Omg I needed this so bad. Seems like maybe some of this was hard coded in previous bf releases, and now it's controllable so they disabled by default? I have been having trouble tuning out this exact characteristic so thank you so much for making this Joshua
Hi. Just wanted to say a big thanku for fixin my problem with my no motor spin. U were right saying only pwm works with my esc. Ur a genius. Thanks so much
Mad! Can't wait to give this a go. The copter dipping and yawing on throttle chop has been killing me! I hate the feel of high I gain so I'm going to lower it a lot more and go with higher anti-g. Thanks Joshua!
Thank you for this video! I had this issue happening with my brushed quad yesterday and remembered watching this video last week. A quick change in settings and it took a great deal of the pitch out of the turns, which helped keep it in the air.
Once again I both learned something today and applied it to my quad to make it better. I bought the Kakute f7 v1.5 FC and set anti gravity to 3.0 as recommended in the manual. Everything was perfect so I left it. Then I switched to digital and put a Caddx Vista in the back of my quad. I noticed during my first flight that the camera had a dip in it after punches. I thought for sure this was the 3d printed camera mount being goofy. I don't know enough about tuning to fix it, so I just left it for the time being. Stumbled across this video while watching other Bardwell videos and it explained my issue to a tee. I guess having the vista in the back has made my quad somewhat rear heavy meaning I needed to change some parameters up. Thank you!
Josh, can I humbly submit turning the audio gain down on your intro clip.. its a little on the loud side next your soft spoken voice. In the headphones its like BOOM BOOM suddenly.
I'll take a look at it. The volume for this video doesn't actually conform to my normal standards. I normally compress my voice but I forgot to add the compressor during editing, so it may have been quieter than normal.
Dude thanks man -- I was racking my brain as to why my pitch axis was dipping on throttle cuts. Just enabled it for my next session - we'll see how it goes!
Your idea towards the end of the video of adding a visual, on screen representation (throttle meter) to help tune the threshold is a great one. It would help a lot, the same way the quad model helps me to flesh out my rates in the rateprofile settings tab.
@@JoshuaBardwell Wow! I'm excited to see it. Visual feedback is always a big help in my experience. (PS I mentioned to you guys in a previous video that JB is Earth's Jor-El.....😁)
thanks again for your efforts as i spend more time flying then researching these days so having you through this new stuff out there really helps cheers and keep up the good work
very cool. however you may have made a slight mistake in your description. i'm just looking at it now on my quad and I notice that the default value for Anti-gravity gain = 1.0. which makes sense because once you hit the threshold it will multiply the I term by 1 and therefore it won't change (i.e. anti-gravity is turned off). In your video you say that the default value is 0, and that means it is turned off. i'm thinking that if you make the gain =0 then once you go pass the threshold then it will multiply the I term by 0 and you'll be getting rid of the I term instead of not affecting it. if this is the case you may want to update the video to clarify this because people might start setting the Gain to 0.
Great video once again Joshua. Your channel is definitely one of, if not the most useful of all the quadcopter channels. I don't say that lightly. Your intro line of "your going to learn something today" is very fitting. Sorry for the somewhat off topic question but your the guy to ask. Can two different ("brand") flight controllers with the same gyro, with all the same settings on the same quad have different flight characteristics? I assume no but I really don't know.
+helicrashpro all flight controllers running the same firmware with the same gyro will have very similar flight characteristics. There may be some small differences in their noise sensitivity for example bur the basic flight characteristics are primarily determined by the firmware.
Ive been struggling with this. I thought it was my I gain, but I ran into an issue where raising it too high would cause my pitch oscillations to be more dramatic. Giving this a test now. Can't wait to give it a shot!
I tried this out on my betaflight 3.1.5 airbot F4 , placed default i gain and brought up anti gravity to 2.5, was better than leaving it at 1.0 on stock I gain. Thanks for the tip.
Y A S E ! ! ! Now it's completely demystified and super easy to tune :) I hope Felix and crew add something similar on KISS firmware so all my drones aren't drunk with power in the future. Looking forward to tuning this on my tempest.
I think that the attitude/throttle coupling that you explain at 1:00 is caused because the center of gravity and center of thrust of a quad do not perfectly align which introduces a moment, rotating the quad. Regardless, your videos and explanations are great, love them
Thank you for this i had a v -tail from eachine that would dip so far you would freak and back off the throttle. In short extremely inexperienced pilot lost all authority copter continued to roll tail down now and into the ground ........ end of flying for the day :[ i had no idea what this option was and how or why to use it. LOL i learned something too late today. Thanks again i really appreciate your work for myself and the hobby.
