MP2128g2 flight-control computer

The MP2128g2 is a flight-control computer for unmanned aircraft, made by MicroPilot. It is a complete autopilot on a single circuit board: the processor, the three-axis gyros and accelerometers, the GPS receiver, a pressure altimeter and a pressure airspeed sensor are integrated, so the airframe needs only servos, a power supply, a GPS antenna and a data link to be flown autonomously. MicroPilot positions it as its premium autopilot for high-performance miniature UAVs and keeps it upward compatible with the MP2028g2.

The board is small and light. The maker quotes a mass of 28 grams and a size of 4 cm by 10 cm for the autopilot, and the specification table gives 26 grams including GPS receiver, gyros and sensors, without the GPS antenna, with dimensions of 10.0 cm by 4.0 cm by 1.5 cm. Power consumption, including all sensors and the GPS antenna, is 140 mA at 6.5 V and the supply voltage range is 4.2 to 26 V, so it can run from a single-cell lithium pack up to a six-cell pack without a separate regulator for the autopilot. A separate servo battery supply and separate voltage monitoring of the main and servo supplies are supported.

The processor is a 150 MIPS RISC device, a 50-fold increase in processor power over the MP2028g2, with double the memory and twice the input and output channels. In flight, the controller performs GPS waypoint navigation with altitude and airspeed hold, and it supports up to 1000 waypoints, holding patterns, error handlers for events such as loss of GPS or low battery, and changes of servo position, altitude and airspeed at waypoints. Autonomous takeoff and landing are supported, including bungee launch and hand launch. The control system provides gain scheduling, feed-forward terms for turns, and user-definable PID loops, for example for camera stabilisation. The GPS update rate is 1 Hz, with 4 Hz optional, and DGPS accuracy is supported.

For servo outputs the autopilot handles 8, 16 or 24 servos at 50 Hz with 11-bit resolution and an integrated RC override, with mixing for elevons, flaperons, V-tail, X-tail, split ailerons and split rudders. The airspeed sensor range is 500 kph and the altimeter range is 12,000 meters above the launch point. Additional ADC channels and a three-axis magnetometer are available. Onboard data logging stores flight data, and telemetry sends 100 user-defined fields at 5 Hz. The software can be upgraded in the field.

The MP2128g2 comes with the Horizon ground control software, which provides a point-and-click waypoint editor, in-flight changes to gains and waypoints, payload servo control and flight in RC mode through the data link, as well as an autopilot simulator for operator training. A configuration wizard and an installation video are included to shorten setup. Typical applications are small fixed-wing and other miniature unmanned aircraft used for surveying, surveillance and payload missions.