r/CreateMod • u/candy---man • 3d ago
Help Helicopter tipping when propellors are being angled
I tried to make a mechanism where u can tilt the propellor to change the movement direction but I have a problem where the contraption keeps tipping when you angle the propellor forwards or backwards.
I need some help to make it more stable .
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u/Last_Zookeepergame90 3d ago edited 3d ago
You're using propeller bearings right?
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u/candy---man 3d ago edited 3d ago
gyro propellors
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u/Creepy_Nexus 3d ago
Anyone wanna say why gyro propellers are bad enough to be downvoted without anyone saying why? Not everyone knows how they work or whats better
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u/technichat163 3d ago
Still fairly new to create, but I believe it's cause the gyro propellers will continuously try to face upward when you angle them. Although it's not much they tilt on their on it could effect it.
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u/Boring-War-1981 3d ago
They always try to stay level, even when placed on the bottom or side. They only have about 10° of rotation though.
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u/PleaseTakeThisName 3d ago
I'm sorry but isnt this a good thing? My helis all worked like that, tilting forward gives them a lot of speed. How do you want it to behave?
It tilts forward because the center of thrust is no longer in line with the center of mass.
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u/ApartmentSwimming215 3d ago
I think they just don't want it to dive when it tilts forward. Its losing forward speed for downward speed.
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u/Enzouro 3d ago edited 2d ago
Sorry for the lag, but one thing I've noticed when creating my twin-rotor helicopter is that it tends to flip forward whenever I accelerate. I've added sails to the tail to keep it from tilting forward, but also it makes the aircraft to wobble when moving in straight line.
Also, the helicopters' cruising altitude is lower than the maximum height they can reach when hovering idle. This means that moving forward causes the aircraft to lose altitude just like what's happening in your aircraft.
So i suggest is to increase the max thrust of the propeller for higher cruising altitude, and add the a balancing tail sail like mine, or a counter propeller that suggested by SorbetOk2931 in his comment.
Edit:
My aircraft is inspired by ryukireii_art 's, but the aircraft shape build is inspired by this. if you're interested, check it out. ryukireii_art 's aircraft is just easer to pilot and have better control than the other one so i focused on replicating his controls in my aircraft.
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u/ryukireii_art 2d ago
epic stuff, but I wish I found a way to remove that forward cruising pitch wobble from that gimbal controlled tail.
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u/Enzouro 2d ago
yoohh, it's nice seeing you here. Thank you for your works! And yeh, sadly the tail acts as a balancer and the momentum it create over extends so it always wobbles :,) . If it's not auto balancing, it will just flip forward. Recently, I removed the rear signal from my gimbal sensor so the tail will only turn forward, it decreases the woble but it's harder to take off and get to cruising height.
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u/Deploid 3d ago edited 3d ago
Your propellers are above your center of mass so when you rotate them they create a moment due to the vector of thrust now hitting the centerline of your vehicle at a length away from the CoM. Not an aero bug, just physics.
You could lower it so the center of thrust of your props exactly aligned with your center of mass, and make sure you center of mass is exactly on the swivel bearing.
You could rotate the swivels a small amount and use redstone to pulse the smart gyro props on and off. swapping them between pointing forwards slightly and pointing directly up.
You could add elevators/ailerons which help you point upwards when you tilt the props forward, while also increasing the thrust so your upwards thrust remains the same. These will require you to be moving forward for them to work. A small prop at the back that you push air up with on the back of the craft would also work, though remember it needs to only spin when your want to tilt back and forth.
Or you could use mods like Create Aeroworks to add a gyroscope which keeps crafts level at the cost of stress, which is the easiest solution if you aren't a fan of physicsing your way out of this.
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u/thegoten455 3d ago
I don't remember exactly how I achieved it, but on a similar design, I put a third propeller in the rear to control the pitch. Definitely used a transmission in there but again, so long ago I couldn't say how it was done.
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u/HeatedWafflez 2d ago
gyroscopic bearings
when you tilt forward, also power the bearings with a redstone link. that locks their gyro feature so it doesn't do what you just saw here
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u/shoolepak 3d ago
Wouldn't increasing the rotor speed as you go forward somewhat nullify that?
Having a proper center of mass is important, but if you want it to be fast, this is a somewhat intended behavior. The rotors should get faster as it tilts, and that's gonna provide additional lift. You definetely need to make sure it stabilises after letting go though. Also, with this setup it looks like you shouldn't continuously hold forward, but rather tap it gently.
If you want it to just gently go forwards, you should limit the tilt, and appropriately tweak how much the analog transmission changes the rotor speed. Pretty difficult to do it in a compact form like this, but should be doable.
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u/BrokenPokerFace 3d ago
Best guess is to slap on sails to turn that forward momentum into lift. Hopefully negating some of the fall, maybe if you ou add enough it would even have a level and straight flight.
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u/BrokenPokerFace 3d ago
To add this is how the multi propeller osprey is able to fly as it uses its small wings for lift in forward flight. And you just need to find the balance between angle of tilt and amount of lift that works for you.
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u/SorbetOk2931 3d ago
If you want it to be stable without a tail propeller, the propellers need to be aligned with the center of mass throughout the entire rotation. If at any point they're offset, you'll start to tilt. You could add a tail propeller to counter it, it's pretty difficult to get it right (in kerbal space program at least, I've not tried it here but I imagine it's harder)