Josh your 1 clever bloke iv learnt loads from your videos an still learning I'm pretty new to quads and just getting into tuning now especially now iv transitioned to acro flying only problem we have in England we don't get many flight days for our big quads so i fly a lot of micro brushed do you have any tips on brushed setups and the beebrain fc for the tiny whoop? ps keep up the good videos mate
Might be worth adding an annotation in this video at 4:30. The defaults are now: anti_gravity_thresh = 350 anti_gravity_gain = 3.000 HOWEVER there is a mode which turns it on so technically the default gain is still 0, definitely worth noting though.
Thanks Josh , as always i really enjoy all of your videos and as always i learn something new everyday ;) This Anti gravity thing i have never thought i could understand it , really simple explanation , everything makes sense :) 10x again
Cant believe I passed over this video. thought anti gravity was not interesting. Turns out it is very interesting. Maybe now i can turn my I term down. I currently have it set to 90 on my chameleon trying to get rid of that punchout sag. Thank you.
In the CLI. If you type in the command Dump you'll see all of the settings. You can scroll up to set anti_gravity_gain. Its set to 1.000 by default. To change it. Instead of typing dump you'll type in set anti_gravity_gain = 2 then press enter then type Save and press enter. To make sure the change took on the CLI command type dump and scroll up to set anti_gravity_gain to see if it now says 2.000. To go back to default settings just type set anti_gravity_gain = 1
Totally makes sense now. Great video. What about with racing quads? If you turn antigravity on and give it full throttle... do your quad get sluggish on a full throttle? Or does it still work well on racing?
Hi Joshua ! Thx for the tiip !! I will defenately do that. I have a quick question tho, how can u see your pids in your screen while flying ? I understand how to make the adjustments in flight but how can you setup the display to be able to see the numbers in the screen ? Thanks again Joshua :)
Joshua maybe your next video can you explain what this feature is on the configuration page of betaflight on the Lower left side. It's about camera angle. What happens if you enter a value here?
It'd be really cool if Betaflight could add an Anti Gravity status indicator on your LED panel. The same way you can have LEDs automatically flash warnings. I like to do initial P and D ballpark tuning line of sight. It'd be perfect to just have my LEDs flash a certain color when the Anti Gravity threshold is met. But also, like you said, an indicator in OSD would be cool too.
Hi +Joshua Bardwell This might be a stupid question, and it might have been asked before, but here i go: will tpa interfere with anti_gravity? i am getting massive tilts on my quad when doing full throttle punch-outs, might even do a weird flip... once i turn the AG off, that behaviour diminishes...
TPA and anti gravity are separate and distinct. TPA attenuates P and D when throttle is high. Anti_gravity accentuates I when throttle moves rapidly in either direction.
Hi Joshua, Damien here. I am having issues where like you said I am deducting from your information I'm getting I gain Wind up(Railing along do a snap roll and it just keeps spinning out-of-control till it hits the ground) I have just freshly built a Tokio SX with a Emaxs Magnum stack & F60 motors I'm running Betaflight 3.2. Stock PIDs, rates are up to give me about 1050°/s, filters I have PT1 turned on and the first filter turned off. I had the antigravity set at 2.5 and it happened then, I lowered it down to 1 and it happened? do you think Wind up is still a possibility with it that low? I'm going to go out today and try it with antigravity turned off entirely but I was wondering if you think there could be something else creating this wind up? Hopefully I hear back from you and thank you for your time!! Amazing videos by the way!! Much Respect!
Hi Joshua, very interesting as always. I'm having roll/throttle coupling issues, had to set roll I to 115 to have it disappear. Will antigravity fix this or does it only boost pitch and yaw I?
Do you have a video where you talk about iterm windup? My quad seems to be having an issues that seems like what you describe windup to be. It only started when I went from a 5040 to a 5051 prop. I don't have antigravity on.
I feel like the problem is that the copter is just trying to keep the angular rate. The delay of the i-term will cause a small absolute angle variation. But since the angular rate is constant after that, it will not try to get back to the old attitute. If the copter would really hold a certain angle set by the angular rate, the pitch movement on throttle changes would be corrected alot better. It would behave like a heading hold gyro for rc helicopters then.
+FPV_BENNY the integral nature of the I term means that it will in fact try to return to the previous position. This is exactly what I term windup is. It's just that the I term's time window of influence is so short that it can't recover from a disturbance that goes on too long.
