that the loiter and RTL is rock solid in very gusty conditions with the wind going from 8mph to 23mph in split seconds

    The steps above worked for me, they may not for you, make damned sure to test in a safe place and be ready to switch back to manual control fast


  • Moderator

    Guys - enough is enough.  There has been enough information thrown around here that should help the OP.  All this schoolgirl bickering is just useless. 

    Terry, I ask that you please close out the post if you have found a potential solution to your problem.  If you haven't, please close out the post and add me as a friend.  We will identify the problem and get a solution.

    This post will become heavily moderated in order to remove any useless comments, but please don't waste our time.


  • @Terry: I have never read anything from a more argumentative person in my entire life. You must have the last word no matter what...sometimes knowing when to keep quiet is a good thing.

    You have been told how to correct the problem with you quad several times but rather than spend $3 on an external magnetometer you endlessly complain about a 3DR product which you don't even own and software which is developed by volunteers and provided to you for free.

    You state "So they launched the 2.5 and rather than give them my hard earned I thought I'd place it elsewhere, they'd already had their shot at my money" in relation to your purchase of an APM 2.5 clone, and yet it is evident to me through you lack of willingness to spend $3 on a unit which will clearly resolve the issues you are having that it was purely the RcTimer being a cheaper product that lead you to it's purchase. You then come onto the 3DR forums complaining your clone board doesn't work and whinging at the people that try to help?? I believe you are extremely lucky anyone is willing to help you at all as I have seen a number of times on these forums "we do not support clone boards".

    You then also complain that the APM 2.5 and mission planner have no warnings of basically not being plug in and play. As a six year old would say, well derh!! You even said yourself you own a APM 2.0, so owning one and having gone through setting it up etc. you would be aware that the product is not plug in and play. So why would you then go and buy an APM 2.5 (clone) and then complain it has no warnings, it requires time, patience, research, and other components to set it up and that it wasn't going to work out of the box? I find it laughable that anyone would actually try to argue the point that they purchased a printed circuit board, which the APM basically is, and expected to install it into something without having done some research on it first, and in having done that research would not have realized it is not simply a case of plug A into B, C into D and it's ready to go. Hopefully one day down the road as the technology improves that may be the case, a unit you simply connect and it will automatically learn every aspect of your machine and what it needs to get it flying perfectly, but it's not there yet.
    Honestly, it comes down to common sense, I am yet to work out if you're lacking in it or whether you, like it has been stated, just continue to troll.

    My suggestions, please buy the $3 compass (the time you've spent complaining on here is worth a lot more to you and the others trying to help than the $3, I'll even give you the $3 to have you stop whinging), stop playing so naive in regards to you thinking it would work out of the box as it's getting old, stop complaining about a 3DR product which you don't even own, and yes read the manual.

  • I think the OP had a legit question, especially since he didn't realize the "toilet bowl" was related to compass calibration.  Yes, this topic has been discussed many times in the forums, but I don't think all the mudslinging is necessary.  A simple link to the solution helps everyone so much more than insults.  Play nice, we're all in this together.

  • Because of the lack of effective structure and/or effective moderation of these forums, this thread has now climbed to the No.1 position on the "Top Content" list.

    Here is what can be learned from the seven pages of posts in this thread:

    1. RTFM

    2. Do not upgrade software without first determining that hardware is adequate to handle it.

    That is all. The rest is a lesson in how to successfully troll a forum and everything else written therein is a total waste of the writers' and readers' time. Which is what feeds the troll. 

  • Just an update

    Trying something out to tune the compass but need to deal with another minor issue first

    Now it's got very windy here it's highlighted the fact that I have no cotton wool or gauze taped over my baro

    Stick it in loiter and it drops like a brick doh !

    Job done, food to sort out then out to test again


    Oh and Cody, I have a laptop so no need for "smart" phones ;)

  • The Calibrate Compass instructions worked perfectly on my APM 2.0 using a "mag field vs throttle" calibration with 32% interference.  I've found that Randy's new method of finding the true direction of the magnetic field works much better than the "compass dance".  Use your smartphone/tablet with a sensor app to find the magnetic field direction.  When the X and Y axes read 0, the magnetic field is perpendicular to your screen... unless your axes are labeled differently then mine :-P

  • Damn

    Just been out to test the results of lower compassmot and it's far worse than it was before

    Now even in very mild wind in loiter it gives me a dramatic TBE, before this loiter was OK, it was just RTH when it went into wild TBE but only in winds higher than about 8-10mph

    I did set channel 6 to adjust declination and set the min to -10.0000 and max to 10.0000

    Though turning the knob did make a difference, it appeared to be far too dramatic a change, seemingly causing the TBE to go from clockwise to anti-clockwise with no setting inbetween that made it stable

    I will try again later after having run through the compass calibration again and turned off the ch6 option so I can just test straight how it is right now

    Right now I have auto turned off as recommended

This reply was deleted.


DIY Robocars via Twitter
May 15
DIY Robocars via Twitter
May 14
DIY Robocars via Twitter
May 13
DIY Robocars via Twitter
RT @f1tenth: Say hi to our newest #F1TENTH creation for @ieee_ras_icra next week in Philly. It’s going to be huge! 😎 🔥 @AutowareFdn @PennEn…
May 13
DIY Robocars via Twitter
May 11
DIY Robocars via Twitter
May 8
DIY Robocars via Twitter
RT @SmallpixelCar: Noticed my car zigzagged in last run. It turned out to be the grass stuck in the wheel and made the odometry less accura…
May 8
DIY Robocars via Twitter
RT @SmallpixelCar: Test my car. RTK GPS worked great. Thanks @emlid for their support.
May 8
DIY Drones via Twitter
RT @chr1sa: @kane That's @diydrones circa 2009. Still have a box of those Canon cameras that we used to strap into planes, just like this.…
May 3
DIY Robocars via Twitter
RT @chr1sa: Our next @diyrobocars race is going to be outside at a real RC racetrack in Fremont on May 28. Fully autonomous racing, head-to…
Apr 30
DIY Robocars via Twitter
RT @f1tenth: Our Spring 2022 F1TENTH course @PennEngineers is coming to an end with a head-to-head race as a big finale. So proud of our st…
Apr 26
DIY Robocars via Twitter
RT @DanielChiaJH: I wrote a thing! Throughout the development of my @diyrobocars car I've been using @foxglovedev Studio to visualize and d…
Apr 23
DIY Robocars via Twitter
RT @SmallpixelCar: My new car for high speed. Low body, everything ( @NVIDIAEmbedded Jetson Xavier NX, @emlid RTK GPS, IMC) under the deck…
Apr 23
DIY Robocars via Twitter
Apr 21
DIY Robocars via Twitter
RT @f1tenth: F1TENTH Race training setup @PennEngineers for our upcoming ICRA2022 @ieee_ras_icra competition. @OpenRoboticsOrg @IndyAChalle…
Apr 21
DIY Robocars via Twitter
RT @fatcatFABLAB: Proud to be hosting a restarted DIY Robocars NYC Meetup April 26. Come by if you want to talk about and race self-driving…
Apr 17