Need Help on DIY RC aircraft/helicopter

[boonyeo]

I am currently in the process of building The Bat from The Dark Knight Rises movie,I have a blueprint and am hoping to cut it.I have now building a small size bat is about 370mm by 260mm, But not know the ideal size.915mm by 610mm which is about 3ft by 2ft and 610mm by 310mm which is about 2ft by 1ft.........

Thank

[quadflyer]

It sounds like a very interesting project, it will be a unique model.

I've seen a few "bat plane" RC models on YouTube but nothing based on the new hovering "Bat".

Will it be aircraft, heli or multi-rotor based.

Will you be posting up photos of the build as you progress?

[boonyeo]

Need Help on DIY RC aircraft/helicopter

F.Y.I

Someone is also building a bat from the movie dark knight. The title is call Hybrid quadrotor: The Bat
Go to http://www.rcgroups.com/forums/showthread.php?t=1817662
From what i see is a heli/multi-rotor based .......

[quadflyer]

Are your following that design.

It looks like a hybrid multi-rotor using a mixture of normal motor/prop & EDF. It looks a very complex idea, being able to control & balance the thrust from prop & EDF motors to ensure stable hover & flight will be a challenge. Finding the right flight controller board will be very important.

I would tend to agree with the suggestions on the rcgroups forum, build a "stick" chassis to test the motor configurations, get that flying, especially since its not a "normal" multi-rotor configuration such as a quad or hex or tri. Once you have a flyable frame, then build the "Bat" body-work onto it.

My first attempt at a quad-based RC model, a copy of the Avatar C21 Dragon quad gunship, was built with a "stick" chassis to make sure I had a flyable basic frame, I then built a balsa-wood body onto the frame.

I hope this helps and I look forward to hearing about your progress.

I'm sure there are lots of very experienced multi-rotor builders/flyers that will be happy to help you.

[boonyeo]

Need Help on DIY RC aircraft/helicopter

Hello
I not following the design,that bat Frame Construction is make of Balsa Wood,Bass Wood and some carbon fiber parts.
My is make of Depron foam board i bought it from one of the store at FookHai Building.It make out of two part.

First is the main body it come with the front part of the bat,second part is the wing part.
I still trying out and will use the idea on the Avatar C21 Dragon quad gunship http://www.youtube.com/watch?v=5hlgQaqOJ_Q

Thank I will keep update on the progress ...........

[quadflyer]

what motor configuration will you use?

I'm always interested in unique aircraft, especially multi-rotor based.

I've seen YouTube vids of Avatar Dragon, Avatar Scorpion, Terminator Hunter Killer, Avengers S.H.E.I.L.D. flying aircraft carrier, all of which were built using multi-rotor motor configurations.

[elmosan]

what motor configuration will you use?

I'm always interested in unique aircraft, especially multi-rotor based.

I've seen YouTube vids of Avatar Dragon, Avatar Scorpion, Terminator Hunter Killer, Avengers S.H.E.I.L.D. flying aircraft carrier, all of which were built using multi-rotor motor configurations.

Its amazingly in tricopter configuration. Front 2 rotors, back big rotor.

[boonyeo]

Need Help on DIY RC aircraft/helicopter

What motor configuration will I use
Good question can anyone recommend me ????????

Will being looking for the following Accessories where can i buy it.

1) flight controller board
2) PROPELLERS - MULTI-ROTORS
3) Motor normal prop/EDF
4) ESC (Speed controller)
5) Batteries
6) Self Balancing Receiver
7) RADIO TRANSMITTERS

Did I mis any out .......

[Super-Hornet]

The possible design to this craft I suspect...

The center big rotor is a coaxial rotor that provide the main lift. Coaxial that cancel the counter rotation. Due to the position of the main rotor is at slightly at the rear..thus, head is heavy. This will tilted the craft forward. To counteract it or to balance it up, two smaller rotor on the front that spin opposite each other. To fly forward, frontal rotor reduced in speed or pitch. Fly backward, increase frontal rotors increase in speed or pitch. Yaw is achieve by adjusting center coaxial rotors or if it is propeller design, varies the center coaxial propellar.

[boonyeo]

Need Help on DIY RC aircraft/helicopter

Possible design :
1) One coaxial rotor at the rear,two normal multi rotor on the front
2) Two normal multi rotor on the front and rear
3) Two normal multi rotor on the rear,two EDF motor on the front
4) One coaxial rotor at the rear,two EDF motor on the front

Any other design ??????

[quadflyer]

I would suggest using normal multi-rotor configurations.

Here's a nice motor configuration that might be suitable for the Bat,

http://www.youtube.com/watch?v=azJST9eG8W8

I've read various comments on other RC forums that EDF are very difficult to balance the thrust when used on multi-rotor, they are also very power hungry compared to normal multi-rotor.

This is the only EDF multi-rotor I've seen on YouTube.

http://www.youtube.com/watch?v=Ts6bhl9bpWA

Mixing normal multi-rotor and EDF on the same quad may cause lots of balancing issues.

I hope this helps

[boonyeo]

Need Help on DIY RC aircraft/helicopter

Let said if I use either axis/Y frame,I will use either all multi rotor motor or EDF motor system.

Example
1) Using multi rotor all pointing down like normal.
2) Using EDF sysyem one/two pointing down from the rear and two normal front

Using all multi rotor balancing all equal normal and also same when using EDF system,but EDF more power than the Multi rotor.
So can I said when using EDF on the either axis/Y frame i have to use ESC (Speed controller)/Self Balancing Receiver
because of the power of the EDF motor.
Just my theory how do you all think ???????

[boonyeo]

Need Help on DIY RC aircraft/helicopter

Current state of today
I will continue updates as the build goes on so if anyone has any pointers on what motors would be best to use or any other tid bits on building and electronics,would greatly appreciate any input given .........

[boonyeo]

Need Help on DIY RC aircraft/helicopter

Continue updates ...........

[boonyeo]

Need Help on DIY RC aircraft/helicopter

Share some inform on the rcgroups.com

I have a question concerning outrunners and lift. generally the lower the kv the more weight the quad can lift correct? or in other terms more lift? That's what I have been informed. I originally thought the higher kv, the better the lift. I still am only able to use about a 10" prop. I could stretch it out to an 11" but that's almost with the props touching...

so far the frame weighs in at 390 grams. I'm thinking it will end up at close to 800 grams, maybe a 100-200 grams more than that even after paint and everything.

You are close. The lower KV allows you to use larger props, which produce more thrust per watt.

So, you can either produce more thrust by increasing your prop size (or disk loading) or by increasing your power output of the motor.

Think of it this way, F=MA. Simple physics. F = force of thrust. Thrust is related to the mass of air and how much you accelerate that mass of air. Because kinetic energy = 1/2mv^2, increasing the acceleration, or change in velocity, requires the quadratic growth of energy. Increasing the mass of the airflow merely requires the linear growth of energy.

Now, imagine the thrust you need is fixed for a hover, simply the weight of your aircraft. That means, if you adjust the M in F=MA, the A can decrease. Because you are quadratically decreasing the energy needed due to delta V (Accel) and only increasing the energy with a linear relationship, overall it requires less energy over time (power) to produce the same amount of thrust.
ilektron is offline Find More Posts by ilektron

Last edited by ilektron; Feb 15, 2013 at 08:27 PM