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Electronics => Electronics => Topic started by: MangoBot on June 28, 2010, 08:54:44 AM

Title: tricopter RC
Post by: MangoBot on June 28, 2010, 08:54:44 AM
i am very new to RC and i have been looking for a RC transmitter and receiver pair that would be able to control a Tricopter that uses 3 dc motors and a servo for yaw movement. Any help with what I would need, how many channels, if i need gyros, pretty much any info on the electronics
Title: Re: tricopter RC
Post by: Joker94 on June 29, 2010, 02:31:44 AM
well i would go for what you might want in the future not what you need now. therefore approximately 6.

as for this project it depends if you want all of the motors hooked up to 1 channel or if you want each motor to have to ability to have a different speed. after this it is upto you to work out how you are going to control the tricopter. i am not sure if a standard heli set up will work or if you will have to design your own control system.

Have you had a look at how other RC chopers work?
have you got any designs or ideas?

as for the original matter i would say if you can go for a 6 channel radio it has the most diversity and will allow you to add new features to your tricopter in the future. I say this because it will depend on your desing and as you dont have a design at the moment it is worth going with the extra channels. and good for the future.

I have heard good things about the spektrum Dx6i in the US. but some horrible stories in Australia when it comes to rc planes and heli's due to the Australian radios come with the UK power settings which are low giving lower range than the US radios. if your in the US i would go for the Dx6i as it is a good radio.

http://www.robotmarketplace.com/products/0-SPM6600.html (http://www.robotmarketplace.com/products/0-SPM6600.html)

with the extra switches it is also good as it gives you more options when programming. ans it comes with the appropriate receiver.

cheers

Joker94
Title: Re: tricopter RC
Post by: TrickyNekro on June 29, 2010, 03:58:33 AM
Would it be a hovering vehicle... cause 3 is not a good number....

You need even number of motors to counter inertia... Else you need to make, many calculations....
Which are not so pleasant, like propeller vertical axis torque and propeller torque as it is, weight ratios, and so on....
It's basically good to stay off the 3 or 5 or 7 or whatever 2n+1 idea.... it's bad....

Unless you are building a plane, so a gyro at the roll could do the trick ;-)
Also I've heard that, non head locking gyros are better for that task cause they give you better control over the plane ;-)

That's it...

Basically, it wouldn't hurt if you just wrote a word more or two about your project ;-)
Title: Re: tricopter RC
Post by: Razor Concepts on June 29, 2010, 05:09:40 AM
Gyros are needed, you would need at least four (one for each motor, one for yaw)

Three motors is actually not that hard. The yaw servo tilts one motor to control the yaw, which is pretty easy. The ros should take care of the stabilization.

Basically, with a computer radio ( dx6i or dx7), four gyros, and a lot of servo v-tail mixers, you can make a stabilized tricopter without any custom electronics.

Also, brushless motors will be much better and cheaper.
Title: Re: tricopter RC
Post by: Joker94 on June 29, 2010, 05:39:37 AM
i have the Dx7 and really like it. it has 5 or 6 mixes so that would be enough to do the mixes you want.

overall if you have the extra cash go for the Dx7, i am a lot happier i went with the Dx7 over the Dx6
Title: Re: tricopter RC
Post by: MangoBot on July 04, 2010, 09:55:54 AM
im pretty low on cash, and im going for the general tricopter design, three motors going the same speed, the rear being tilted side to side so that the copter spins. It will work like a simple 2channel rc helicopter. The front will be weighted so it will go forward. the rear will adjust which direction it goes forward, pretty much as simple as a tricopter can get