DJI FPV -- Initial Stick Adjustments for Transition

[Chaosrider]

I'm transitioning to Manual mode with the FPV this week, and I want it to be a nice gradual process.

How much "stickiness" and "centering" of the sticks do you recommend for initial Manual mode flights? The primary objective of the first flights is simply not crashing, rather than testing out all of the capabilities.

I read the FPV manual, and I understand the adjustment process, but I have no clue which settings would be optimal for transitioning. I'll re-read it again before doing it, of course, but advice from experience would be greatly appreciated!

Thx.

 

[EpicFlight]

Don't change the right stick at all.

Remove ALL springiness return to center from the left stick. Adjust the friction to where you like it, the objective is for the throttle to stay where you want it, only changing with pressure from you.

Practice that BRAKE button 5000 times at at least 150' AGL as your first exercise.

 

[Chaosrider]

Don't change the right stick at all.

Remove ALL springiness return to center from the left stick. Adjust the friction to where you like it, the objective is for the throttle to stay where you want it, only changing with pressure from you.

Practice that BRAKE button 5000 times at at least 150' AGL as your first exercise.

OK, good! That confirms some of my impressions.

It wasn't obvious to me at all why I'd want to change the right stick, so I won't.

I definitely want the throttle to stay where I put it, but I also want it to be fairly easy for me to put it in a different place if I want to do that. I seem to recall there are adjustments for both of those.

Remind me...what does left-right movement of the left stick do in Manual mode?

The brake button practice was already high on my list. Why do you suggest at least 150 ft AGL? Recovery time, I guess. But if I am going to crash into the sagebrush, I'd rather do it from 50 ft AGL, than 150 ft AGL. But maybe that doesn't matter for damage limitation.

I've actually gotten pretty good at hitting the brake button, since I need to use it all the time to cancel lost signal RTH, or low battery RTH...

Thx!

 

[EpicFlight]

All the stick movements control the same aircraft behavior, L/R on left stick controls yaw rate, U/D throttle. However, throttle behaves differently, in that you will be adjusting it for both speed and elevation in combination with right stick pitch.

Right stick still controls pitch and roll like before, but they control the rate of change rather than the angle. The way this feels is quite different.

So, to go faster, you give it some forward/up right stick, for a bit, then let re-enter. this will pitch the drone further forward, then when you recenter the stick it will hold that increased pitch angle.

By doing that it will speed up, 'cause more power is pushing forward than before. But that means less is countering gravity, and you start to lose altitude. So, at the same time your pitching forward, you need to increase the throttle to hold altitude.

THAT'S why you want to experiment at high AGL... you can lose orientation and control in a heartbeat when new, and you want to give that brake plenty of room to level/stop/hover while you're learning.

 

[Chaosrider]

All the stick movements control the same aircraft behavior, L/R on left stick controls yaw rate, U/D throttle. However, throttle behaves differently, in that you will be adjusting it for both speed and elevation in combination with right stick pitch.

Right stick still controls pitch and roll like before, but they control the rate of change rather than the angle. The way this feels is quite different.

So, to go faster, you give it some forward/up right stick, for a bit, then let re-enter. this will pitch the drone further forward, then when you recenter the stick it will hold that increased pitch angle.

By doing that it will speed up, 'cause more power is pushing forward than before. But that means less is countering gravity, and you start to lose altitude. So, at the same time your pitching forward, you need to increase the throttle to hold altitude.

THAT'S why you want to experiment at high AGL... you can lose orientation and control in a heartbeat when new, and you want to give that brake plenty of room to level/stop/hover while you're learning.

OK, this is starting to make a bit more sense. I'm trying to visualize actual stick movement to produce actual aircraft movements.

My first Manual mode flight, probably tomorrow, will involve lifting off to about 4 feet above the ground, doing a full 360º rotation, then going down to the end of the driveway (about 100 ft), turning around, and coming back.

