Flight Control is Key to Success

The most difficult thing about flying is to keep control of the aircraft at all times. For this you need either a capable pilot, or a powerful flight computer, which has the necessary sensors (IMU, GPS, lidar) to check and correct the flight attitude and position at any time. Ideally you have both.

The first flight tests with both the prototype and the full-scale FlyRider aircraft will be carried out remotely (for the prototype test flights there is no choice since its unmanned, for FlyRider ist just for safety reasons). This requires a powerful and absolutely reliable remote control technology: I will use the "FrSky R9" hardware (R9 transmitter module and R9 mini receiver) running the open source software "expressLRS".

FrSky R9 RC transmitter

This R9 tramsmitter and receiver combination from Frsky can be operated with the open source software expressLRS and, in addition to high range and low latency, offers the possibility of transmitting telemetry data back to your transmitter. 

FrSky R9 features:
  -  868MHz working mode
  -  Long range, low latency and high precision RC system
  -  redundancy function
  -  Telemetry mode(25mW) and non-telemetry modes (200mW / 500mW) are available
  -  Smart Port enabled and support telemetry data transmission

Express LRS

ExpressLRS aims to provide a completely open and reliable radio control link for a maximum range and very low latency.

For more information on expressLRS refer to: https://www.expresslrs.org

Pixhawk 2.4.8 Flight Controller

Initially “Pixhawk” was a student project at ETH Zurich. Little did the team know that it would end up having such a large influence on the drone industry. Today pixhawk is one of the leading flight controllers for UAVs and drones. 

Some technical data:
CPU:
    32 Bit Arm Cortex, 216MHz, 2MB memory, 512KB RAM
On-board sensors:
    L3GD20 3-axis 16-bit digital gyroscope
    LSM303D 14/3 Axis Accelerometer Magnetometer
    MPU6000 6-axis accelerometer / magnetometer
    MS5611 high precision barometer

Interfaces:
    8-16 PWM outputs (8 from IO, 8 from FMU)
    5 general purpose serial ports
    3 I2C ports
    4 SPI buses
    Up to 2 CANBuses for dual CAN with serial ESC

Ardupilot

Pixhawk is a sophisticated flight controller, but only the hardware. Without suitable software it just can't work! Fortunately, there is a variety of software that can run on Pixhawk, my choice is "ArduPilot". ArduPilot is one of the most advanced and reliable open source autopilot software available, it has been under development since 2010. The software is capable of controlling almost any vehicle system imaginable, from conventional airplanes, multi-copters and helicopters to rovers, boats and even submarines.

Mission Planer

Mission Planner is a full-featured ground station application for ArduPilot. It runs only on Windows. Mission Planner can be used as a configuration utility or as control supplement for ArduPilot controlled vehicles. 

Important Features:
- Firmware installation into the flight-controller hardware (i.e. Pixhawk)
- Vehicle setup and configuration, performance tuning
- Planning of autonomous missions with simple point-and-click way-point entry on maps.
- Download and evaluation of mission logs created by autopilot.
- FPV (first person view) operation
- Vehicle status Monitoring while in operation.

Make sure that you install the correct firmware on your flight controller hardware. The manufacturer strongly recommends to use only the firmware "FMUv3" with Pixhawk 2.4.8.