It will not really try to go back to the exact angle, it tries to keep the desired angular rate. When the quad is hovering, and you would tilt it by hand 45°, it will fight you as long as you rotate it, but when you leave it it will not get back to the previous attitute. When you move it quickly by hand, there will be a small rotation back to the previous angle because of the I term windup, but it will then keep the new angle when the angular rate is 0. When I fly forward and quickly increase throttle, the nose will go slightly upward and stay there. When I rapidly decrease throttle, it will move a bit downwards and stay there. A quicker I term (thanks to anti gravity) will reduce that, but a true heading hold like in a helicopter gyro would make the nose go back to the true angle where it was before the throttle change.
But the integral nature of the I term means that it accumulates previous error and attempts to correct it. This results in it trying to return to the desired angle--conceptually at least. The reason you don't observe the copter returning precisely to the desired angle is that the I term also decays over time, to prevent excess windup, and the time constant of the I term is so short, that the I term decays before the accumulated error can be fully corrected.
Think about it this way, let's say in loop 1 we have an error of -10 degrees per second. In loop 2 we have an error of -20 degrees per second. We now have an accumulated error of -10 + -20 * the looptime degrees per second. If we then cause the copter to move +30 degrees per second for one loop, we will have returned to the previous angle exactly. This is precisely what the I term tries to do, although practical considerations prevent it from working perfectly.
The copter would not try to return to the desired angle, just to the desired angular rate. The PID-loop right now has no idea of the absolute angle of the copter. Same with a regular heli gyro. It only counters the change in angular rate, i.e. by wind. A heading hold gyro really holds the angle of the tail. When you rotate the tail by 90° and hold it there for a few seconds, it would still go back to the previous angle as soon as you let it go. A copter or a regular heli gyro would just see the new angle after the 90° rotation as 0 angular rate and stay there.
I have one betaflight quad, and one kiss quad. this is great news for my betaflight quad - do you think the kiss folks will be adopting this same new feature? i'm having *exactly this problem* on my kiss quad.
I'm running 3.2 with anti gravity switched on, tried adjusting the gain but the coper tumbles worse after I punch out at times it's pitching forward up to 90 degrees
Great video Joshua! Have you noticed any negative sides of going a bit high on A_G_G ? like 10-15? I just checked, and stock settings on 3.1.0 was 4, which i guess is based on what team BF has found to work for most though.
You mentioned I term wind up. How is this something to avoid? I may have recently experienced this. How can I combat that happening. I did a normal flip and I just kept flipping till I landed in a snow bank :)
Hi, this makes me think about the TPA and I haven't seen you mentionning it yet (I haven't seen all the tuning videos though). But shouldn't it be systematic that you start any tuning session by removing it entirely, tune the copter and then when you know when the problems appear chose the threshold and the gain accordingly ?
More than to ask what to set, my point was more on the tuning methodology for the quest of the perfect tune. Default TPA might hide some things, maybe it's not required at all in some cases. (?)
I did see it in the features list 3.1.7 and I enabled it. Does that mean it is on all the time now? Also, now it is not in the modes tab anymore. How do I change it back to having it in the modes tab where I can turn it on and off? Thank you very much Joshua for all the time and effort you put in to educate others. Your channel is invaluable.
Question for you - is there a duration that is configurable? If so, and if not, what is the duration at stock? and does the duration change in accordance with something, or is it always the same duration? Thanks - great video!
Joshua Bardwell Sorry - Ok, so this activates via threshold - 30 lets say. That threshold is met, and now AG activates. What is the duration of that activation? Is it a period of time that is dependent on change, or is it activated for a predefined period - say 200ms? Hopefully that explains it better.
I don't know the answer to that. Maybe Boris will notice and answer. Presumably it lasts at least until the throttle stops exceeding the threshold, and hopefully a little longer.
Josh do you have a beta flight video for noobs by chance? I know nothing about it and it's all seems to technical, I just picked up a Turnigy Evolution and Bat QX105 , got them to bind, but it feels weird
Thanks for a great video. I have only one question, not exactly concerning the subject of your video, but still about something you mention here. My quad sometimes suffer from I term windup, even if I set my anti gravity gain at 1. I wonder if you ever made a video about it or did you mentioned some other cases why I term windup can occur. I try to watch all your videos but I might missed that topic. Thank you very much.
My I gain was 35, I soft mount my flight controller, my anti gravity gain was set to 1, I run latest betaflight, the fc is spracing f3 with gyro set to 1khz and pid loop set to 1khz, escs are ZTW flash 30A running on multishot (synchronized with pid loop), motors are emax rs2205 2300kv and prop gemfan 5045HBN. My rates are giving 1100 deg/s at extreme rolls and flips. The disaster while the copter was keeping flipping happened a few times always after extreme flip or roll. Thank you very much for the response. I wonder if I term windup can occur only if there is an excess I gain or because of other factors.
