Community > Screenshots & Videos

Marvins Creations

(1/3) > >>

MarvinMan:
Twin rotor helicopter 'Gemini' version 1.0

This is my latest attempt at building a working helicopter. Previous iterations used a fully mechanical cyclic to overcome limitations in code speed. The result of this was a large assembly under each rotor and the helicopter was barely controllable when it ever managed to generate lift for long enough to get off of the ground.

This version is much more light weight and uses a software cyclic which works much better. The system to synchronise the interleaved twin rotors is also massively improved and completely prevents collisions even with asymmetrical loading on the two rotors. The result is a stable platform that replicates all the key functionality of a real helicopter.

It turns out that the tail isn't really necessary, and actually negatively impacts the performance when not flying forward. The bare V shaped rotor assembly would probably happily fly on its own.

Operation/Controls:
C/T- Throttle: This sets the speed of rotation of the rotors, and should be set to full while the helicopter is in operation. The currently set operating speed is by no means optimal, but provides a satisfactory compromise between generating enough lift and not outpacing the cyclic control code.
G/H- Collective: Alters the pitch of all of the rotor blades to increase/decrease the amount of lift generated.
Y/I- Cyclic pitch
F/P- Cyclic roll: The cyclic control individually varies the pitch of each of the rotor blades over the course of each revolution. This causes one half of the rotor to generate more lift than the other, creating torque that alters the attitude of the helicopter.
D/U- Yaw: Acts as a rudder to change the heading of the helicopter by increasing the pitch of one rotor while decreasing the pitch of the other, creating an unbalance in the torque between the two rotors.

Blueprint



And here's what makes it tick. The two big blocks are the phase shifts and sine functions to calculate the correct angle for each blade. On the left are a couple of basic controllers to keep the helicopter roughly level, and the code going to the bottom of the screen is to sync the two rotors.


Close, but no cigar. Really, I'm just impressed that it managed to lift something so huge that far without falling out of the sky.

Sleeping_Owl:
Impressive. Getting things properly synchronized is usually a problem.
To avoid problems with code speed you can increase rotor's lift - put more fins on each blade or make blades longer so that fins have more linear speed at the same angular speed.

cupid_the_conqueror:
ladies and gentlemen the marvelous marvin never fails to impress! unlike me.. god the goblinABRT was bad..

z26:
Wow, lifting that spherical wheel thing from pressureline... the power and control to carry something like that (that probably wants to oscillate all over the place) is impressive




--- Quote from: cupid_the_conqueror on December 01, 2016, 05:36:26 am ---ladies and gentlemen the marvelous marvin never fails to impress! unlike me.. god the goblinABRT was bad..

--- End quote ---

At least YOU did something :p unlike someone else that hasn't even entered that acl thing

tob.s:
Impressive, it always amaces me what people can do with maths, some hundred years ago people with my math-knowledge would have burned you for this though  ;D still not sure if theres no magic involved

Navigation

[0] Message Index

[#] Next page

Go to full version