Just to check my understanding, in order to do that I would:

1) FIRST QUESTION: How do you start the motors in Manual mode? Sticks down and in just like usual? If yes, how does the tightening of the left stick impact this action?

2) Apply enough power to lift up to 4 ft. Is this a single action that moves the throttle to a specific place, and it then stays there, or do you end up needing to increase power, and then back off, to hover at a specific altitude?

3) 360º rotation. This seems like it will just be a left stick motion to the right or left, as usual. Yes? Is any throttle change involved to do this?

4) Go down the driveway. Per your above, this will be done using a slight forward pitch by moving the right stick up, and a slight increase in power to maintain altitude, to compensate for the thrust that gets diverted to moving forward. Is that right? This part gives me the sense of being like a regular airplane in some ways, and if that's the case, it should be natural for me.

5) Stop at the end of the driveway. Pitch returned to neutral, which it will do on it's own by letting go of the right stick, and decrease power slightly. Yes?

6) At that point, turning around and coming back, then stopping, will just be a repeat of motions that I've already done, but they'll be in "reverse command" with the drone facing me.

For this entire process, I don't expect to exceed 2 -3 mph.

Did I get anything wrong in this sequence?

Thx!

 

[okw]

My first Manual mode flight, probably tomorrow, will involve lifting off to about 4 feet above the ground ...

I don't have the DJI FPV, but I've read plenty of reports of failed attempts to take off in Manual mode. Likely caused by the angle that the quad sits at while on the ground. I'd recommend taking off in Normal mode, then switching to Manual once airborne.

 

[EpicFlight]

If you haven't done some sim time, you MUST before you fly at all in manual. The control behavior is so different YOU WILL CRASH if you don't have hours flying successfully in the Sim without crashing.

Your plan above will, no doubt result in a sad and mad @Chaosrider without his FPV for weeks while it's at DJI getting repaired.

Don't expect to hover in place... you can't. There's no positioning, the thing slides around like a puck on ice, moves around with every breeze. This has a far bigger impact than you think: You no longer have the option to get off the controls, gather your thoughts for a few seconds, and continue. You are "on" all the time.

You will not be taking off aand landing in M any time soon. Taking off, in particular, is quite difficult. Crash, crash crash.

Abandon your camera drone template for incremental learning. When a noob, you don't want to be closer than 100 feet to any object when in M.

So, rethink your plan to bracket M flight with takeoff and landing in N/S mode, and get a good 100' above the treetops before switching to M.

 

[EpicFlight]

1) FIRST QUESTION: How do you start the motors in Manual mode? Sticks down and in just like usual? If yes, how does the tightening of the left stick impact this action?

There is a different motor start procedure in Manual. HOWEVER DON'T TAKE OFF IN MANUAL UNTIL YOU ARE PROFICIENT FLYING MANUAL. You will flip over, lose control, crash, all sorts of bad things. It is really really REALLY hard to take off in Manual.

Take off in Normal, ascend to a good altitude, then switch to Manual to start your learning/practice. It's a little weird with the unsprung throttle, but not too difficult.

2) Apply enough power to lift up to 4 ft. Is this a single action that moves the throttle to a specific place, and it then stays there, or do you end up needing to increase power, and then back off, to hover at a specific altitude?

No, don't do that. 99% chance you will get out of control, revert to reflex, and use Angle mode muscle memory which will send you flying directly into something. Don't spend much focus on yaw -- it's the one thing that works the same. You need to develop your feel for the interaction between throttle, and pitch/roll changes. Do that at altitude.

Big open fields are good places to learn too 'cause you can get a better feel for elevation response to the throttle, being closer to the ground without collision risk.

3) 360º rotation. This seems like it will just be a left stick motion to the right or left, as usual. Yes? Is any throttle change involved to do this?

No

4) Go down the driveway. Per your above, this will be done using a slight forward pitch by moving the right stick up, and a slight increase in power to maintain altitude, to compensate for the thrust that gets diverted to moving forward. Is that right? This part gives me the sense of being like a regular airplane in some ways, and if that's the case, it should be natural for me.

