Headless Mode (decapitated flying)

[HiDesertHal]

Hello,
Do most of you use the headless mode, or do you prefer to keep your quad oriented to the same heading as when launched?

Thanks,
Hal

 

[ArmyVet]

Some would say I fly with my head u* m* a**. Does that count?
Haha

I have never tried headless mode on any of my 4 quads. I used to fly old RC planes, so I may be more of a purist and orientation was fairly easy.

In my humble opinion everyone's eventual goal would be to fly like the Wright Brothers intended.

Good luck anyway you can yank and bank

 

[Gyro Doctor]

... I don't use it, but I can see how it would come in handy for a newb who's lost orientation and is already at the fringe of reception.
In a panic recovery situation it could mean the difference between having it come back to you versus flying away because it was
given the wrong directions and so obligingly flew out of range never to be seen again.

 

[Chuck]

I haven't tried headless mode yet. Having been on a multi-engine fixed wing aircraft crew, that doesn't seem normal to me.

 

[LoneRCRanger]

None of my quads have headless mode. They barely have Get Off The Ground Mode and See the Pretty Tree Mode.

 

[Tentoes]

Every time I've tried headless mode, I've crashed into something.

 

[SNSTRLefty]

My first quad, a Sharper Image stunt drone, had headless mode. I didn't mind it because I didn't have to be concerned if the trim was off and it turned on its own or if it bumped something and spun.

It would be nice to have that setting optional with my CX-30 when it gets far enough out I have trouble determining orientation.

 

[ArmyVet]

It would be nice to have that setting optional with my CX-30 when it gets far enough out I have trouble determining orientation.

Not sure about other quads. On all of mine you need to set "headless" mode on when you can see the quads orientation to yourself.

If you set it when you can't see which way it is pointed, then the quad probably will fly in any direction besides the one you want. I thunk

Maybe someone else can verify or explain this better.

Have fun.
With head or headless hehe
Bill

 

[LoneRCRanger]

As I have been told by other experienced quad pilots, when in 'headless mode" the quad will fly in the direction you indicate from the control stick, regardless of its orientation in the air in flight. Pulling the control stick back towards you the quad would fly back towards the transmitter regardless of your orientation on the ground. How it does that without GPS coordinates is beyond my understanding.

 

[Gyro Doctor]

Maybe someone else can verify or explain this better.

You are correct

How it does that without GPS coordinates is beyond my understanding.

You let the quad know it's orientation relative to you before taking off.

 

[LoneRCRanger]

You are correct

I'm correct, or is someone else correct?

You are correct


You let the quad know it's orientation relative to you before taking off.

And, how does that work then for quads that have headless mode but do not have GPS settings ability?

 

[Gyro Doctor]

And, how does that work then for quads that have headless mode but do not have GPS settings ability?

It's a control flow stack the MCU in the FC does the math for to interpret what command to give the ESC in order to achieve the desired result.
The quad is sitting in front of you facing away from you when you tell it to set it's orientation, this we will call zero degrees. The quad now knows
that where ever it flies away from you it has to find 180 degrees to get back to you.

Let's begin:
The quad flies straight away from you, then you make a perfect right turn. The chip notes a 90 degree turn and retains +90 in memory.
You make a 50 degree left turn. The quad subtracts that leaving +40 in the memory. You now turn left again 80 degrees.
The quad's memory is now at -40. The quad flies out of sight and you hit RTH. The quad knows it's at -40 relative to it's zero setpoint,
and so adds a -140 control input to derive the 180 value, thereby sending it back from whence it came.

It chooses the lesser of any value needed to add to it's current memory in order to achieve the 180 value, be it negative or positive.
For example, if it's last heading was +90 from zero it would add +90 to get home (instead of -270). If it was still flying directly away
from you it would have to add 180 to zero to come back.

 

[ArmyVet]

It's a control flow stack the MCU in the FC does the math for to interpret what command to give the ESC in order to achieve the desired result.
The quad is sitting in front of you facing away from you when you tell it to set it's orientation, this we will call zero degrees. The quad now knows
that where ever it flies away from you it has to find 180 degrees to get back to you.

Let's begin:
The quad flies straight away from you, then you make a perfect right turn. The chip notes a 90 degree turn and retains +90 in memory.
You make a 50 degree left turn. The quad subtracts that leaving +40 in the memory. You now turn left again 80 degrees.
The quad's memory is now at -40. The quad flies out of sight and you hit RTH. The quad knows it's at -40 relative to it's zero setpoint,
and so adds a -140 control input to derive the 180 value, thereby sending it back from whence it came.

It chooses the lesser of any value needed to add to it's current memory in order to achieve the 180 value, be it negative or positive.
For example, if it's last heading was +90 from zero it would add +90 to get home (instead of -270). If it was still flying directly away
from you it would have to add 180 to zero to come back.

So any quad that has "headless mode" capability has a compass at minimum?

 

[Gyro Doctor]

So any quad that has "headless mode" capability has a compass at minimum?

No, it's just doing simple math ... when you set the zero reference it adds whatever degrees of input is needed to total 180 so it knows
it's heading back to where it started from. I'm just using compass nomenclature for ease of explanation.

 

[LoneRCRanger]

OK, so for headless mode to work, the quad must be sitting in front of you when you set headless mode on. It can't be airborne and then have headless mode turned on because it won't have an initial reference point to calculate direction. Is that the gist of it?

 

[Gyro Doctor]

Exactly ... You can turn headless mode off and on at any time of course, but you need to set it's initial reference before there's any useful RTH functionality to be had from it.

 

[LoneRCRanger]

I am relieved, if I ever have a quad with headless mode, I shall know what to do. At this time my two quads have a mind of their own, especially when Trees and Tall Bushes surround them. This would be called "Mindless Mode"!

 

[ArmyVet]

No, it's just doing simple math ... when you set the zero reference it adds whatever degrees of input is needed to total 180 so it knows
it's heading back to where it started from. I'm just using compass nomenclature for ease of explanation.

Okay..........But I am still cornfused. What is it using to measure 90 degrees or 180 degrees?? What is its reference to start with? Without a compass or a gyro (pun intended....) on board?

 

[Gyro Doctor]

This would be called "Mindless Mode"!

... LMAO ... Yep, without obstacle avoidance thrown into the mix RTH will likely have you flying into something.
But I suppose even that is better than just flying off into the distance never to be seen again .... been there ... done that

 

[Gyro Doctor]

Okay..........But I am still cornfused. What is it using to measure 90 degrees or 180 degrees?? What is its reference to start with? Without a compass or a gyro (pun intended....) on board?

I honestly don't know exactly how the MCU considers the inputs relative to any azimuth (a misuse of the term azimuth, since
there's no real relationship to any headings in the strict sense of the term) but my best guess would be that when you're "setting
the reference point" it zeroes the stack and then it likely considers how many pulses are sent for driving in whatever given direction.
By tracking the sum of whatever it's counting then using simple math it then knows how much of that same input to apply to equal it's
intended RTH direction. There needn't be any relationship to compass or gyroscopic directions at all other than it's simply keeping a
running total so it knows how much to add to that in order to send it back. My use of "degrees" for rotation was only for ease of explaining
how the effect works.

It IS because there's no compass or inertial navigation guidance (gyroscope) referencing that most RTH functions are crude "ballpark only"
functions. They don't compensate for drifting or wind so, while it's better than nothing, the best they do is at least send the quad back in
the general direction it came from. The ones that DO employ compass, gyro, or GPS correction are much more accurate of course, but
the "toys" just don't do that.