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David Hickman
David Hickman • Oct 19, 2011

Mechanical Morphing Helicopter Airframe/ Rotor Disc Control

Independent inventor; mechanically inclined; worked on cars and obsessed with mechanical problem solving. Had an idea 15 years ago, but it was put on the back burner due to life. I have a little back ground in precession machining. During my first deployment to Iraq, started reading books on aerodynamics brought the idea off the "burner". Spent the last 6 to 7 years tweaking this design
. It is a mechanical morphing airframe or in-flight reconfiguring airframe with a "human interface" concept to assist in mechanical control. The HIR airframe uses "human interface" along with an offset axis gimbal joint to "morph" the airframe thereby tilting the rotor disc for directional control. This slightly manipulates the center of gravity. Charles Seibel was first to design a helicopter with human interface control. The GEN H4 uses a gimbal, yet it is a fixed pitch coaxial design. You can track it progress at: https://envisionrotorsystems.blogspot.com/
Or at You Tube: "davh72able"
I am receptive to all comments. As always when I finish the small scale RC prototype, if it crashes I will still post the video. It’s already crashed once...weight distor was off a bit and the airframe developed a torsion flex. You can read the comments of pilots and aero-engineers if you go to most helicopter forums and search for "Morphing airframe" or "In-flight reconfiguring airframe" or my user name "davh12". Good to read in all of your topics. It is very interesting. I am not a certified engineer, just an "uncertified basement engineer". I do not let that title hinder what I do....in fact I think garage and basement tinkerers have an environment better suited not just think outside the box, but apply themselves in the same manner as well. An inventor must be willing to ask themselves "where does practical application end and novelty begin? Then answer that question honestly. How will your idea affect the market? Will the change be positive and how will it benefit everyone? I presented my design to DARPA and now Bell Helicopter is taking a look...no promises though. DARPA process and results are posted on my site.

Regards,
Dave
David Hickman
David Hickman • Oct 19, 2011
I have received some positive feedback from engineers and pilots. One patent pending for it. Bell Helicopters is taking a look at it, but it's been a year so quess they're not interested. DARPA took a look as well as a few others. DARPA siad that it had merit, but they felt that the payoff was not high enough for DOD.
Human Interface Rotor System helicopter (HIR) US Patent App. # 12,462,595
The HIR airframe uses "human interface" in conjunction with an offset axis gimbal joint to "morph" the airframe thereby tilting the rotor disc for directional control. This slightly "flexes" the center of gravity. Charles Seibel was first to design a helicopter with human interface control. The GEN H4 uses a gimbal, yet it is a fixed pitch coaxial design. The HIR system does not have any linear shift in weight / CG.
The Human Interface Rotor System is only a motion and balance physical-interface system in its current configuration. The weight of the pilot is in balance with the rest of the upper airframe aft and distributed between the two airframes. The goal is to combine haptic and physical interface with a computer system that assists with pilot control. The HIR rotor system can then become a platform with an intelligent control system. Our Japanese counter parts are already working with HMI and HAM, but I have not seen it applied to rotorcraft as of yet. I have a few other things not related to rotorcraft that I'm working on....a chasis for an electric car, etc.
A few earlier vid clips:

https://www.youtube.com/watch?v=jFE4P8cE1qk

https://www.youtube.com/watch?v=NDuv6SNJByM

https://www.youtube.com/watch?v=B2cwvvqHckY

Dave
David Hickman
David Hickman • Oct 23, 2011
I made significant changes to the airframe to lower the center of gravity. Both electric motors are still good. Still trying to track down a suitable mixer/speed controller. When I first started this prototype, I did not take into account the servo spacing. My patent drawing are for a manned platform. The servo pushes the upper airframe about 1 inch higher than it should be, displacing the weight and CG in a vertical manner. There is also a good chance that this is also what caused the torsion flex in the airframe and failure during the first tethered flight.
Regards,
Dave

[video=youtube;RBakcigwLAA]https://www.youtube.com/watch?v=RBakcigwLAA[/video]
David Hickman
David Hickman • Oct 27, 2011
Keep in mind when you see the completed demonstrator prototype, the rotor hub is not part of the patent. The "rotor system" I have integrated into the airframe, eliminating the swash plate. You'll see a typical RC heli rotor hub, but the directional control is attained via the mechanical morphing airframe itself. It was just easier to utilize an RC rotor hub for small scale. Any hub , semi-rigid, fully articulated etc will work with this airframe. Semi-rigid will only work on a full scale man carrying platform, as flapping/teetering rotor hubs ar not used in RC scale fixed pitch with regard to typical 90 degree and delta 3 45 degree teetering hubs.

Dave
impressive work.
David Hickman
David Hickman • Nov 7, 2011
Jigarmech,

Thanks. I should have the parts that I need by the end of the week to correct the electrical issues. I'm trying to balance this project with a chair that I'm making for my wife. I do a little wood working as well. When I get frustrated with one project, I change to the other so that I do not lose focus or allow my thought process to become clouded by anger. That and I must wait until I have the money for the parts.

Regards,
Dave
David Hickman
David Hickman • Nov 21, 2011
I've been working with a frenzy trying to finish my wife's chair and end table along with my project. Got everything loosely put together yesterday and something on the bottom of the motor burnt out, but the motor still works. Some type of circular chip board on the base. Anyway, with the rotor hub loosely tweaked and no servo attachment, with 1/4 bat charge, the helo was lit on it's frame and stable. That surprised me because without the servo attached, the airframes can move forward and aft freely. Hope to have it going this week. Still need to tweak the hub assembly to tightend down the swash plate input control rods which serve no purpose now without the swash,
Dave

[video=youtube;qsWxolFoZ2Y]https://www.youtube.com/watch?v=qsWxolFoZ2Y[/video]

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