No, none of this will feel natural at all. It will feel wrong. First, the gimbal no longer vertically stabilizes. You set it at an angle, and it stays there. That angle is base on how fast you plan to be flying -- i.e. your forward pitch angle. A good place to start is 10-15deg. Set this before you take off.

The idea is you will be pitched forward that amount continuously. I.e. flying manual you are always moving. You rarely stop and hover, which is near impossible anyway with goggles on.

So there will be no gradual trip down to the end of the driveway, stop and turn around, and fly back at 5mph. It's gonna be hours and hours and hours of M practice before you're safe down in the trees.

5) Stop at the end of the driveway. Pitch returned to neutral, which it will do on it's own by letting go of the right stick, and decrease power slightly. Yes?

NO!!!! Can I yell this louder?

THAT is the big difference between rate mode, and angle mode. In angle mode -- the way you've been flying so far -- the pitch matches your stick. If the stick is centered, the pitch is level. Push this stick forward a little, it pitches forward a little, and stays there until you move the stick more or bring it back -- and the pitch angle follows the stick position.

Now, think about how the yaw stick works. Quite differently. The rotational position of the drone doesn't follow the yaw stick -- that would be really hard to fly. Rather, the yaw stick controls the rate at which the aircraft rotates -- push the stick farther, it rotates faster. Let go of the stick and the drone stays pointed where it is -- it doesn't rotate BACK to the orientation it was in when the stick was centered.

The yaw stick controls the RATE of yaw, not the compass angle of the aircraft.

This is how the pitch and roll operate in M mode. The control the RATE of change. So, when pushing the pitch stick forward, it will start to pitch over, faster if you push the stick farther. When you release the stick, it will stop pitching, and stay at that pitch angle. To get it back level, you have to pull the pitch stick back, and release when it's level.

This difference in control behavior is what's going to send you into a brick wall if you don't develop this "muscle memory" way up in the sky where there's nothing to hit.

6) At that point, turning around and coming back, then stopping, will just be a repeat of motions that I've already done, but they'll be in "reverse command" with the drone facing me.

For this entire process, I don't expect to exceed 2 -3 mph.

Did I get anything wrong in this sequence?

Thx!

Nope... You need an entirely new start-up plan... Take off and land in N, fly up 150' above the trees, switch to M. Get to know that BRAKE.

 

[Chaosrider]

I don't have the DJI FPV, but I've read plenty of reports of failed attempts to take off in Manual mode. Likely caused by the angle that the quad sits at while on the ground. I'd recommend taking off in Normal mode, then switching to Manual once airborne.

Others have made that recommendation as well. It's starting to look like the right choice.

But if I'm going to do that, I'll need to develop a checklist style sequence of what actions I'll perform, in what order. Assume for this purpose that my objective is to hover as best I can learn to do, while in Manual mode, until the battery starts to run dry, then land. I realize that this will be an "active" hover, very much like flying a taildragger, and even more so, like taxiing one. Which, at least, I've done.

So, under this scenario:

1) Take off in Normal mode and move to the practice area, and hover. Given the slope of the ground, moving 50 feet toward the creek from my forward driveway will accomplish this, even if I don't climb at all, which I will a bit.

2) Do thing-1 to get to Manual mode
3) Do thing-2 to get to Manual mode
4) Do thing-3 through thing-n to get to Manual mode

5) Be in Manual mode for a while

6) Switch back to Normal mode, and land

What are things 1-n?

Thx!

 

[EpicFlight]

Manipulating the throttle unsprung in N mode is gonna be weird, so do a bit of N flying with it like that. It's real easy to drift up or down while you think you have it centered.

Takeoff is similarly odd. After you've done a little flying in N mode with the throttle stick unsprung, you can carry on with M fun.

