Integrating the Microcontroller onto the Aircraft

Overview

In this brief post, I'll talk about the hardware steps taken to mount the microcontroller, capable of switching modes and communicating directly between the receiver and servos, onto the aircraft as a free-standing system. 

Small aircraft with microcontroller controlling control surfaces

Solder Board

Once communication between the microcontroller, servos, and receivers was working, I put together a small solder board to replace the breadboard so that everything could be cleanly mounted to the aircraft. This solder board used 300 Ohm resistors to protect the input pins. It also used groups of three pins to allow the PWM connectors from the servos to securely connect.

Power

The servos and microcontroller both used 5V power. The ESC that connected to the throttle and battery had a BEC that connected to the receiver to power the servos. By connecting this to the throttle port on the receiver and connecting power and ground pins from the battery port on the receiver to the Vin and GND pins on the microcontroller, I was able to power the microcontroller off of the battery. This provided enough current to run the servos and the microcontroller. However, the one danger was that by connecting directly to the Vin and GND pins, I was skipping over the protective circuitry used on the microcontroller. In the future, I will add this protection back in.

Conclusion

At this point, I knew that I could control the aircraft using onboard power and mountable electronics. The next step was getting something ready to fly.