Ban all helicopters.

[3WE]

No wonder you can’t steer them away from airliners.

https://www.facebook.com/share/r/1M8tTU ... tid=wwXIfr

[Not_Karl]

No wonder you can’t steer them away from airliners.

https://www.facebook.com/share/r/1M8tTU ... tid=wwXIfr

What could possibly go wrong?

[elaw]

My company actually came up with a different way of doing all that: https://patentimages.storage.googleapis ... 508439.pdf

[Gabriel]

My company actually came up with a different way of doing all that: https://patentimages.storage.googleapis ... 508439.pdf

It's not clear from the patent (actually it's not there, clear or not) how you would do to control the flap actuation cyclically changing it's deflection at specific angles of rotor rotation, collectively for all blades in every position, and both combined, or how the control inputs get from a fixed point (cockpit) to a flap in a rotating blade.

[elaw]

Oh yeah, to create a complete control system for a helo requires a lot more stuff... electronics, a means to get the power + signal from the non-rotating to the rotating bit of the helo, etc.

Such a system was never designed or tested, but a simple setup with a set of blades hooked to an engine was built and spin-tested to verify that the "heliflap" could be used to vary the lift produced by the blades.

[Gabriel]

Oh yeah, to create a complete control system for a helo requires a lot more stuff... electronics, a means to get the power + signal from the non-rotating to the rotating bit of the helo, etc.

Such a system was never designed or tested, but a simple setup with a set of blades hooked to an engine was built and spin-tested to verify that the "heliflap" could be used to vary the lift produced by the blades.

Again, maybe I missed it in the patent because it is long and written in "patent" language which is an obscure variation of English.
It is very very very easy to move a control surface (be it a flap or moving the whole airfoil). Planes have many control surfaces and nowhere close to the complexity of the control system of a helicopter. because what makes it complicated in the helicopter is that the airfoil or flap that you want to control is spinning, so you need to transmit the signal and the power (be them mechanical or electrical) from a non-rotation frame to a fixed frame. Nature is famous for having problems with that that's why there are no wheeled animals. (nature could not work around transmitting nutrients, muscle power and nervous signals from the main body to a spiny thingies).

That's already a complication that needs to be solved. The fact that the angle needs to change at each point of the circumference makes it even more complicated.

[elaw]

Yeah, it was done with a grant and the scope of work was only "see if you can stuff a motor into the blade with a flap and deflect the blade" so that's where it ended.

But it's not hard to picture with a microcontroller(s) and some power electronics, making the electroflapotronic device do the right thing at the right time wouldn't be that hard. Not a whole lot different from port fuel injection, except that instead of scheduling a pulse, you're scheduling analog values.

[Gabriel]

Yeah, it was done with a grant and the scope of work was only "see if you can stuff a motor into the blade with a flap and deflect the blade" so that's where it ended.

But it's not hard to picture with a microcontroller(s) and some power electronics, making the electroflapotronic device do the right thing at the right time wouldn't be that hard. Not a whole lot different from port fuel injection, except that instead of scheduling a pulse, you're scheduling analog values.

I don't understand the port fuel injection analogy, but I think that I am not making my question clear...

You have a flap in a helicopter blade. That flap has an electromechanical actuator. The whole thing (flap, blade, electromechanical actuator) is mounted on a shaft that spins, and that shaft is supported say by a bushing or bearings, it doesn't matter, but the bushing or the outer ring of the bearing does not spin. The source of power and signal for the actuator has to be mounted on the bushing side, that is, the non-spinning part.

How does power and signal get to the actuator? You cannot use cables or they will get all immediately twisted.
Brushes? Doesn't seem too reliable or maintenance-friendly.
Contactless induction may be workable? (I don't remember enough of electricity and electronics)

As an example, TPMS (tire pressure monitoring sensors) placed in car wheels get away with it by being wireless, but...
1- They require minimum power (they are just sensing pressure, not need to do "work" except transmit a very faint wireless signal).
2- They are battery-operated so you have to replace the battery every once and then (actually you replace the whole sensor, battery included).
3- But due to 1 the battery lasts very long, normally longer than the tire itself, so you can replace both together.
4- They are not critical at all, the car will continue to operate safely forever with a non-functional TMPS (or all 4).

(2 and 3, newer TPMS are even passive, like the toll tags, being excited/powered by the same signal radio that interrogates them, but good luck with powering any actuator with that)

[elaw]

Oh I get ya... and yes, there are definitely some practical problems that would have to be solved to make this work.

If it were me and ignoring redundancy, I'd probably do something like this:

• Most of the electronics, including the computing device(s) would be mounted on the mast and thus rotating (to minimize # of connections to the airframe)
• Power would be supplied through slip rings. Probably with a battery backup in the rotating assembly in case of contact failure.
• Communication between the rotating electronics and airframe would be through a rotary transformer. I have a design in my head that I have a hard time describing... picture a donut, but squared off (so the overall shape is still a circle but the cross-section is square), Slice it horizontally through the middle. Wind some wire on each of the resultant halves, then mount one half on the bottom of the mast and the other half to the airframe, such that the two halves are coaxial and very close together. The whole device with the two windings would constitute a transformer through which data could be transmitted, with one half rotating and the other half not. I've seen video recorders that couple the signals from the rotating heads to the chassis this way.
  
  A variation on the above which could be easier as it's tough to transmit data fast and bidirectionally through a transformer, would be to use the transformer to send data to the rotating electronics, and an optical link (LED on the bottom of the mast shining onto a photodiode that's fixed) to send data from the rotating electronics back to the airframe.

[Gabriel]

Oh I get ya... and yes, there are definitely some practical problems that would have to be solved to make this work.

If it were me and ignoring redundancy, I'd probably do something like this:

• Most of the electronics, including the computing device(s) would be mounted on the mast and thus rotating (to minimize # of connections to the airframe)
• Power would be supplied through slip rings. Probably with a battery backup in the rotating assembly in case of contact failure.
• Communication between the rotating electronics and airframe would be through a rotary transformer. I have a design in my head that I have a hard time describing... picture a donut, but squared off (so the overall shape is still a circle but the cross-section is square), Slice it horizontally through the middle. Wind some wire on each of the resultant halves, then mount one half on the bottom of the mast and the other half to the airframe, such that the two halves are coaxial and very close together. The whole device with the two windings would constitute a transformer through which data could be transmitted, with one half rotating and the other half not. I've seen video recorders that couple the signals from the rotating heads to the chassis this way.
  
  A variation on the above which could be easier as it's tough to transmit data fast and bidirectionally through a transformer, would be to use the transformer to send data to the rotating electronics, and an optical link (LED on the bottom of the mast shining onto a photodiode that's fixed) to send data from the rotating electronics back to the airframe.

Good ideas. I suppose that if you can transmit power effectively, signals can be transmitted wirelessly both ways.

In any event, the main idea I wanted to convey in my first response was that all the complexity that you see in the cyclic and collective mechanism is not due to having to make the blades change the pitch, but do to having to transmit power and signal from a "fixed" point to tell the blades that are on a rotating shaft to change pitch all at once and individually at the same time. You can still put a servomotor to change the pitch of the whole blade and transmit power and signal in the same way (whatever that way is) than for your electromechanical flap actuator, and the complexity would be similar i both approaches. Or, you could also have a complex purely mechanical mechanism to move just the flaps and the complexity would be similar to what we see in the video.

[3WE]

Everything breaks.

[3WE]

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¿Qué podría squidalir mal?