UAV and drones require flight control software and hardware elements that will allow the aircraft to be controlled remotely either directly by a pilot or autonomously by an onboard computer. UAV flight dynamics are highly variable and non-linear, and so maintaining attitude and stability may require continuous computation and readjustment of the aircraft’s flight systems.
Elements on the ground will form part of a Ground Control Station (GCS) and may include a modem and datalink for communicating with the UAV, a joystick for manual control of the aircraft and GCS software. Elements on board the aircraft include the autopilot, a datalink for communicating with the GCS, and peripherals such as external magnetometers and GNSS receivers.
When working in manual mode, the modem and datalink will transmit commands from the joystick and other GCS controls to the UAV in order to activate the required aircraft systems. For fixed-wing UAVs, the pilot may be manually controlling the elevator, aileron, rudder and throttle. For helicopter UAVs, manual control can act on cyclic, collective pitch, rudder and throttle.
UAV autopilots allow fixed-wing and rotary drones to automatically takeoff and land, execute pre-programmed flight plans and follow waypoints, as well as hover in place (for rotary platforms) or circle a particular location (for fixed-wing platforms). They may also utilise UAV payloads and gimbals such as cameras and sensors.
UAV autopilots may gather information from an Air Data System (static and dynamic pressure), GNSS receiver or Attitude and Heading Reference System/AHRS (roll, pitch and yaw data). A flight control computer (FCC) will use this data to guide the UAV to its next waypoint, activating the required servos, actuators and other control systems, and steering the aircraft in the required direction. The FCC may also operate UAV payloads and communicate with the GCS.