Portable Flyer - PatATi asymmetric transfer & intake in 2strokes

[manolis 0]

Hello.

You may like to think (or dream) about this application:

[Url]http://www.pattakon.com/PatAT/PatATi_OP_props.gif[/URL]

[Url]http://www.pattakon.com/PatAT/PatATi_half_OP.gif[/URL]

It is an Opposed-Piston PatATi Portable Flyer having

80mm bore,

80+80=160mm stroke,

800cc,

540mm crankshaft axis to crankshaft axis distance (two directly-driven
counter-rotating propellers, 1m diameter each),

perfectly "vibration free" and "reaction free" structure,

total weight less than 15Kp (33lb).


The second GIF is the one half of the Opposed Piston PatATi engine and shows
the "internals".

The narrowing at the center of the cylinder of the OP PatATi engine enables
a compact combustion chamber without spoiling the - loop - scavenging. The
spark plugs are located more centrally. The narrowing causes the required
squeeze during the combustion.

Without phase difference between the two crankshafts (yet, with asymmetric
transfer and intake) and with the same instant pressure acting on the two
piston crowns (common combustion chamber), the synchronizing mechanism (not
shown) between the two crankshafts runs unloaded, so it can be lightweight
and reliable, causing minimum power loss.

The two counter-rotating propellers act as the flywheels of the engine.

With the two oppositely moving pistons counterbalancing each other, the
balance webs on the crankshafts have to balance only the mass of the
crankpin and of the rotating part of the mass of the connecting rods
(lightweight and compact crankshafts).

At 5,000rpm the speed of the blade tip of the 1m diameter propellers is
260m/sec.
With 0.5Kg reciprocating mass per piston (it includes the mass of the
piston, of the wrist pin and of the "reciprocating part - typically 1/3 - of
the connecting rod) the resulting maximum inertia force is 700Kp at the TDC
(at the BDC the inertia force drops to 400Kp; con-rod to stroke ratio: 2).
In comparison, with only 20 bar pressure inside the cylinder (20 bar is the
BMEP - brake mean effective pressure - in the typical marine two-stroke
supercharged engine), the resulting pressure force on each piston is
1,000Kp.


For more about the PatATi Aymmetric Transfer and Intake:
[url]http://www.pattakon.com/pattakonPatAT.htm">http://www.pattakon.com/PatAT/PatATi_OP_flyer.gif[/URL]


Application:

Imagine a pilot / rider wearing a wingsuit and having secured on his
shoulders this Portable Flyer, flying only 2m above the sea (for safety)
from island to island.

The pilot / rider can take off vertically, like a helicopter, and then he
can progressively turn to horizontal fly, like an airplane, to cover the
distance quickly and fuel efficiently (fast and cheap).
At landing he returns to "helicopter" mode to land vertically.

For more about the PatATi Aymmetric Transfer and Intake:
[url]http://www.pattakon.com/pattakonPatAT.htm

Thoughts?

Thanks
Manolis Pattakos

[Hellis 0]

You secure it to the shoulders and those spinning blades above your head keeps you flying?

But that will chop of at least 3 GoPros.

[Alexg3265 0]

Yes!! Have to have adequate go pro clearance! How high will they go and will they return to home when you un strap it and free fall to work every morning? I fly drones and I've seen some heavy lift ones... That's what we need just an automated multirotor and voila! Personal jump machine! Hehehehe

If someone wants to find me I'll build one!

Edit to add:
http://www.youtube.com/watch?v=L75ESD9PBOw
http://www.youtube.com/watch?v=6rK2Url7UBQ

And actually, there's something called an volocopter. Look it up. 18 rotors or something if I remember correctly. The benefit to many rotors vs, just those two is that an 18 rotor design has a computer that will redirect thrust and you won't even realize if up to (4?) motors failed. Whereas if this fails, you better hope you have a rig on and you have altitude. It needs some sort of redundancy or failsafe....

I was that kid jumping out if his tree house with a bed sheet. My dad wouldn't let me use the ladder to try the roof...

[manolis 0]

Alexg3265

Yes!! Have to have adequate go pro clearance! How high will they go and will they return to home when you un strap it and free fall to work every morning? I fly drones and I've seen some heavy lift ones... That's what we need just an automated multirotor and voila! Personal jump machine! Hehehehe

If someone wants to find me I'll build one!

Hello Alexg3265.

We are building a full size PatATi Opposed Piston Portable Flyer (800cc). If you need the drawings e-mail me.



As I wrote in the first post, the PatATi Portable Flyer is a:

perfectly "vibration free" and "reaction free" structure.


Let me further explain these terms.


The Wankel engine can be, "inertially", a perfectly balanced engine, however it cannot bet a "perfectly vibration free" engine / structure.

Consider the case wherein your paraglider (or your ultralight) is having a Wankel rotary engine driving a propeller.
At each combustion / expansion the propeller accelerates and the rest structure, including your body, inevitably receives a reaction torque pulse.
Think what happens at a sudden opening or closing of the throttle

Consider now that your paraglider (or your ultralight) is having a PatATi Opposed Piston engine driving two counter-rotating symmetrical propellers.
As happens with the Wankel rotary, the PatATi OP is, “inertially”, a perfectly balanced engine.
But it is also a "perfectly vibration free" structure.
During a combustion/expansion, each piston, through the respective connecting rod and crankshaft, accelerates its own propeller. The casing receives a "reaction" torque in order to accelerate the one propeller and an equal and opposite reaction torque in order to accelerate the other propeller. The two reaction torques cancel each other inside the casing of the engine. This way the basis of the engine, i.e. the rider / pilot / frame, remains perfectly rid of inertia and of combustion vibrations (common combustion chamber, same instant pressure acting on both piston crowns, zero phase difference between the two crankshaft).
The sudden opening or closing of the throttle cannot de-stabilize the structure any longer.



Consider now the PatATi Opposed Piston Portable Flyer.

With the two propellers (and flywheels) rotating at opposite directions (like two symmetrical gyroscopes), the structure has, according the theory and the experiments:
“no gyroscopic stabilization (acts just as if the gyroscopes were not spinning, ie., the gyroscopes fall over exactly as when they are not spinning - zero net angular momentum)” (quote from Physics Forums at http://www.physicsforums.com/showthread.php?t=173215 )

So, either the two big propellers (1m diameter each) rotate at 5,000rpm, or at 2,000rpm, or they are slow revving or they are completely stopped, the pilot / rider “sees” the same difficulty in order to change the direction of the Portable Flyer (and, so, the direction of the thrust force).
And this is quite important for a stable flight.

Thanks
Manolis Pattakos