Ornithopter Photo's & Drawings #2
 

Rather than post the same pictures again, here is a link to the original thread (some very nice aircraft are posted there).
http://www.rcgroups.com/forums/showthread.php?t=324577

Here's a 1889 aircraft patented by R.J. Spalding. Pic inset 2 shows the contraption being supported by a balloon, so the designer must of intended the articulated wings as a method of propulsion and maneuvering only' (for his Flying Machine). If you were to build an articulated, feathered wing today, it would look similar to this design,,, hat's off to Mr. Spalding.
(I didn't bother to read the patent pages on this one but you can). http://patft.uspto.gov/netacgi/nph-P...&RS=PN/398,984

Pic 3, Here's a great shot of a bird flying and articulated wings in action. As you can see, thou not so obvious, the port side wings' area is slightly reduced in the photo. Almost certainly the bird has incountered a port side wind and has adjusted his wings for course correction.

The inventor of this 1877 ornithopter design, Murrel, claimed that his contraption actually flew.
Picture 1-2 shows what's left of his 'washboard wing' concept. A flapper valve type wing set-up, where the valves open on upstroke and close on down stroke, to where some kind of lifting bias would be achieved.
Pic 3, is part of his now well known patent of the ornithopter.

In reality, although this aircraft never flew, Murrel had the fortitude to go on and build his dream and should be considered a stepping stone toward ornithopter flight.

http://www.kids-online.net/learn/murrell/murrell.html

I recently encountered a computer problem where most of my ornithopter website data was destroyed. I have a few photo's for which I was able to save but who these people are, is a mystery.

Pic 1, a 1900 circa human-powered orni. Pic 2-3, a russian engineer and his wonderful models, the pictures were dated 1978 and 1980. The last one kind of reminds me of a giant airborne jelly fish,,, I wonder if it ever flew :)
Enjoy the pics. Willi

Mr. Mueller, I invite you to visit my website: aerosapiens.com. I feel that by the comments you have made that you can handle my invention in theory. It is 18 feet in span and about 5 feet in chord. Check out my site then get back to me about what you see. Especially, the subtle movements. I have viewed some 1800's patents too. I did not see the one you post. Very interesting. the man attempts to use his whole body to power the contraption. Thank you. Sincerely, David a Moore.

Wow, your the second birdman/towerjumper that's contacted me this month, I wish both of you all the best success with your flying machines.

David reviewing your website, it looks to me as your planning to build a flapping winged aircraft (fletcher) powered by a pilots arm movements.
My opinion is; it won't work. No matter what physical arm strength you can manage, it's still not enough. At best, you may be able to hold a 30 foot wing span out straight for a few seconds, but to flap as a bird or bat is out of the question.

Another problem I see, the design of your aircraft is wrong as well. Few people realize, a ornithopter's C of G is constantly moving around.
Pic 1, shows the CG of an ornithopter while the wings are near the wing-up' position is farther forward than when in a wing-down' position. As Pic 2-3 shows, the same applies to your aircraft. While your wings are in a dihedral postion, your CG is correct, your craft is flying level as intended. As the wings move into a anhedral postion (while flapping), your craft becomes tail heavy and will go unstable, causing you to fall out of the air.

Of course this is just my opinion and I could be wrong about it, but without a long tail to stabilize your aircraft, you need to keep flying over water until you have these things ironed out.
And last, I'm impressed with your teams efforts so far. Welcome to the forum and Good luck, Willi

http://www.aerosapiens.net/

Added info 6-28-05
I was fortunate enough to find this photo backing a CG shift as I see it. Based on tail position alone, would suggest these birds are compensating for a CG shift.

Hello

Recently I stumbled upon an interesting online catalog of 18th and 19th century aeronautical prints, known at the Tissandier Collection. Click here for the website, with the index being accessed at this spot. Apart from being available online, the Tissandier Collection has also been packaged up onto a CD-Rom, and is sold commercially under the title "Early History of Ballooning". A search on eBay should yield a few listings for it.

Though mostly about ballooning, the collection does contain a few prints of ornithopters and the like. Below are a couple of a snipped images from one such print, this one concerning two ornithopters designed by J J Bourcart in 1866. The whole print can be accessed by pointing your mouse here. It's quite an amazing print, I think.

Cheers,
Paul

Willi,
I am confused as to why the C of M should shift fore and aft as you show it. Is this to do with the powering pilot's leg movements?
Paul's pictures of Bourcart's biplane show the same kind of counter-rocking as Tupolov's machine. Are there other examples of this principle?

