Manual Mode Control Question

[Chaosrider@brilliantfrogs]

Manual mode feels pretty natural at this point...not all the way there, but closer.

My question is about the control balance at high speed, 80+ mph. I can get it up to about 83 mph pretty reliably at this point, with comfortable control...except for altitude.

With both sticks full forward...max throttle, max downward pitch...the aircraft continues to climb. Is that normal? Is max speed obtained at less than max power, due to a pitch limitation?

If that's the case, that's fine, but I'm wondering if there's something that I'm missing. In piston powered fixed wing airplanes, you always get max speed at max, power, straight and level, but I'm perfectly willing to believe the FPV isn't like that.

Thoughts?

Thx.

 

[Kilrah]

There is no "max downward pitch", if you hold the pitch stick forward you'll do endless front flips. Unless you haven't disabled the angle limit that is, so it seems like that's your issue.

 

[rktman]

There is no "max downward pitch", if you hold the pitch stick forward you'll do endless front flips. Unless you haven't disabled the angle limit that is, so it seems like that's your issue.

And probably why an understanding of "rate mode" appears to the rest of us to not be sinking in. Explains a lot.

 

[Chaosrider@brilliantfrogs]

There is no "max downward pitch", if you hold the pitch stick forward you'll do endless front flips. Unless you haven't disabled the angle limit that is, so it seems like that's your issue.

I'm still in "restricted" Manual mode. It did occur to me that I may be bumping against a limit imposed by that, rather than a limit of the drone capability itself.

Still, I can cruise at 82 mph with things as they are. Given my actual Mini-2 performance at my elevation...about a mile up...compared to the published spec, it's hard to expect I'd get more than another couple of miles an hour on speed by going to the final "control release" step to get into "full" Manual.

Assuming that's the issue that I'm seeing, and it makes sense that it could be.

Assuming this is the case, I'll just do some additional testing to see what throttle setting will produce 80+ mph in level flight.

Thx!

Thx.

 

[Chaosrider@brilliantfrogs]

And probably why an understanding of "rate mode" appears to the rest of us to not be sinking in. Explains a lot.

(sigh)

I had the right stick pushed full up for a sustained period of time, and after a while, it wouldn't tilt any farther down, or go any faster. It just gained altitude with increased power.

I wasn't expounding on any grand engineering or aerodynamic theory. I was reporting on an observation that seemed odd, looking for an explanation.

That has nothing to do with me not understanding negative stability, which I have for many decades.

 

[Chaosrider@brilliantfrogs]

What's the max speed that any of you have seen in level flight, and at what MSL elevation?

Assuming ya'll ever do level flight...

;-)

 

[Kilrah]

In metric the display won't display values above 158km/h, that's 100mph so... more than that but can't know. Probably wasn't level though.

 

[Chaosrider@brilliantfrogs]

In metric the display won't display values above 158km/h, that's 100mph so... more than that but can't know. Probably wasn't level though.

So you've seen 100 mph in level flight? They only advertise 87 mph.

 

[rktman]

(sigh)

I had the right stick pushed full up for a sustained period of time, and after a while, it wouldn't tilt any farther down, or go any faster. It just gained altitude with increased power.

I wasn't expounding on any grand engineering or aerodynamic theory. I was reporting on an observation that seemed odd, looking for an explanation.

That has nothing to do with me not understanding negative stability, which I have for many decades.

(Sigh) If you understood Rate Mode you would never hold the right stick full forward like you did to fly straight forward– ever. Period. If you understood, you would immediately see the gross error in such a control move. And how it would put you wildy out of control.

You've been flying manual with training wheels. You can not achieve the FPV's top speed with attitude restriction enabled, because you have to pitch forward more than it will allow. That's why you were climbing.

However, you are clearly getting annoyed and pissed, and think you do understand, and have become closed to my honest attempt to help, so at this point I will sincerely wish you luck, and leave you to get help from others.

 

[rktman]

What's the max speed that any of you have seen in level flight, and at what MSL elevation?

Assuming ya'll ever do level flight...

;-)

96mph, 50', right stick centered with tiny pitch input to control and maintain altitude. Throttle at max.

Edit: before you ask, tailwind

 

[Chaosrider@brilliantfrogs]

(Sigh) If you understood Rate Mode you would never hold the right stick full forward like you did to fly straight forward– ever. Period. If you understood, you would immediately see the gross error in such a control move. And how it would put you wildy out of control.

You've been flying manual with training wheels. You can not achieve the FPV's top speed with attitude restriction enabled, because you have to pitch forward more than it will allow. That's why you were climbing.

However, you are clearly getting annoyed and pissed, and think you do understand, and have become closed to my honest attempt to help, so at this point I will sincerely wish you luck, and leave you to get help from others.

