Install a electri generator on rotor head

[autogyro]

I have a idea, does it work?

Install a electri generator on rotor head, in cruise flight status, it can generate electry power.

My question is: this generator will generate friction, the friction is greater than the energy they generate electricity?

Regards
Edward

[karlbamforth]

No free lunch I'm afraid Edward.

Essentially its the engine that drives the blades albeit indirectly.
You may as well put the generator on the engine it would be more efficient.

Of course with your idea if the engine stops you will still be generating electricity but would you need it, do you need the complexity ?

[jcarleto]

If you want a non-engine connected generator, go with the old standby bicycle generator with a little propeller on it. They have been used on all sorts of ultralight aircraft for years. It's still no free lunch. You trade a tiny bit of extra drag for power.

[PW_Plack]

It would be a little like using an alternator on the wheel of a car. The only big advantage would be the ability to power avionics or a landing light to allow safe landing in the event of a failure of the engine-driven system.

There would be some friction loss in the belt or gear used to drive the alternator from the rotorhead, but the load on the rotor would be minimal until you actually put an electrical load on the alternator. Most machines will still fly if you accidentally leave the rotor brake on, so there's no reason it couldn't be done.

But it won't be efficient.

[lawn dart]

I've kicked around the same idea but shy ed away from using the rotor for fear of creating drag and couldn't see enough rpm to run the generator up to speed, trying to figure out electric start and charging system for my Mac with out adding a ton of weight, also will be trying out a electric prerotator shortly.

[autogyro]

Thanks all above responses, I would consider those carefully.
Regards
Edward

[BobK]

This could be more of an idea I have thought about if we gather the by product of autorotatonal flight, giration. The energy of lead/lag will have a more predictable energy pattern to 1st tickle a set of coils with an output from a DSP based on a waveform sensed with another set of coils. The vibration of giration can then get the driver coils to charge an flyback on the output coils. AC power for autogyros is what will beat DC and any PCM (power control module) and harmonic reasonance of rotation will be the source of this power. Of any method this has the least drag, but could reduce noise related vibrations as well (coils sets on blades). This would require a little more of a lab than I have now, but I've tested very similar electronic circuits. If you want to build it I'll help, but I need a favor someday and what ever it is... ;)

[PW_Plack]

...The energy of lead/lag will have a more predictable energy pattern to 1st tickle a set of coils with an output from a DSP based on a waveform sensed with another set of coils. The vibration of giration can then get the driver coils to charge an flyback on the output coils. AC power for autogyros is what will beat DC and any PCM (power control module) and harmonic reasonance of rotation will be the source of this power...

Bob, I can't claim to have followed you there, but in a two-bladed, teetering gyroplane rotor, the blades are always 180º opposite each other. They lead/lag in unison, with no relative change in position between the two blades, or in either blade's radial relationship to the rest of the rotorhead.

You could harness the teetering (flapping) motion itself, but introducing resistance into the flapping, inhibiting the process by which lift is equalized between the sides, may increase vibration and stresses on the hardware.

Resonance doesn't produce any power. It can only store power. A resonant system's oscillation decays as soon as the input pulses are removed. Any power derived from the motions of the rotorhead originated in the aircraft's powerplant, however indirectly coupled.

[Resasi]

The gentleman who produces the German Skydancer has a prerotator that then doubles up as a generator.

[brett s]

Tanstaafl...

[BobK]

Paul I didn't think of this hub, but the original Alpha hinge hub and more than 4 blades. And while you are very right about reasonance doesn't make the power it does allow you to tune it to the load. The flyback of the vibration to the coil sets with pre charge from tickler coils is where the power from by product and quieter operation. There is no free lunch and I'm only cooking a little snack for the imagination that all. This investigatoin as to how much energy from vibration can be used or loaded at a tuned frequency (or ramp of frequencies for later power tunning to the load) that will not stall or slow rotational speed isn't going to be cheap. It could be simulated first, but not with any software I currently have. If it were modeled as small scale in a little wind tunnel coil & electronics size & weight greatly out weigh any returns of total energy. A maglev rotor hub? Six soft inflateable parafoil blades? If this loads vibration and lowers noise why can't it be investigated further?

[PW_Plack]

Bob,

There is some very interesting work going on right now by the helicopter companies, especially Sikorsky and AgustaWestland, using piezoelectric actuators to continuously reshape airfoils to optimize for drag or noise to meet needs of the moment. They envision optimizing for efficiency in cruise, then going into a low-noise "stealth" mode for military helos while landing in hostile territory, or for civilian medevacs landing at hospitals near residential areas, etc.

It's a little different with gyroplanes. The rotors make a gentle, hushed, swishing sound that most people really like. Take a listen to YouTube - Gyro Glider Boom Trainer Details Video.wmv (http://www.youtube.com/watch?v=U3zEqsvY7nA&feature=email) for an example. We'd be sad if that sound went away!

[autogyro]

Bob,
you said right, we should do experiments to verify my and your idea.
Edward

[Rotor Rooter]

This could be more of an idea I have thought about if we gather the by product of autorotatonal flight, giration. The energy of lead/lag will have a more predictable energy ....... The vibration of giration can then get the driver coils to charge ....

Is this new patent yours? ;)

US Patent 7,795,763, September 14, 2010
Electromagnetic device for converting mechanical vibrational energy into electrical energy.

[BobK]

not exactly since their idea bases upon two magnets and a coil. ...An electromagnetic generator comprising two magnets and a coil disposed therebetween, the two magnets being configured to define therebetween a region of magnetic flux in which the coil is disposed whereby relative movement between the coil and the magnets generates an electrical current ... My idea is all coils no magnets and a DSP. Will their patent get anything built any guicker? Will they get paid money once someone actually puts a shaking coil between two magnets? I have thought of writing patents about the dual arch configuration of airfoil and airframe for BiRotor, but that will never get one built. One proof of concept under 100 pounds air cycle is where my electronics have been designed to work together. That along with an ultralight intranet packeted information air traffic monitor on some alternate VHF frequency for thousands of these in close airspace. Sorry this idea isn't a real job,who'd hire a Flugtagist?

[BobK]

does anyone remember the regenitive receiver? the tickler coil takes the circuit to huge amplification (right before total oscillation) and allows a small signal to be detected. Now add two more sets of high Q transformers (hiZ input, low frequency response) at the null between vibration frequency limits. DSP those inputs to where the flyback coil is switch loaded. and did I get a little off thread on the last??? sorry