What is the point of tuning PIDs?
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Cyberdactyl
Misfit Multirotor Monkey
I agree, however IMHO designing and tuning firmware to make it stable but not stable enough to arouse large amounts of suspicion would be harder than flying the quad smoothly itself
I suppose it could be less obvious if the transitions where smooth, but a finely or poorly tuned mini quad doesn't have much control over the basic physics of having to pitch forward ..or back.. during hard accelerations and/or WOT. Editing out those transitions would help immensely mask a servo-assisted cam.
zenguerilla
Senior Member
Gradual constant elevator should send the quad 'slipping' through the air. Half 'flying', half falling... forward. PIDs.
Cyberdactyl
Misfit Multirotor Monkey
Right, as in 'smooth transitions'.
But that doesn't get around a WOT full tilt. The z axis still has to pitch way forward. And in contrast, a hover the z axis is pointed straight up. No way around the transition . . at least. . . for the common multirotor.
My guess is the quad in "FPV Practice Laps in 60fps" is maintaining about a 25 forward pitch virtually throughout the entire run going ~31mph.
But that doesn't get around a WOT full tilt. The z axis still has to pitch way forward. And in contrast, a hover the z axis is pointed straight up. No way around the transition . . at least. . . for the common multirotor.
My guess is the quad in "FPV Practice Laps in 60fps" is maintaining about a 25 forward pitch virtually throughout the entire run going ~31mph.
zenguerilla
Senior Member
Who says he needs or uses WOT, which incidentally only puts the quad up... not forward.
Cyberdactyl
Misfit Multirotor Monkey
zenguerilla
Senior Member
LOL... nice one Cyber.
Elevator is not throttle... LOL
It's just pasta... north china, or japan (not soba), style ... well, southeast asia, etc. uses them (culinarily) too...
edit: between that and the cramps, looks like the matrix has a 'gut' in mind for me...
ehh... nevermind the bollocks...
...call it a buddah belly
Elevator is not throttle... LOL
It's just pasta... north china, or japan (not soba), style ... well, southeast asia, etc. uses them (culinarily) too...
edit: between that and the cramps, looks like the matrix has a 'gut' in mind for me...
ehh... nevermind the bollocks...
...call it a buddah belly
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Zenguerilla, sounds like you havent dont much acro flying or high speed flying. If you are flying at non trivial speeds (and thus angles), throttle will control speed. And in acro you dont keep applying forward elevator .
As for Ummagawd's supposed gimbal; he is using a (very) wide angle lens, which makes pitch movements less obvious.
.As for Ummagawd's supposed gimbal; he is using a (very) wide angle lens, which makes pitch movements less obvious.
pungbjoern
Senior Member
Lots of good information here. I currently only fly LOS, actually. I got in to this hobby to fly fpv, but I feel like I need to become a better LOS pilot before I get in to FPV. I get that you *should* tune your PIDs, but I wasn't clear on if there was another reason other than "to prevent it from behaving badly". Now I know there are as many opinions as there are people =)
I'm personally more interested in tuning *rates* than PIDs, but that might change in the future. I've yet to see any downsides with the custom PIDs, which is likely why. I've seen plenty of downsides with the custom rates (which are all 0 for all pid controllers in cleanflight, it seems). I also currently only fly horizon mode. That, too, might change, but likely won't for a while.
I'm personally more interested in tuning *rates* than PIDs, but that might change in the future. I've yet to see any downsides with the custom PIDs, which is likely why. I've seen plenty of downsides with the custom rates (which are all 0 for all pid controllers in cleanflight, it seems). I also currently only fly horizon mode. That, too, might change, but likely won't for a while.
I had a similar problem when starting with my Anycopter quad. It flew "nicely" with the standard KK2.1.5/Stevie's firmware without any optimization.
But after I started playing with the settings and trying to get the PIDs right, it was a so different feel to the quad. The flying is a lot easier too if the quad is quick and precise if you need it.
I don't like to fiddle around with those settings though. It can be tedious. My solution? A TauLabs controller with autotune ;-)
But after I started playing with the settings and trying to get the PIDs right, it was a so different feel to the quad. The flying is a lot easier too if the quad is quick and precise if you need it.
I don't like to fiddle around with those settings though. It can be tedious. My solution? A TauLabs controller with autotune ;-)
Oh, Sure, throw money at the problem
(he says as he secretly curses his new cheapo CC3D board and the crappy OP that won't tune to anything nice between drunken sailor and Coffee addict with DT's . . . all while researching the to move to Tau )
Oh, Sure, throw money at the problem
(he says as he secretly curses his new cheapo CC3D board and the crappy OP that won't tune to anything nice between drunken sailor and Coffee addict with DT's . . . all while researching the to move to Tau )
Do it! The latest Tau build for CC3D supports autotune again
I keep hoping a CC3D will fall into my lap so I can try Tau on it and help people make the jump. They're so cheap I'd pick one up myself at this point...but I just can't bring myself to put any money into a F1 based board anymore I've already got more FC's and ESC's than I do motors too so again just can't justify even $15 on one. Though it sounds like thanks to another forum member I may be getting some more motors soon and be able to put some of these spares to good use finally
Probably not what you're hoping to hear but...
If your primary goal is to fly FPV I'd say jump right to it as soon as you've got the basics of LOS down. FPV is so different that good LOS skills don't really seem to help much. They don't hurt, but I still struggle with FPV even though I feel very confident flying LOS now.