Pissed is way too strong a word. Annoyed is closer, but the best word is probably...exasperated. It seems like we've been speaking different languages for much of these exchanges.

Sometimes, I've felt more like I was being "preached at", rather than "explained to"...

I said all along that I was still in the "restricted" Manual mode. If the drone had started to go "wildy out of control" when I pushed the right stick full up, I'd have punched out and gone back to Normal mode. Nothing like that happened. So when you say with certainty that something will happen, and then nothing like that happens, it can be...confusing.

You can not achieve the FPV's top speed with attitude restriction enabled, because you have to pitch forward more than it will allow. That's why you were climbing.

That was my best guess for what had happened. I suggested that as a possible explanation. Would it have been so hard to have just said that, without the...wrapping?

My remaining question is, how much faster might I actually go by switching over to "full" Manual mode? Straight and (preferably) level, I can get 82-83 mph reliably as-is. If full Manual would only get me a couple more mph, it's not clear that I want to do that. Which is not to say that I won't, eventually.

and have become closed to my honest attempt to help, so at this point I will sincerely wish you luck, and leave you to get help from others.

Perhaps I wasn't the only one getting exasperated...

;-)

I'm not the least bit closed to your attempts to help, I greatly appreciate them! And, questioning advice does not imply that the advice isn't valued.

96mph, 50', right stick centered with tiny pitch input to control and maintain altitude. Throttle at max.

Edit: before you ask, tailwind

When I first started engaging in these conversations a year ago, it wasn't immediately obvious to me that the speed that gets displayed is ground speed, not air speed. But eventually the light dawned. Another misleading carry-over from my fixed-wing flying.

In a way, this is a lot like the fact that the altitude that gets displayed is ATL, rather than AGL, which is what I really want. I'm far more interested in airspeed than ground speed.

But it is what it is, and I get the in-flight data that I get. Life goes on! In this particular case, much of my Manual mode flying has been in zero or light wind conditions, which was fortunate.

Thanks. Really!

 

[rktman]

All along I've simply been trying to help. I feel a bit of kinship with you, being same generation, private pilot experience, where you live, what kind of personality you come across in your sharing your experiences. I'm a retired engineer/scientist, we seem to have many interests in common – big Trek fan too (watching Strange New Worlds? Love it!)

I'm trying to help you. You challenged @Kilrah and me that we can't know what you understand. Fair enough. But we can analyze and judge what you say about your understanding, and it is dangerously wrong. No exaggeration.

If you simply can't accept that I know enough to make that evaluation, then all I can do is wish you luck and hope you get your understanding adjusted some other way.

I'm trying to save you from catastrophe. If you need to actually experience for yourself how wrong you are in order to believe it, remove that angle restriction, head up to 400', then push both sticks forward like you did before and hold them there. Be ready on the brake, and come back and let's discuss what rate mode is. Let's also hope disorientation didn't delay that brake.

Rate mode has absolutely nothing to do with the rate of attitude change due to negative dynamic stability. Saying this is like saying the throttle controls EV for the camera.

I'm willing – want to – keep helping you. But it seems you've closed your mind to being wrong about some things that you are in fact very wrong about.

Take that angle restriction off and go do your Canyonball run the same way as before. That will clear things up, and then we can get somewhere on what Angle Mode and Rate Mode mean.

Or, I can sideline, as I was going to, and you can work it out without my input. I'm good either way. I'd hate to see you blow up your FPV, especially after being the biggest cheerleader for you getting one, but it's not worth poisoning a new friendship in this hobby.

 

[Chaosrider@brilliantfrogs]

All along I've simply been trying to help. I feel a bit of kinship with you, being same generation, private pilot experience, where you live, what kind of personality you come across in your sharing your experiences. I'm a retired engineer/scientist, we seem to have many interests in common – big Trek fan too (watching Strange New Worlds? Love it!)

Yes, in many ways it appears that we were separated at birth!

I'm trying to help you. You challenged @Kilrah and me that we can't know what you understand. Fair enough. But we can analyze and judge what you say about your understanding, and it is dangerously wrong. No exaggeration.

Dangerous how? I mean that as a serious...and specific...inquiry, not as a (Mod Removed Language) comment.

Part of my problem is the number of forecasts of disaster that have been made for me already, that have not come to pass. In 10 Manual mode flights now, I've had one...one...crash, on my second flight, which resulted from over confidence, and ignoring the "punch out" process that I had already established.

The damage was minimal, and the Beast flew again that day. Lesson learned. Cheap lesson learned.

Just to clarify the way it looks from my side, if a process repeatedly forecasts disaster, and it never happens, that tends to reduce my confidence in that process.

