Hi, I am building my own quadcopter and I need a RC controller, i went to my local store and they have this controllers: Jr Xp7202 6 Channels and Lanyu 5 Channels 2.4Ghz but the thing is that both controllers were made to work with planes and helicopters, should i buy one of the two? CAN I USED IT IN MY QUAD?
Please HELP!
The control simply sends signals to a receiver and it is up to the builder what is done with the output of the Rx.
Look at what the Tx can control and think about how to make your Arduino do what you want it to do from the signal received.
Weedpharma
weedpharma:
The control simply sends signals to a receiver and it is up to the builder what is done with the output of the Rx.
Any RC should work?
I am not greatly knowledgable on RC so cannot say definitely.
The Tx sends pulses of varying length dependent on knob position and this is received and sent to the servo. The servo position is dependent on the length of the pulses.
You need to work out what to do with the pulses in order to control your device.
You also need to consider if the control knobs will give you the specific controls you want.
Weedpharma
Most of these transmitters output a PPM (pulse position modulation) signal, where the relative timing of short pulses indicates several different signals. One PPM signal can be turned into several PWM signals, suitable for control of RC servo motors, using a simple digital logic chip, like a 4017 decade counter.
Getting a PPM signal accurately into a microcontroller is tricky. A few libraries exist, or you can try to roll your own. In fact, I recently wrote a library called "PulsePosition" which does this. As far as I know, it's the only library which is capable of receiving more than 1 PPM signal simultaneously (for example, if you wanted two or more remotes at the same time). The very best way to measure the PPM signal is using the input capture feature on a hardware timer. That gives very accurate readings, even if interrupts are temporarily blocked at the moment the waveform changes. The easier/simpler (but less accurate) way to write this code involves using a pin change interrupt, which then reads a timer or the micros() function. The interrupt response can vary, especially if you're sending serial data or using other libraries that also need interrupts, because they delay the pin change interrupt which causes the code to read the timing later than it should. Of course, you can also just write a loop that repetitively reads the pin, but then your program can't do anything else while the pulses are arriving.
Maybe this helps? Or maybe not, but perhaps it'll give you some terms to use for searching on google?
Hi. Do you mean you need a transmitter/receiver? If so, maybe go with the JR. They have a good reputation.
Also, both TX'es will probably be usable with a quad. What control unit are you using? Ardupilot, MultiWii, CC3D, KK2?