Murray.

Willi,
I reckon the Egret's apparent asymmetry may be simply because of the forshortening of the port wing due to anhedral and the view angle.
Egrets are very photogenic.. there is a similar photo on the cover of David Alexander's book "Nature's Flyers" , a fascinating read.
Murray.

Murray, the C of M will stay about the same, no matter what position the wings are in.

[ As long as your ornithopter (craft) is not flying, you can check the CM or CG of the craft because the terms roughly have the same meaning. However when the craft is flying, the term 'CG' should only' be used because the Flight Glide Path is influenced by wing position. The C of M is the static balance point of an ornithopter and the C of G is the balance point of an ornithopter to "fly" a level glide path, and thou the CM/CG of the craft (physical balance once set) does not move (this applies to 90 degree wing sweep orni's only), the lifting properties of the wing will change because of the varying wing position angles, causing a CG shift as argued. ]

This is my opinion and I apologize for the confusion.

P#8, Yes, at first glance I thought the same thing. Only after looking a bit closer, thou not so obvious, it appears the birds LE port wing tip is angled back about 5 degrees. Also I interpret the feathers as being closer together (port side) reducing the wing area, favoring a left turn into the crosswind.

Willi,
I had understood that the term "C of G" was simply an imprecise variant of the proper physical term "C of M". You imply some other meaning.. could you explain it?

I can see that thrust will create a pitching moment, nose-down or nose-up depending on the instantaneous dihedral or anhedral, but over a complete flapping cycle it will average out to about the same pitch moment as a fixed wing set at the mean dihedral. A bit of cyclic pitching won't bother either birds or onithopters.

I built a model similar to the Velocipede Arien (the one on top). It was able to hover. Has anyone experimented with wings like this, coming to a point at the root?

Here's an article dated 12-3-04, dealing with professor James Delaurier's bold attempts in designing a man-carrying ornithopter. Flight tests were to begin in april, a quick websearch revealed no follow-up stories on whether it flew or not. http://news.com.com/The+wings+on+thi...tml?tag=st.num
Pic1, shows a runway test of the 750 pound craft. Judging by wingtip deflection, the ornithopter is in downstroke mode. Pic2 I assume, is the current team in charge of flight and maintainance.

Pic3, is a tailess ornithopter based on sketches by Leonardo da Vinci. As for the same reasons outlined in post #5, this design would not fly either.

In the background same pic, is da Vinci's 1483 parachute design.

Hello Willi,
Pic 1 was taken when I was still the test pilot....that's me in the cockpit ! Pic 2 could be the current team or could have been taken anytime in the last 2 or 3 years. I only recognize 3 people ! Dr Delaurier [standing beside the cockpit] Bruce Fenton [Chief Field Engineer] in the cockpit and Jim Merrit [in the yellow shirt] who built the aft fuselage and also the new cockpit after the crash.
The www.ornithopter.info website was listing June 18 and 19 for tests but then that was changed to June 24 and 26. Last time I checked it was still listing those dates so I don't know whether they did any testing then or not.
Cheers,
Patricia

Hello Patricia,
Looking at post #12 pic1, was their ever any discussion on putting a flap/spoiler on the center wing section of the craft to reduce pilot heave?

I would think near TDC, the control surface could be deflected down as a flap (adding lift), near BDC, deflected up as a spoiler (reducing lift).
A control surface 12" wide by the center sections' width and the craft approaching 60 MPH, should be a very effective anti-heave device.

What do you think? Willi

Hello Willi,
No, there was never any discussion on modifying the centre-section in the way that you suggest but it seems like a good idea to me and well worth trying.
Cheers,
Patricia

Here's my latest collection of smaller ornithopters, the yellow/blk tandem wing and red winger were purchased from Nathan. The Fly is actually a hard-plastic-body- mobil which strobed out to a flap rate of 6hz. Despite the batten-less wing design, the mobil puts out a surprizing amount of thrust by means of wing sail bellowing,,, I wonder if putting a few battens' parallel with the wing spar would increase the thrust output?
Anyways, I'll try to get some flying pictures of the other ones as soon as the weather permits.

Nice pics Wmueller10, love the fly. My ornithopter is based on a combination of insect and hummingbird flight. But I can not show any pics of it as yet waiting on a patent. Here is something that is simular to what I am doing and has inspired me, hopefully it can do the same for someone else. This is a lego man with wings but no tail section if the lego man was about six feet tall the dimensions would be pretty close to my project.

