Components of Our UROV TRITON – Part 6 (Flight Controller)

The Pixhawk (V2.4.8) is an expansion board that plugs into the Raspberry Pi 4 and turns it into a fully featured flight controller, ready to power ROVs. At its core, the Navigator is a collection of inputs and outputs. It has inputs from onboard sensors, outputs to servos or speed controllers, and expansions ports that can be connected to external devices.

Onboard the Pixhawk has:

·L3GD20 3 axis digital 16-bit gyroscope

·LSM303D 3 axis 14-bit accelerometer /magnetometer

·MPU6000 6 axis accelerometer / magnetometer

·MS5611 high precision barometer.

Additionally, the navigator has expansion connectors available. Also, the Navigator has a number of important features that are worth highlighting:

– Advanced 32-bit CortexM4 ARM high performance processor, can run RTOS NuttX real time operating system.

– Integrated backup power supply and failure backup controller, the main controller can be safely switched to backup control.

– Provide redundant power input and fault transfer function.

– 14* PWM/ actuator output.

– Bus interface (UART, I2C, SPI, CAN).

– Provide automatic and manual mode.

– Color LED lamp.

– Multi tone buzzer interface.

– Micro SD to record flight data.

The ArduSub firmware is loaded onto the autopilot board (also known as a flight controller). The autopilot processes the pilot input and sensor data, and controls the motors, lights, servos, and relays on the vehicle. It contains embedded IMU(s), magnetic compass(es) and gyroscope(s) to determine vehicle’s orientation. It is also capable of saving vehicle logs.