My own personal airship

[Vorpal Bandersnatch]

My dreams of lighter than air flight have finally come true - although perhaps not quite on the scale I'd like. At any rate, it is till a ton of fun! I've got it setup to be controlled wirelessly through a Wiimote. It's also capable of autonomous behavior, but it is surprisingly difficult to get it to operate consistently - a blimp has extremely low friction so a small action by the motors can have a big impact. Eventually I'd like to get/make a better envelope in a different color scheme and make the whole thing properly steampunk. Also, a wireless video feed and an array of better sensors (altimeter and compass particularly, and a full blown Inertial Management Unit if I'm greedy...) would open up the possibilities for autonomous behavior immensely. Any hints about working with Mylar or finding suppliers would be greatly appreciated.

Without further ado, here she be:

Spoiler (click to show/hide)

[Pike]

This is very creative.  And you control it with a Wiimote, you said?  That's... fantastic.    I love stuff like that.  You wouldn't happen to have a video of it in action, would you?

[Zurael]

Excellent. I am especially impressed with the wireless control. I am wondering, what powers the onboard motors? A small battery pack?

As for control issues, if you reduce the moment arm distance between the propellers and the center of gravity, the degree of thrust synchronicity wont need to be as exact to fly straight. Also the addition of fins or a rudder may help with stability.

Inertial sensors... Ive seen chip mounted solid state accelerometers for sale not too expensively, I'm sure it wouldn't be too hard to have them transmit information to a receiver of some kind.

Looking forward to seeing it develop.

[Vorpal Bandersnatch]

Here's a short video of the wiimote controlling things - the accelerometer readout from the Wiimote controls the tilt of the fans, and the D-pad controls whether they blow forward, backwards, or in opposing directions to turn.

Spoiler (click to show/hide)

http://www.youtube.com/watch?v=aSfX9a9feWs

[Captain Quinlin Hopkins]

The cheapest source of Mylar you'll find in small quantities will be the "emergency blankets" sold in the outdoor section of your local store.  A 4 pack on closeout cots under $6 from : http://www.sierratradingpost.com/p/1947V_Grabber-Emergency-Blanket-4-Pack-.html?utm_source=GoogleBase&utm_medium=PaidShopping&utm_term=Grabber_Emergency_Blanket_-_4-Pack_&utm_campaign=PCGOOGLEBASE2KX&codesProcessed=true

82x54" ea.
1.75 oz. ea.

You may also search for
POLYETHYLENE TEREPHTHALATE or POLYESTER FILM, POLYVINYLIDENE CHLORIDE (PVdC) COATED


Looking forward to seeing more on this.  If your final shape is to be a bit more complex, and you'd like to get a flat pattern for your design, let me know and I can hopefully lend you a hand. 

[Vorpal Bandersnatch]

I'm hoping to get a more streamlined, zeppelin-type envelope made eventually. The motors are able to exceed the maximum velocity of the envelope quite easily, and when that happens it skew to one side dramatically and becomes basically uncontrollable until it sheds some momentum. I've actually got some directional stabilizers on it now, but at the low speeds the blimp is traveling they don't have a huge impact.

What I'm hoping to find in terms of an envelope material is something that is heat-sealable, cheap, and air-tight. The standard mylar apparently isn't heat-sealable, and requires pretty delicate application of adhesive to create good seals. The stuff that balloons are made of is actually a coated nylon, which has a heat sensitive adhesive, but I've been having a heck of a time finding a decent supplier. I'd also really like to find something cream colored, to at least give the appearance of canvas. Ultimately I'd like to make a gondola out of balsa and use some lightweight string/netting to attach it to the envelope, because it would look a lot cooler, but also be much more durable. The current adhesive setup is less than ideal.

Another question - is it possible to paint this type of material? I'm not terribly handy and I don't have a huge weight budget (about 200 grams total) so I'm hoping for some kind of spray paint, but I'm worried that standard paint won't adhere very well to the slick balloon material.

Also, in terms of power supply, I've got a number of 7.4V li-ion packs that power it. The nice thing is, blimps are pretty efficient as far as aerial transportation goes, so I can run for quite a while on a 460 mAh pack.