Yes, some of these flapping winged toys are inspirational, hopefully someone will make a RC fly one day.

I have been following your piloted ornithopter thread and based on what you've told us so far. You will have a 6 foot high, 14' wingspan, 15hz, hovering ornithopter. May I ask exactly how your going to affix a V-tail on this craft?

Based on your wing plan form, scaled in at 6' by 2.5', This is what we have so far.

Non-related,,, I've noticed your acronym/initials' alternate between HP and HB, what is your first name please. Willi

Your numbers are correct Willi, but hovering is my ulimate goal, flight first. My wing area and span will remain the same but my wing design is ever changing. The whole system is like a strap on spine the V- tail will extend about three feet past the heal. I would have to post a drawing tomorrow to show the correct placement. The tail section is actually the easy part of the project the best wing design is what is slowing me. It took me only 2 1/2 months to invent and build a drive system for the wings.
Yes I usually sign off with the H.P. which means Hummingbird Project the H.B. was a typo.
Later, Ronn is my first name.

Sorry I could not give a more detailed drawing, but you can get an idea of what I am trying to do. The strap on spine will consist of the wings, V-tail and drive system. If I can keep my wing weight down to 5lbs or under each the spine should be about 35 - 45 lbs max.

H.P

Thanks to the input and comments given to me by people who are on top of their game like Willi, Patricia, and Scott. I was able to go back to the lab and test a few things, crunch a few numbers, and improve some designs. So this is where I am at, the weight of my orni remains pretty close to my original calculations but my flapping rate has decreased a bit to 6 - 15 beats per sec. I'm also using a stiff wing design with a slight pitch movments on the down and up strokes. Hey Willi you where right about the tail position but I am still going to stick with V-tail out back cause it looks cool. Everything in the drawing is to scale the wing is 2 inches shorter than the final design though.

Ronn, good luck with your design. Willi

Check this out guys, Denis V. Curry has a very nice human powered prototype and he has achieve forward motion from rest with it. http://ovirc.free.fr

Also take a look at what my become the next robot on Mars. Dr. Robert Michelson and his team have made a chemical based ornithopter that gets 10 Hz now and will be able to do 60 hz later. I was able to achieve more than 30 Hz with an electric ornithoper so far but I do not need that kind of Hz with my project. But it is good to see that 60 Hz can be achieved just in case. Enjoy !
http://avdil.gtri.gatech.edu/RCM/RCM...erProject.html

Before anyone goes to the trouble of building wings on the lines of Denis Curry's design, I suggest constructing a "rings" gymnastic apparatus. Set a target for flight duration then try to support ones weight on arms outstretched for that length of time.
Sorry to be a wet blanket but I remain unimpressed by the flapping arm approach.
Murray

Does anyone know if he has done any experimenting recently. I noticed that his device first self-propelled itself in the 1970's. Also noticed that he bends his legs to move the wings through the upstroke then both straigtens his legs and pulls with his arms on rods/cables ? attached to the wings to flap the wings down. [he must have been in good physical condition !!]

Well Patricia I do not know if he did anything lately, but a year or so ago I did ask him if he could build me a pair of wings. But he could not at the time cause he was busy with his own rig. At that time I too was trying to build a human powered orni, but after testing I decided to use an electrical motor instead. Longer lasting, more consistant and faster strokes but still easy on the environment.

Patricia has pointed out some wires I had missed. So I am relieved that Denis Curry didn't expect to take all the weight on his outstretched arms. If after takeoff he intended to rotate his body horizontal, hang glider style that, with the foot action, might have been OK for an augmented glide device, something on the lines of the wing-suit. Without a clean fairing and much greater span though he is never going to fly level.
Murray.

Hello Willi,
Yes, I posted the link to Denis Curry's website a while ago but it didn't trigger the conversation that it has this time around. I was disappointed then because it's an interesting design and worthy of discussion though I personally think that engine rather than human powered is the way to go.
Cheers,
Patricia

Personally what I think would be worthy of discussion, is the progress you've made on your Nightingale so far and on Sean Kinkades full-size ornithopter project (a few pictures on either would be grand).
With that being said, I see nothing special about Denis Curry's ornithopter.
Looking at the video, I'd say he'd need about 3 to 5 times more flap rate to get airborne. Also, he has no way to control his craft if he does get aloft, no tail, no way to shift his body weight because of the reciprocating ROG platform design,,, top heavy, he could topple over like a domino if his wheels stopped abruptly.
Anyways I'll agree with you, an engine powered ornithopter first and then we'll tackel the "BirdMan" approach at a later time.