Head to practice location/although in N mode. Hover in place. Adjust the camera vertical angle to 15deg.

When you're ready, switch the mode switch to M, give a little forward roll stick until the horizon looks level, then let the stick recenter. you will now be flying forward.

You will also need to increase the throttle a bit at the same time.

Try some uncoordinated (yaw-only) turns. It will mess up your pitch and roll angles, and you'll have to correct.

Please don't do any of this live for the first time. You WILL crash, quite possibly catastrophically.

Don't worry about not being able to use the DJI sim... Just run one of the recommended ones on your PC, with the DJI controller plugged in. You need to retrain your brain first.

 

[Chaosrider]

Takeoff is similarly odd. After you've done a little flying in N mode with the throttle stick unsprung, you can carry on with M fun.

Head to practice location/although in N mode. Hover in place. Adjust the camera vertical angle to 15deg.

When you're ready, switch the mode switch to M, give a little forward roll stick until the horizon looks level, then let the stick recenter. you will now be flying forward.

You will also need to increase the throttle a bit at the same time.

Try some uncoordinated (yaw-only) turns. It will mess up your pitch and roll angles, and you'll have to correct.

Please don't do any of this live for the first time. You WILL crash, quite possibly catastrophically.

Don't worry about not being able to use the DJI sim... Just run one of the recommended ones on your PC, with the DJI controller plugged in. You need to retrain your brain first.

Somehow, this is becoming more fuzzy in my mind, rather than more clear...

Manipulating the throttle unsprung in N mode is gonna be weird, so do a bit of N flying with it like that. It's real easy to drift up or down while you think you have it centered.

Perhaps, but it seems like it would be very similar to the friction-locked throttle on a Cessna single, which would be entirely natural for me. Maybe it's my Instrument rating heritage, but I watch the flight data pretty closely while flying. If I'm going faster or slower than I expect, I think I'd notice that.

I read through the FPV manual again last night, and the information it provides of Manual mode is almost indescribably lame. Skimpy, and vague.

But it occurred to me that if I also stiffened the right stick, it should be possible for me to set it to hover in zero wind conditions. At a fixed altitude, attitude, and power setting, it should remain stationary with no wind.

Right?

In a strange turn of events, I'm going to be blessed with almost zero wind all morning, and into the early afternoon.

An OP somewhere said that the right place to put the sticks to hover shows up in the goggles when you go to Manual mode. Is that right? If it is, I should be able to take off in Normal mode, hover, convert to Manual mode, set the sticks as indicated in the goggles, and it should then continue to hover, in zero wind.

Yes?

When you're ready, switch the mode switch to M, give a little forward roll stick until the horizon looks level, then let the stick recenter. you will now be flying forward.

It seems to me that there are a number of sub-steps to this. Apparently there's a proper sequence of events between moving the toggle switch on the controller to M, and setting M in the goggles, which itself involves a number of steps. Can you tell me what those steps are, with a bit more granularity?

Try some uncoordinated (yaw-only) turns. It will mess up your pitch and roll angles, and you'll have to correct.

My intention for my first flight is to simply hover...by active control if necessary...and then make small changes in throttle or attitude, and see what happens. I don't expect to "go" anywhere until this becomes natural.

Don't worry about not being able to use the DJI sim... Just run one of the recommended ones on your PC, with the DJI controller plugged in. You need to retrain your brain first.

Recommended...where? Plugged into the PC...how? With a USB cable from the goggles?

I confess that it strikes me as weird that nobody has written this up in some crisp, checklist format. Maybe that will be my contribution to FPVing...

Thanks for your help! I'm really not trying to be difficult about this.

 

[EpicFlight]

Recommended...where? Plugged into the PC...how? With a USB cable from the goggles?

FPV Simulators

 

[EpicFlight]

Perhaps, but it seems like it would be very similar to the friction-locked throttle on a Cessna single, which would be entirely natural for me. Maybe it's my Instrument rating heritage, but I watch the flight data pretty closely while flying. If I'm going faster or slower than I expect, I think I'd notice that.

