Half a croissant, on a plate, with a sign in front of it saying '50c'
h a l f b a k e r y
Romantic, but doomed to fail.

idea: add, search, annotate, link, view, overview, recent, by name, random

meta: news, help, about, links, report a problem

account: browse anonymously, or get an account and write.



Please log in.
Before you can vote, you need to register. Please log in or create an account.

Powered Frisbees

Take one out for a spin !
  [vote for,

The Easy Glider.
A compound flying disc, like all the models, it has a "counterdisk" tucked away underneath, joined to the shell via a flat electric motor. Switch the motor on and the main disk spins one way, the counterdisk the other. The extra rotational energy keeps the disc level longer for more airtime, and even allows for soft tosses without wobbles.

The solar panel on top adds to the power, and recharges the batteries. Perfect for those long days at the beach.

The Roswell
uses a larger equal counterdisk, exposed to the air. Completely silent, the radio-controlled flying disc easily competes with RC winged gliders on their own terms, riding thermals, soaring, swooping and terrorizing seagulls. A couple of LED's embedded in the rim, and an LED tight-focus "searchlight" underneath, also make it perfect for nighttime flights.

The Super Looper
is designed primarily for indoor use: a 6" diameter very lightweight, compound flying ring, the center portion is spanned by a few thin, fixed-pitch airfoils. Basically, it looks like two Mercedes-Benz hood-ornaments "in flagrante delicto". Alongside acceptable frisbee flight characteristics it can operate as a helicopter, with no need of a friendly updraft to waft it upwards.

The Aerobat
The only powered frisbee to have a moving-parts count greater than 2, the flat vanes on both discs, running from the wide hub to rim, form a completely unbroken surface when feathered (closed), giving it freeflight performance characteristics similar to the glider models. When the fans are opened (in either direction), the Aerobat can translate vertically extremely fast, even faster when the flywheels are spun right up prior.


How they work.

The basic premise of a compound disk is pretty straightforward: the counterrotating flywheels' incidental precessions will cancel out, and the increased rotational energy means increased stability time.

Remote control is a different issue. Frisbees don't have aerodynamic control surfaces They don't even have a definitive front or back. Such things could be duct-taped on, but then it wouldn't be a Frisbee, and the parts count would increase significantly.

What we have is a transmitter and a flying craft (with a receiver). We can draw an imaginary line from operator through the Frisbee and call the far side the "front" and the near side the "back". The process of having the disc "know" what is currently front and back is just a matter of which of the many thin-wire antennae embedded in the rim receive the signal first and last.

We also have two disks, spinning counterrotationally in parallel, like so...
If we then pull them together on one side and apart on the other...
they will both precess in the same direction, relative to the frisbee as a whole.

It's actually physically less complicated than a model airplane setup.

To further explain, the discs (which are splined to the motor) can be differentially tilted by using what amounts to another pancake motor, but with a totally different "firing order" of its electromagnets: one that keeps all the armatures attracting on one side of the assembly and repelling on the other.


... and a couple more models, with slightly different paradigms.

The Halo:
instead of two fans, one on top of the other, two squirrel cage fans with diagonal vanes, one inside the other. Usage similar to the "SuperLooper"

Battle Frisbee
A single (non-compound) discus for destructive aerial dogfighting: lip-embedded ramjets for rotational persistence above Mach 1, rim-countersunk valveless pulsejets for precessional control and a couple of axis ramjets for fast axial translation; solid aluminium, the only moving parts are the fuel-injectors' piezo-pins. Control is the same as Aerobat, despite it being more of a remote-controlled cannonball.

FlyingToaster, Apr 28 2015

Already in production in the Far East https://www.youtube...watch?v=Zad8RuKCl0s
Baked to a crisp [AbsintheWithoutLeave, Apr 30 2015]

An early proof-of-concept demonstrator https://en.wikipedi...iki/Fairey_Rotodyne
[AbsintheWithoutLeave, Sep 25 2015]


       Maybe two or four of these things from a Flying Toaster?
popbottle, Apr 28 2015

       Jet version, please.
pocmloc, Apr 28 2015

       Cool and a lot more ethical than just sticking a load of real bees on the top of it.
not_morrison_rm, Apr 28 2015

       Wasn't that last one part of Oddjob's hat?
lurch, Apr 28 2015

       // Jet version //   

       Rocket. Hypergolic monopropellant. MUHWHAHAHAHA !!!   

