Thursday, May 22, 2014

How To Choose RC Transmitter For Quadcopter

http://blog.oscarliang.net/choose-rc-transmitter-quadcopter/

How To Choose RC Transmitter For Quadcopter

Remote Controller Protocol
Before building your quadcopter, the RC Transmitter would probably be the first few things you need to look at. It’s a common question for RC beginners how to choose a decent RC transmitter. In this article I will discuss the basics of a RC transmitter and what you should buy.
Unlike other parts there isn’t much room for you to DIY, so it’s common that we would just buy a commercially available transmitter. There are a few things about functionality you should know before discussing the price.

Channels

You might already often hear the term Channel when talking about RC transmitters. Each channel allows one individual thing on the aircraft that can be controlled. For example, one channel for throttle, one channel for turning right and left, one channel for pitching forward and backward, one for rolling left and right. Four channels is a minimum for a quadcopter (pitch, roll, throttle, yaw).
RC-transmitter-channels
With more channels than just four, you can even have switch, or potentiometers to change settings on the quadcopter while flying. Some fly controllers (e.g. Multiwii, Arducopter) recommend using transmitters that has at least 5 channels, the extra channel is to switch between different flying modes.
5-channel-transmitter-diagram

Modes

There are 2 different Modes – mode one and mode two. It’s basically different control configuration.
The mode one configuration has the elevator control on the left joystick and the throttle on the right one.
The mode two is the most common for quadcopter because the stick represents the movement of your quadcopter. It has the elevator control on the right joystick and the motor throttle on the left one. The right joystick self centres in the both axis, whereas the left joystick only self centres in left/right axis and “clicks” in the up/down axis in order to allow the throttle setting.
transmitter-stick-modes

RC Transmitter and Receiver Paring

A receiver usually comes with the transmitter when you buy it. But be aware that some types of transmitter are only compatible to their own receivers (same brand same model). That means when the receiver is broken you will have to get the same one. There are a few exceptions that they can be paired with other receivers (i think universal is the word?). Make sure you check and ask the shop before buying.

What RC transmitter should I get?

The price range is huge, from as cheap as $20 to over $1000. Of course the cheaper, the lower quality it would be, and the fewer channels you are going to get. It would be a good idea to get a cheap 5 or 6 channel one to get a taste of flying a plane, and later one upgrade to a better transmitter when you know more about the subject. It’s always a good idea to have backup transmitters anyway. However if you are serious about quadcopters and someday want to get one with GPS navigation you will need 8 or more channels.
The transmitter is potentially a long term investment. If you are not sure about whether you will be staying in this hobby, you would be safe to get something like a cheap 6 channel. But if you are sure you will stay in the next couple of years you will not regret to get a 8 channel or more! Moreover It’s not just a matter of number of channels. Some RC transmitters support programming and firmware flashing to enhance functionality as well. So do your research before spending good money on it.

Recommedation on 8 Channel RC Controller

If you ask me that, I current favourite is the Turnigy 9X! See my review about this Transmitter.

DIY RC Transmitter

Although it’s possible to hack a game console and make your own RC transmitter, it seems quite difficult.
I actually also built a RC Transmitter myself although I haven’t tested it yet with a quadcopter.