The main difficulty with autonomous control is basically a continual overcorrection problem, because a simple mechanism like "blow left when x, blow right when y, blow forward when z" will cause the blimp to rotate back and forth and spin around like a crazy thing. Instead, it needs a pretty sophisticated control mechanism that can look at spin rate and changes in altitude, and apply forces appropriately to modify those quantities. That will require much fancier sensors, which will cut into the money and weight budget. I do have a compass available to use, though, and I'm thinking that I could look at the rate of bearing changes to get more consistent behavior.

Really, though, now that I have this done, I've found that airships are just as fascinating and fun in practice as they seem to be in fiction. People are really impressed and intrigued if I take the blimp out in public. It flies with a wonderful mix of serenity and awkwardness, and it is actually a pretty therapeutic experience to fly it around. More advanced models will certainly have to be made...

[SPBrewer]

I predict that R/C Airship competitions are in the near future.

                                        The Sky Pirate
                                        Captain of the "Queen Victoria's Revenge"

[Capt. Dirigible]

I predict that R/C Airship competitions are in the near future.

                                        The Sky Pirate
                                        Captain of the "Queen Victoria's Revenge"

We had them at Asylum!

[nicromanov]

excelent! we need more of this sort of thing ,much much more .
 keep up the good work old chap

[tophatdan]

i keep seeink kits for these in the back of magazines, pretty cool.

[The Inventor]

That is awesome !

I've even seen that vid on youtube when I was looking for ideas for construction of my own machine.

Please keep posting.

[Otto Von Pifka]

maybe a mylar bulkhead to help shape the envelope?  a disk with a diameter slightly larger than the diameter of the envelope in the middle could be held in with small pieces of tape spaced along the diameter of the disk. chances are the evelope would take a more banana shape but having the bulkhead near the motor plate would firm up the torque effect. moving the motors inboard would reduce the wobble but it would also reduce the amount of steering action they have.

the inside of a blimp envelope is actually pretty complex.

http://www.redorbit.com/news/science/386540/employees_build_tension_inside_goodyears_blimp/

http://science.howstuffworks.com/transport/flight/modern/blimp1.htm

[Vorpal Bandersnatch]

I liked those links - I wish the first one had some pictures of the cables.

I've seen some places that have pretty cheap carbon fiber struts, and I've thought that if I could use just a few of those and make my own envelope I could make something more stable and aerodynamic. I particularly liked the part about the ballonets - if I could find a way to electronically alter the buoyancy life would be so much easier. Right now I'm using a machine bolt and varying the number of nuts on it to try to get the blimp neutrally buoyant. It looks like their system relies on the fact that the envelope is pressurize to it's maximum size, more or less. I would need to build a very durable envelope to try anything like that, because my current one has to be underinflated a fair amount to prevent it stretching and developing leaks. There are a handful of times that it has gotten pretty warm and the pressure has created some microscopic holes along the seam, so now I've got to top it off much more frequently.

I've considered using water or little pellets for ballast - if I was really clever I could create a ballast system and armament all in one.

[greensteam]

This is the one I aspire to:

http://zzz262.multiply.com/video/item/2663

The one person indoor blimp.

[Vorpal Bandersnatch]

This is the one I aspire to:

http://zzz262.multiply.com/video/item/2663

The one person indoor blimp.

I've seen that before - pretty fantastic. Probably the closest to direct human flight that we'll ever get. Unless, of course, we colonize a planet with lesser gravity and greater atmosphere density.

[Thomas MSwift]

  Lower gravity and higher atmospheric density are mutually-exclusive things, I believe...Nice idea, however, for an indoor stadium. Aerial races, anyone?
  How about a larger version with multiple "wingmen"?

[Vorpal Bandersnatch]

  Lower gravity and higher atmospheric density are mutually-exclusive things, I believe...Nice idea, however, for an indoor stadium. Aerial races, anyone?
  How about a larger version with multiple "wingmen"?

The atmosphere could be something like argon or an even heavier gas, which would stick around densely and reliably even on a lower gravity planet. I think someone postulated that one of Jupiter's moons has a situation roughly similar to this, in which a human could strap on wings and take flight. At least as long as your oxygen supply lasted.

Also, I think a model airship race would be fantastic! Could you imagine if we held one at a convention? Maybe we could have some manner of betting, get an official rule set, etc. Lots of fun. Especially as we'd then have a fleet of airships to terrorize the skies.