How about designing a human-powered ornithopter and installing an engine on it? I always wondered why they did not put a motor in the human-powered 'Karura' ornithopter? This craft looks like it would just leap off the ground with an engine in it, Curious very curious indeed,,, Willi

I will discuss Nightingale when I start the testing. It'll be much more interesting then since each test will be telling us more about what works and what doesn't !

Re: Denis Curry's design.......I think he was just testing the general concept and flapping mech for thrust to start with then he probably planned to add a tail etc and redesign for an attempted lift-off. I wonder if he's done anything further in the last 25 years. Of course, a design that is a good thrust producer is a long way from being a good lift producer and may , in fact, never fly. [ some of my models are in this category :( ]

I think the 'Karura' ornithopter looks a bit too 'spindly' to carry an engine though I agree that a human-powered orni that is built with composites could be successful if it was changed to engine power.

Cheers,
Patricia

The only human-powered design I'd think would even have the slightest chance of working, would be a pedal-powered, X-wing configuration. Possibly have the foot pedals attached to a flywheel for a even flap cycle. And then try out this clap and peel wing technology the Mentor ornithopter used :)

In reality, my X-wing wouldn't work any better than Denis Curry's design but it be the way I'd go. Willi

Question for you Willi. Do you think that two pairs of wings (dragonfly) as opposed to one pair of wings (birds) would be more effective when it comes to human carrying ornithopters?
Thanks, H.P.

Ronn,
I think their is no future for 2 winged ornithopters. They are inherently dangerous. In addition to the pilot heave everyone is talking about, a engine stall out near TDC or BDC could result in a fatality,,, just my opinion.

Your 2 winged project is doomed as well, the design below would have a much better chance of working (if it would work at all). A 4 winged craft with a tripod landing base. The wing trust is well above the CG so gravity is stabilizing the craft, Along' with the aerodynamic controls.

Your flap amplitude would also be cut in half so you maintain the 15hz flap rate that you envision. Willi

That is a more proven design for hovering like the U of T project, but I would like level flight like a bird. The kind of hovering that I intend to do is more on the bases of softening and shortening my landings. Like how a bird hovers for that split second as it gets it's talons in position to land on a branch. Or just long enough to take a piece of bread out of your hand. I do not intend to maintain a constant hover like a helicopter. That would burn to much of my power, I look at the Hummingbird because it has mastered that part of flying efficiently. I would like to hover when needed only, the 15 Hz would be put in play for this purpose, but level flight would be around 5 Hz hopefully. Through testing I will find out what works and what does'nt. Another question Willi, with the wing area that I intend on using can you calculate the amount of wing load I would encounter. Make sure you break it down into laymens terms for me.

Thanks, H.P.

>>,,,can you calculate the amount of wing load I would encounter. Make sure you break it down into laymens terms for me,,,>>

You'll have to ask the engineers for the wing load calculations as for I'm just a innovated modeler, they'll need to know the total weight of your aircraft and wing area. As a modeler, I use use trail and error to achieve success, not math.

Below, is a final concept drawing of the proposed 4 winger. I would consider building a 4 foot version of it using a nitro powered motor. Flap angle would be increased to 80 degrees per wing. Willi

Ronn,
On second thought, I do not believe an exact wing load calculation is possible,,, too many variables to factor in for wing load calculations. Willi

The reason that I ask is because I was looking into getting this giant scale rc model builder to build me some wings. The wings that he builds can be made to what ever size I need and they can be modified for my purpose. And I know that they can be strong but are they strong enough is the question. I will have to find out the wing load on those wings and some other numbers to be sure.

H.P.

Like a bird,
In being pessimistic about your chances of hovering I suspect perhaps we have been talking about different things.Large birds, eg. pelicans, on landing doing a few quick strokes at very high angles of attack, generating a last grab of lift and lots of drag. Inefficiency is good in landing; not so good in taking off !

This is not quite hovering as they do still have forward speed. As they pitch head-up the stroke turns more horizontal giving the wing forward speed even on the last downstroke as their feet touch the ground or the water.

Birds that perch on branches or poles etc. have a more elegant procedure, zooming up from below the branch in a trajectory timed, like a human trapeze artist, to come to a stop at the exact time and place required to clamp their feet on the perch. I have often wondered if we could do this with aircraft, employing something like an aircraft carrier siiting atop a tall tower.

Murray