Fritzing

The most usual Remote Control configuration to  command small aircraft, boats, cars or even robots, uses PPM/PWM coding in a radio link with a suitable transmitter/receiver combination. But sometimes, it is useful to have a processor in the middle of the chain, in order to do more than a simple direct command in real time .   It is what is called as a fly by wire system. The following project is a simple implementation of such a system and suffers from considerable latency and some jitter in the servos. As such, is not suitable for all applications and certainly not for aircraft. Nevertheless, for small robots and boats is appropriate.   It uses the Arduino pulseIn function which is very useful but has certains limitations.

The project uses a six channel RC transmitter receiver set, in the case a FUTABA T6J / R2006GS and four servos. These work with a pulse time between 1000ms and 2000 ms. The neutral point is 1500 ms. The RC receiver is connected to a Arduino Mega 2650 and the pulses are decoded using the pulseIn() function. The outputs are linked to four servos which are connected to PWM pins. The servo.write() function does the rest.