Also it does sound like rates/expo are more what you're looking for...but...having a good PID tune is still the foundation to build from as great rates with a poor pids will always fly worse than great pid's with poor rates. That doesn't mean you need to spend a ton of time trying to get the PID's "just right" but it does mean they should at least be "pretty darn good" before you focus on rates.
And, as someone who loves horizon I have to say...set it aside it will only hold you back. Especially if you want to fly FPV. Rate is scary, I know, but it really is a necessary skill for what it sounds like you want to achieve. And it's a lot easier to learn rate from the start than it is to break the habits that go with a self leveling mode and learn rate later. I made that mistake myself and it's the one biggest thing I'd change if I was to start over today. Thankfully with CF mini's it's a lot harder to damage them in crashes than it was with the wooden quad I started with which was why I kept going back to horizon!
I'm in the same boat as jhitesma. Do yourself a favor and turn horizon mode off unless you are flying in a place where you dare not crash.
The faster and harder you fly, the more PID tuning will matter. Where you are today, it's fine to fly with stock PIDs. If you keep pushing, someday stock won't be enough.
The key is to keep pushing.
The faster and harder you fly, the more PID tuning will matter. Where you are today, it's fine to fly with stock PIDs. If you keep pushing, someday stock won't be enough.
The key is to keep pushing.
RandomChaos
New member
Do it! The latest Tau build for CC3D supports autotune again
Wait, I can put Tau on my CC3D? Don't fail me now Google!
pungbjoern
Senior Member
My goal is to be able to perform a slow banked sweeping figure 8 in horizon mode before moving on to acro mode. This is something I mastered on my Blade Nano QX, after which I started flying it in acro mode. I didn't have a chance to master it on my 450 before it flew away. I did have a chance to master it on KK with my 250, but then I switched to the naze, and now I have to re-learn again. No doubt I'll get there. It'll just take time.
With my new frames in the mail, I'm going to institute a new policy. I'm going to fly 1 pack every day (weather permitting) before breakfast. They say practice makes perfect, and it's the only time the park behind my house isn't lousy with kids and parents...
As to "a place where you dare not crash", that'll be "my wallet". I went through 10 props for 8 packs the other day tuning my rates and trying CF pid controllers 1, 2, and 3. The ground is surprisingly unforgiving in my park... =( It also doesn't help that, because if it's size, I have to fly 1-2 meters above ground. If I spent all my time 10 meters in the air, I can imagine I wouldn't hit the ground quite so often.
I guess I just have to find someone with sufficiently similar gear, copy their pids, then start flying. Or continue flying, rather.
TL;DR: I'll get to acro mode eventually. =)
With my new frames in the mail, I'm going to institute a new policy. I'm going to fly 1 pack every day (weather permitting) before breakfast. They say practice makes perfect, and it's the only time the park behind my house isn't lousy with kids and parents...
As to "a place where you dare not crash", that'll be "my wallet". I went through 10 props for 8 packs the other day tuning my rates and trying CF pid controllers 1, 2, and 3. The ground is surprisingly unforgiving in my park... =( It also doesn't help that, because if it's size, I have to fly 1-2 meters above ground. If I spent all my time 10 meters in the air, I can imagine I wouldn't hit the ground quite so often.
I guess I just have to find someone with sufficiently similar gear, copy their pids, then start flying. Or continue flying, rather.
TL;DR: I'll get to acro mode eventually. =)
Did you see the Lux Float PIDs that FGA gave to Narco that I used on my tri-copter?
Those should get you in the ball park and are likely better than stock.
When I crash at home, I hit the vegetable garden or one of my wife's flower gardens which are mined with invisible (to an FPV cam) tomato cages. I fly in horizon mode a lot at home. Rotors are expensive. Cutting down Bobbi's roses costs me a trip to the jewelry store...
The F1 on the CC3D is really being pushed hard with Tau. Did you share your autotune results on the Tau forum? What kind of noise values were you seeing? It could be the processor just isn't keeping up well enough to actually tune properly. I know when I got Tau going on my Naze I was able to run autotune - but the results were unusable and it appears the reason is the processor just couldn't keep up
But that was on freeRTOS and CC3D has been updated to ChibiOS which is more efficient which is why they were able to bring autotune back on that target.What values were you using for damping and noise sensitivity when setting up autotune? You may want to turn down damping a bit and turn noise sensitivity up a bit to get more responsiveness. As the hints on the autotune page say lower damping values give quicker response while higher values give more stability, and higher noise sensitivity values can give faster response but go too high and you'll get twitches.
And it's still classified as "experimental" though so far it seems most people are having good results with it. It does seem that smaller setups and 5" props are more likely to run into issues...but that's just me drawing conclusions from too small of a data set
I usually touch up my tune a bit after running autotune because it's not prefect. But on my hex I've been flying with default autotune settings because it "just worked" on there and I've been very happy with it.
Do it! The latest Tau build for CC3D supports autotune again
I noticed that -- My goal for moving to Tau is to get to a better PID controller, but I won't turn my nose up at an auto-tuner, so long as it works
I'd picked up the CC3D for the current build primarily to play with a "popular" controller (since it's becoming VERY common alternative to the KK2's and Multiwii's in the cheapo kits). Can't give precise advise if you haven't played with it yet . . . and the Tau and Cleanflight ports still make it an interesting board to learn.
Reflashed to Tau and walked through the setup over lunch, but that was all I could get to. Seemed to respond better to the GCS than the stock OP did . . . which I haven't decided if it was unnerving or encouraging . . . but in an hour or so (after work) I plan on testing her legs on the new ROM.
We'll see.
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