8th of 7, Apr 28 2015

       "Oh noes, it won't start !"   

       The "Battle Frisbee" comes with a powered spindle for launching (or you can keep it on the spindle after the ramjets kick in and it's a pretty impressive electrical generator) and landing. Ideal for the upcoming "Flying Robot Wars", hosted by Craig Charles.
FlyingToaster, Apr 28 2015

       NononononononononoNO, no launcher ... it has to be "Pull pin and throw" ...
8th of 7, Apr 28 2015

       You've put most of the customer-service department in therapy, what with the special orders... so, will that be fragmentation, flashbang, or aerosol dispersion ?   

       Do your own testing this time, by the way: we don't want a repeat of "Antitank Spear".
FlyingToaster, Apr 28 2015

       ... hmm... of course, it'd have to be two disks meeting the air, not just one: eventually the outside disk would slow and stop, while the inner sped faster and faster. (except the easy glider: its flight-time is short enough it can just be a regular frisbee with a flywheel bolted on underneath).
FlyingToaster, May 04 2015

       Making them precess in the same direction by pulling together is brilliant.   

       The control could be simpler if there was a non- rotating disc in between. The rotating discs could have magnets all around the rim, north pole facing out. The non-rotating disc could then pull the discs together at a certain point in the circle by energising an electromagnet there with the south pole facing out.   

       Or to pull the discs together at a point in the circle between two of the electromagnets, energise both of them.   

       Or to push the discs apart near an electromagnet, energise it with the north pole facing out.
caspian, Jul 14 2015

       //brilliant// I haven't done enough research to see if it's original. I assume some toy has used it. Originally it was part of an idea (mine) to equip a Flying Flapjack with electric motors, tilting the huge propellers when necessary to keep their precession from interfering with the operation of the aerodynamic control surfaces.   

       The second one you mentioned - two disks with electromagnets - is the one I chose for the post. Control is more complicated than the "neutral disk" method, but that's what electronics (or digitalia) are for. It'd be nice to be able to use the tilting bands as a motor, but they wouldn't be very efficient (since they're relatively far apart).
FlyingToaster, Jul 14 2015

       I wouldn't be too surprised if ships use something like that for stabilising. But I'd like to see a video, especially if there's anything more accessible to individuals, like a toy or a science experiment. I bet it would look really counterintuitive.
caspian, Jul 15 2015

       Well, to illustrate direct precessional control, there's bicycles.   

       A total newbie rider will have problems because they turn the handlebars without tilting the bicycle... and the front wheel precession tilts the bicycle outwards of the turn, ie: the bike turns right while tilting left. (Okay, centripugal force might have something to do with that as well, but bear with me)   

       A more experienced rider can turn the bike by tilting in the direction they want to go, without using the handlebars: the front wheel precession from the tilt automatically turns the handlebars, thus the bicycle, in the proper direction.   

       Also the lawnmower man gimbal machine and some spinning machine at the Science Centre, where you tilt the handlebars up or down and the machine spins around.   

       And there's an annotation to "Vertical Engine" by [baconbrain], suggesting that a friend used precession to pop the tail up on a takeoff run in his Cessna.   

       But direct precessional control from counterrotating disks ? It's sortof necessary for the Idea's frisbees. Though, I suppose you could do it with one disk with little flaps all'round the circumference, which activate in sequence at the same spot while the frisbee spins, causing the disk to precess at 90deg to the aerodynamic nudge. Nice, but lots of moving parts.   

       In my electric Flying Flapjack(wikipedia: V173) half-project(unposted), turning the engines outwards or inwards causes the aircraft to pitch down or up.   

       Unfortunately for that particular half-project, tilting one engine up and the other down, to precess into a yaw, would probably result in a bit of outwards rolling (the same problem as the newbie bicyclist, though not the same cause) from airflow. That could be solved by having the propellers spin the other way(s)(so it would roll inwards while turning), but that would spoil the nift of the FF in the first place (the propeller vortex cancels out the wingtip vortex; now _that_ is brilliant).
FlyingToaster, Jul 15 2015

       Nice work. Very nice work indeed. Revolutionary even.
AusCan531, Sep 25 2015


back: main index

business  computer  culture  fashion  food  halfbakery  home  other  product  public  science  sport  vehicle