A new version of the Quadcopter is available at: https://github.com/vjaunet/QUADCOPTER_V3
This project is the development of a code to control a quadcopter with a Raspberry Pi.
Following the Quadcopter V1, I want to use a 4 cahnnel RC remote to have better control on the drone. In fact, the tablet shows quite poor sensitivity that is an handicap for good quality fligths.
Therefore in theis version of the Quadcopter, the RPI will still hold the PID, but a micorcontroller is used to interface the RC receiver and the ESCs. The Rpi aks the microcontroller for RC commands and sends motor speed values through I2C. An Arduino Micro has been chosen as microcontroller, for its compact size and sufficient abilites for the job.
The Raspberry PI hosts:
This project is greatly inspired and using source code from :
https://github.com/richardghirst/PiBits for ServoBlaster that I use to control the ESCs and the MPU6050 Digital motion processing.
https://github.com/big5824/Picopter for the Timing and the code structure
https://code.google.com/p/owenquad/ for the Android app
Many thanks to these people.
Principles
When powered, the Quad is in a locked status so that the ESCs do not turn the motor on. To unlock, simply put the RC sticks to the lower center angle. It can be locked again by doing the same operation. This is handled by the Arduino for more safety.
This projects includes :
MPU6050 -> RPI : -VDD -> 3.3V -GND -> GND -SDA -> SDA -SCL -> SCL -VIO -> 3.3V
Arduino -> RPI : -VCC -> 5V from external Regulator -GND -> GND -MISO -> Logic Level converter ->MISO -MOSI -> Logic Level converter ->MOSI -SCK -> Logic Level converter ->SCK
ESCs and RC Receiver on Arduino: -Using PinChange interrupts -Check in the arduino code