Could it be that I've just been lucky? Perhaps. People have said that I'm unusually lucky all my life. Maybe they're right. Or maybe Obi Wan was right...

I'm trying to save you from catastrophe. If you need to actually experience for yourself how wrong you are in order to believe it, remove that angle restriction, head up to 400', then push both sticks forward like you did before and hold them there.

This may point to part of the source of our misunderstanding.

What gives you any reason to believe I'd do that? My progress has been slow and incremental all along. I very consciously decided that I was going to treat Manual mode as a different aircraft, and that's what I did. I didn't, suddenly and willy-nilly, push the sticks forward. I had been gradually increasing the control deflection all along, and I only pushed the right stick all the way forward because pushing it forward had ceased to make a difference.

I've been slowly and incrementally approaching the FPV all along, from an extended period in Normal mode, then in Sport mode, and now in Baby Manual. Why would you think I would suddenly make severe changes when/if I switch to Full Manual? That's completely contrary to everything that I've said, done, and reported.

I expect that Full Manual will be very different from Baby Manual, just like I fully expected Baby Manual to be very different from Sport.

Rate mode has absolutely nothing to do with the rate of attitude change due to negative dynamic stability. Saying this is like saying the throttle controls EV for the camera.

I'm looking for verbal handles to describe observations, and you're looking at theory. The concept of negative stability...not the details of the mechanics...goes a long way to describing what I've seen.

It's not precise. Maybe it's ultimately wrong. I rarely care about precision early in any process. I'm an incremental guy.

Perhaps this (true) story will help. One time when I was putting in budget a request for a big new project as CIO for Nevada, I told the Budget Director that I intended to spend about $50K on a prototype, and then throw it away. He got as white as a sheet. When I explained how the Rapid Prototyping variant of the Agile class of methodologies worked, he fully understood...and suggested that I not describe the process to the legislature that way, which I didn't.

The point of that is that I really don't care if I develop a model of something early, that I later have to purge entirely. I have no obsession with being right. I have no fear of being wrong. I will be wrong. I plan on being wrong. Being wrong, and re-booting my understanding as needed, is how I learn.

Being wrong is a feature of how I learn, not a bug! In my experience, it's much faster that way, than trying to get everything right on the first pass. YMMV.

I'm willing – want to – keep helping you. But it seems you've closed your mind to being wrong about some things that you are in fact very wrong about.

See above. Being wrong doesn't bother me at all. But asserting that I'm wrong...even if correctly so...is very different from explaining why.

I've had very limited faith in experts since I was told that I was one, and that was over 20 years ago...

;-)

Take that angle restriction off and go do your Canyonball run the same way as before. That will clear things up, and then we can get somewhere on what Angle Mode and Rate Mode mean.

Doing that would be completely contrary to everything I've said, done, and reported since before my first FPV flight. What would make you think I'd do that?

Or, I can sideline, as I was going to, and you can work it out without my input. I'm good either way. I'd hate to see you blow up your FPV, especially after being the biggest cheerleader for you getting one, but it's not worth poisoning a new friendship in this hobby.

I'd much prefer that you stay engaged!

Perhaps what I've said here clarifies my perspective a bit. I have no problem being wrong. I plan on it, but I need to have it explained to me why I am, before I'll change my model.

If nothing else, this is my most long-winded post ever! It had to happen sometime, and now it's done...

Chill!

 

[rktman]

If you're open to explanation, I'd be happy to explain why angle limited rate mode can totally fool you into believing you understand rate mode coming from experience flying angle mode, and how it protected you from yourself rather than you developing real muscle memory and instinct for the very different way the aircraft responds to control stick movements.

You are successful because of the attitude limit. Remove that, and I guarantee you you will no longer be able to fly that thing the way you've been flying it. With it you will not be able to max the FPV's speed.

One simple explanation that may be enlightening: Remove the attitude restriction. Make no other changes. Go to 400'. Get yourself lined up, and accelerate to where both sticks are held full forward, like you did before.

Here's what will happen: The aircraft will flip over forward, a full 360°, at a frightening rate, something like 2-4 flips per second. Your view will be incomprehensible and disorienting. Knowing where the aircraft is, height, let alone control it will be completely impossible. The reason you are doing this experiment at 400' is so you will have a second or two to hit that brake, God Bless DJI

Is that what you imagine happening?

 

[rktman]

Dangerous how? I mean that as a serious...and specific...inquiry, not as a (Mod Removed Language) comment.

Part of my problem is the number of forecasts of disaster that have been made for me already, that have not come to pass. In 10 Manual mode flights now, I've had one...one...crash, on my second flight, which resulted from over confidence, and ignoring the "punch out" process that I had already established.