I found one odd thing in my pid settings of the quad that suffered from I term windup: P gain was higher than I gain (25 vs. 35). I changed it and now the P is higher and and after 8 heavy flipped and rolled flights I can say that the problem is gone. Thank you.
Hey Josh. Have a setup that runs perfectly except for huge pitches after punchouts. Pids are default, and I've tried rasing the I gain to 100 but nothing happened. Anti_gravity_gain has no effect on the quad either. Please help, it's almost impossible to powerloop.
I looked under the release notes. I found this: "Airmode is now fully disabled when feature or mode not engaged. Before airmode was always active and it was just the iterm not being active on low throttle." Enabled airmode and it flies like a dream again. Thanks!
Is it possible to see the effects of anti-gravity in blackbox? And what would it look like? Or is the I-term currently logged before anti-gravity is applied?
You can't really see it in blackbox, no. I asked if they would add a marker in the log when antigravity kicks in and out... maybe they will do it. All it will loook like is a change in the I term behavior but you'd be hard pressed to notice it.
its great : ) really solid set at anti_gravity_gain = 2.000 but i usually cut throttle fast when i roll flip.. doesn't I-term become a issue then when Anti gravity gain gets active?
thanks for the information bout anti gravity mode on betaflight.. i'll try to used it..im kinda beginer in making flip/rol ext.. becouse i never used air mode..it kinda complicated when my quad crash or forgot to turn off when landing
what beta-flight option should i tune if i see that my quad drops attitude a lot when i pitch forward and backwards or roll ? i find myself straggling to keep it at it attitude.
@@JoshuaBardwell as a side note i wonder why there is no special option that auto add as needed when such moves accrues to address such issue where you you need to raise the throttle just to keep the quad leveled...
So to be perfectly clear, the threshold controls how 'far' the throttle needs to change over a fixed (100ms) amount of time right? I could maybe see this needing to be lowered on high power to weight quads where < 35% throttle change results in more overall change in thrust. And maybe increased for those under powered quads where 35% change in not really a punch out. But I can see 35% working most of the time.
Yes that's right. If you have a quad where you don't move the throttle much, then possibly you do want to change the threshold. The thing is, if you are not exceeding the threshold, then the gain will never kick in. So if you raise the gain and raise it and raise it and nothing changes, the maybe the threshold needs to be lowered.
Anti gravity was turned off on my kopis 1 from the factory tune, should i turn this on? Should i be using it? and if so what should i set it to? When going full throttle with a fresh battery the kopis 1 would flip around (yaw and flip) automatically on angle mode with right stick centered, the out of control feeling would last about 3 second then straighten itself out. I am using 1550 HV batteries when the voltage comes down a bit it doesn't seem to do it... very strange. Joshua can you please do a video of ultimate settings for the Kopis 1 just on config and PID tabs in betaflight.
Sooo... Even when antigravity gain is set to 3 and I is set to 130 on pitch and 100 on roll my quad won't stop pitching like crazy on punch outs. Also, when I go to idle, it feels veeeeery sluggish as if I gain is way too low. And my Idle is very high! I could get it lower, but then it becomes unflyable. I've tryed to fix this for a long time, but it won't go away. With those high gains it works better, but still not good. I'm running a Hyperlite F4 with BF 3.1.7 at 8/8/8, T Motor F40 pro 2400kv and Littlebee Blheli 30a esc. So the esc are the only thing i haven't switched out since I build my first 4s setup, so they are the last possibility of a hardware error. Can this be caused by the old Blheli? Is it slower or not as powerful on low throttle compared to Blheli_s? Because I see so many well working setups on yt, but all have Blheli_s... Maybe you can help me there :) And thanks for reading!
thanks for explaining the antigravity.. so i messed around and got my old hyperlite f4 to work again and since its revo i put newest frimware 3.1.7 im worried about it losing its memory again but dont know until i try it. Have u ever heard of a flight controller losing all settings and going default when pluggin fresh lipo in?
I've been struggling with pitch attitude hold, on my builds since moving from 2300kv to 2600kv. For racing, and the constant throttle adjustments, can you address any potential initial setting deltas? thanks
Joshua, thanks. I recently flashed two of my quads with 3.16 and yesterday evening I set the anti_gravity_gain to 2.0 and it worked like a charm. What an awesome feature.
Is there a solution for this on KISSFC? I mean using KISS FW. I just installed new ESCS and my quad is still pitching up severely under heavy throttle.