My intention for my first flight is to simply hover...by active control if necessary...and then make small changes in throttle or attitude, and see what happens. I don't expect to "go" anywhere until this becomes natural.

You can fly in N mode with the throttle unsprung and easily find the zero (mid) point of the throttle, and hover in place. No control input after establishing the hover. However, keep in mind that in N mode the left stick is not actually the throttle, but a simple command input that says "ascend/descend" and how fast. It is not directly controlling the throttle.

So, you can leave the left stick untouched, move forward/back left/right with the right stick alone, and the drone will execute those movements while holding altitude perfectly.

What's hidden from you is all the rapid throttle variation the FC is executing to hold altitude, while your command inputs are changing the power split between lift, and horizontal thrust. Using all the sensor input it does an incredible job of this – far better than you can.

Switch to M, and now all that's up to you. Change the attitude of the aircraft, and the split between lift and thrust changes, and YOU need to manage those changes with the throttle to maintain altitude.

So, you follow your plan. You get to your hover, switch to M. Now, even on this windless day, the aircraft starts drifting (there is always air movement). You attempt to correct with right stick input. It start to descend, because you're robbing lift. You compensate with throttle, but wait, the horizontal correction is not stopping, oh yeah, rate mode! Oh yeah, I have to level it out, it doesn't do that on it's own.

Please trust me, as one who has made this same transition, you are overconfident in how easy it will be to hover, because you've been spoiled by all the automation in modern drones.

If you have a school or park nearby, go there in a big open space and try hovering in that environment. Do it without goggles, and close by (20-30 feet). That's the best way to learn hovering in M mode.

 

[okw]

While I haven't flown the DJI FPV, I do have FPV freestyle quads, and years of experience with RC helicopters, which handle very similarly. I can concur with the statements that hovering in Manual mode is going to be very difficult. In fact, it will possibly be the hardest thing you will try to do in Manual mode.

You will never find a spot with the sticks that allows it to hover in place. Even if indoors. It will always be drifting. This drifting is much harder to control using the goggles than it is when looking at the quad line-of-sight, because you won't notice the movement until it's already gone several feet. Not only are you going to have to constantly control the pitch and roll to hold it's horizontal position, you will also need to constantly control the altitude.

There are videos online with instruction for learning to fly an FPV (non-DJI) quad. In addition to watching some of these, you should also find some way to get some time on a simulator. I'm partial to Velocidrone on a PC. But I don't have a DJI controller, so not sure how you would go about hooking one of those up.

And I would suggest leaving the hovering for Normal or Sport modes.

 

[Chaosrider]

FPV Simulators

Too late...on my second flight, I put it in a tree.

Which might be OK...I already have an expert drone-from-tree rescuer...but I can't quite determine which one.

I hit the "Find My Drone" and it replayed the last 30 seconds of flight, so I know generally where it is, but not with certainty. I drone to where it was...pretty close...but I couldn't see it.

So I went on a recon with one of my Mini-2s, and couldn't see it. By then the sun was way too bright, and the wind was picking up, so I couldn't get as close to the trees as I wanted.

I'll give it another shot tomorrow morning.

(sigh)

TCS

 

[EpicFlight]

Oh, I am so sorry!

Let's hope you find it easily, and the worst is a bent prop. It's pretty tough, and I'm guessing you weren't going too fast.

Did the same thing with my first drone, a Phantom 3. I was a virgin noob back then

 

[Chaosrider]

Oh, I am so sorry!

Let's hope you find it easily, and the worst is a bent prop. It's pretty tough, and I'm guessing you weren't going too fast.

Did the same thing with my first drone, a Phantom 3. I was a virgin noob back then

Found, bent prop replaced, and he's back in the air!

Aside from the prop, the only real damage was the punctured battery. The battery was ejected during the crash.

Definitely a tough little bird!