You have DJI to thank for that, on two counts: The brake feature, and the attitude limit training wheels.

If you were doing this with just about any other FPV quad, every one of those brake hits you talked about during your first few flights would have been a crash (maybe not every one, but you get the point).

Starting out as a complete novice without that attitude angle limit would with certainty resulted in more, and more frequent loss of orientation and control, and with no brake, another crash.

So watch out for overconfidence when the system is still providing critically important safety guardrails. You're kind of flying half-manual and rather than helping you transition, it's teaching you some bad habits, wrong ideas about how the whole thing works and the control dynamics.

All of this is much much easier to understand by experience rather than the far lower fidelity means of written communication. That's why your friends here really advocated for sim time first (I have Velocidrone), where you can crash and burn – I mean learn

 

[Chaosrider@brilliantfrogs]

If you're open to explanation, I'd be happy to explain why angle limited rate mode can totally fool you into believing you understand rate mode coming from experience flying angle mode, and how it protected you from yourself rather than you developing real muscle memory and instinct for the very different way the aircraft responds to control stick movements.

I completely believe that the angle limiting feature has had protective value. That's why I've continued to use it!

But I see at least two possible meanings from this. Does the Full Manual mode behave the same way Baby Manual does, except for the absence of the angle limitations? Or does it behave fundamentally differently prior to reaching the angel limitations?

You are successful because of the attitude limit. Remove that, and I guarantee you you will no longer be able to fly that thing the way you've been flying it. With it you will not be able to max the FPV's speed.

Every time I've gone to a new mode, I haven't expected it to be like the old mode. Why would I view it differently for the transition from Baby Manual to Full Manual? Assuming I ever do that...

I would expect it to be different, and experimentally expand my envelope incrementally, not suddenly and willy-nilly.

One simple explanation that may be enlightening: Remove the attitude restriction. Make no other changes. Go to 400'. Get yourself lined up, and accelerate to where both sticks are held full forward, like you did before.

Why would I do that? Why wouldn't I make small incremental changes in my control inputs, as I've done every time I've changed modes so far?

If I were to change to Full Manual, I'd go back up to my 350 ft starting point, and timidly move down the canyon to make sure it was controllable, with my trigger finger poised on Brake button. Neither stick would be anywhere near full deflection on those first runs.

Why would they be?

Here's what will happen: The aircraft will flip over forward, a full 360°, at a frightening rate, something like 2-4 flips per second. Your view will be incomprehensible and disorienting. Knowing where the aircraft is, height, let alone control it will be completely impossible.

I don't get disoriented easily. And if I did, I'd hit the Brake immediately, and do less of what I did leading up to that, for the next pass.

Why in the world would you think that I would start learning a new mode with full control stick deflection? That would be totally out of character, and inconsistent with everything that I've done so far.

God Bless DJI

Amen to that!

Is that what you imagine happening?

Uhhh...sure, why not?

I hadn't really imagined it at all, since it never would have occurred to me to start learning a new mode by using full stick deflections.

You have DJI to thank for that, on two counts: The brake feature, and the attitude limit training wheels.

Sure. Those both exist, and I've done what I've been doing fully aware of that.

I work with what I've got...

If you were doing this with just about any other FPV quad, every one of those brake hits you talked about during your first few flights would have been a crash (maybe not every one, but you get the point)

Sure. I've never had the slightest interest in traditional-crazy FPV.

Perhaps, that's why I bought the DJI FPV, rather than a traditional-crazy FPV.

You think?

Starting out as a complete novice without that attitude angle limit would with certainty resulted in more, and more frequent loss of orientation and control, and with no brake, another crash.

I'm a published science fiction author. What do you wanna bet that I can create counter-factual alternate realities faster than you can...?

;-)

If things were different, they wouldn't be the same as they are.

Now I've paid my dues to the Tautology Club for the week!

Bonus!

So watch out for overconfidence when the system is still providing critically important safety guardrails. You're kind of flying half-manual and rather than helping you transition, it's teaching you some bad habits, wrong ideas about how the whole thing works and the control dynamics.

Perhaps, I have less of an attachment to my early incremental ideas and habits, than you think I do.

If the system behaves differently, I'll adapt, like any good Borg. I don't form strong attachments to my early understandings, or ways of doing things.

All of this is much much easier to understand by experience rather than the far lower fidelity means of written communication.

Oh, I completely agree with that!

That's why your friends here really advocated for sim time first (I have Velocidrone), where you can crash and burn – I mean learn

Which I would have happily done, if it had been conveniently available in my Droid infested world.

Who knows? Maybe I'll do it anyhow, before going to Full Manual. If I ever do...