ArduPilot


ArduPilot is an autopilot software program that can control multirotor drones, fixed-wing and VTOL aircraft, RC helicopters, ROVs, ground rovers, boats, submarines, uncrewed surface vessels, AntennaTrackers and blimps. It is published as open source software under the GNU GPL version 3.
ArduPilot was originally developed by hobbyists to control model aircraft and rovers and has evolved into a full-featured and reliable autopilot used by industry, research organisations, amateurs, and militaries.

Characteristics

The ArduPilot software suite consists of navigation software running on the vehicle, along with ground station controlling software including Mission Planner, APM Planner, QGroundControl, MavProxy, Tower and others.

Common to all vehicles

ArduPilot provides a large set of features, including the following common for all vehicles:
  • Fully autonomous, semi-autonomous and fully manual flight modes, programmable missions with 3D waypoints, optional geofencing.
  • Stabilization options to negate the need for a third party co-pilot.
  • Simulation with a variety of simulators, including ArduPilot Software in the Loop Simulator.
  • Large number of navigation sensors supported, including several models of RTK GPSs, traditional L1 GPSs, barometers, magnetometers, laser and sonar rangefinders, optical flow, ADS-B transponder, infrared, airspeed, sensors, and computer vision/motion capture devices.
  • Sensor communication via SPI, I²C, CAN Bus, Serial communication, SMBus.
  • Failsafes for loss of radio contact, GPS and breaching a predefined boundary, minimum battery power level.
  • Support for navigation in GPS denied environments, with vision-based positioning, optical flow, SLAM, Ultra Wide Band positioning.
  • Support for actuators such as parachutes and magnetic grippers.
  • Support for brushless and brushed motors.
  • Photographic and video gimbal support and integration.
  • Integration and communication with powerful secondary, or "companion", computers
  • Rich documentation through ArduPilot wiki.
  • Support and discussion through ArduPilot discourse forum, Gitter chat channels, GitHub, Facebook.

    Copter-specific

  • Flight modes: Stabilize, Alt Hold, Loiter, RTL, Auto, Acro, AutoTune, Brake, Circle, Drift, Guided,, Land, PosHold, Sport, Throw, Follow Me, Simple, Super Simple, Avoid_ADSB.
  • Auto-tuning
  • Wide variety of frame types supported, including tricopters, quadcopters, hexacopters, flat and co-axial octocopters, and custom motor configurations
  • Support for traditional electric and gas helicopters, mono copters, tandem helicopters.

    Plane-specific

  • Fly By Wire modes, loiter, auto, acrobatic modes.
  • Take-off options: Hand launch, bungee, catapult, vertical transition.
  • Landing options: Adjustable glide slope, helical, reverse thrust, net, vertical transition.
  • Auto-tuning, simulation with JSBSIM, X-Plane and RealFlight simulators.
  • Support for a large variety of VTOL architectures: Quadplanes, Tilt wings, tilt rotors, tail sitters, ornithopters.
  • Optimization of 3 or 4 channel airplanes.

    Rover-specific

  • Manual, Learning, Auto, Steering, Hold and Guided operational modes.
  • Support for wheeled and track architectures.

    Submarine-specific

  • Depth hold: Using pressure-based depth sensors, submarines can maintain depth within a few centimeters.
  • Light Control: Control of subsea lighting through the controller.
ArduPilot is fully documented within its wiki, totaling the equivalent of about 700 printed pages and divided in six top sections: The Copter, Plane, Rover, and Submarine vehicle related subsections are aimed at users. A "developer" subsection for advanced uses is aimed primarily at software and hardware engineers, and a "common" section regrouping information common to all vehicle types is shared within the first four sections.

Supported hardware

Copter, Plane, Rover, AntennaTracker, or Sub software runs on a wide variety of embedded hardware, typically consisting of one or more microcontroller or microprocessor connected to peripheral sensors used for navigation. These sensors include MEMS gyroscopes and accelerometers at a minimum, necessary for multirotor flight and plane stabilization. Sensors usually include, in addition, one or more compass, altimeter and GPS, along with optional additional sensors such as optical flow sensors, airspeed indicators, laser or sonar altimeters or rangefinders, monocular, stereoscopic or RGB-D cameras. Sensors may be on the same electronic board, or external.
Ground Station software, used for programming or monitoring vehicle operation, is available for Windows, Linux, macOS, iOS, and Android.
ArduPilot runs on a wide variety of hardware platforms, including the following, listed in alphabetical order:
  • Intel Aero
  • APM 2.X, designed by Jordi Munoz in 2010. APM, for ArduPilotMega, only runs on older versions of ArduPilot.
  • BeagleBone Blue and PXF Mini.
  • , formerly called Pixhawk 2,, designed by ProfiCNC in 2015.
  • , drone controller with video streaming system, designed by Emlid.
  • , designed by Erle Robotics.
  • Intel Minnowboard.
  • by Blue Robotics
  • and Navio+, designed by .
  • Parrot Bebop, and Parrot C.H.U.C.K., designed by Parrot, S.A.
  • Pixhawk,, originally designed by Lorenz Meier and ETH Zurich, improved and launched in 2013 by PX4, 3DRobotics, and the ArduPilot development team.
  • PixRacer, designed by AUAV.
  • Qualcomm SnapDragon.
  • Virtual Robotics VRBrain.
  • Xilinx SoC Zynq processor.
In addition to the above base navigation platforms, ArduPilot supports integration and communication with on-vehicle companion, or auxiliary computers for advanced navigation requiring more powerful processing. These include Nvidia TX1 and TX2, Intel Edison and Intel Joule, HardKernel ODROID, and Raspberry Pi computers.

History

Early years, 2007–2012

The ArduPilot project earliest roots date back to late 2007 when Jordi Munoz, who later co-founded 3DRobotics with Chris Anderson, wrote an Arduino program to stabilize an RC Helicopter. In 2009 Munoz and Anderson released Ardupilot 1.0 along with a hardware board it could run on. That same year Munoz, who had built a traditional RC helicopter UAV able to fly autonomously, won the first Sparkfun AVC competition. The project grew further thanks to many members of the DIY Drones community, including Chris Anderson who championed the project and had founded the forum based community earlier in 2007.
The first ArduPilot version supported only fixed-wing aircraft and was based on a thermopile sensor, which relies on determining the location of the horizon relative to the aircraft by measuring the difference in temperature between the sky and the ground. Later, the system was improved to replace thermopiles with an Inertial Measurement Unit using a combination of accelerometers, gyroscopes and magnetometers. Vehicle support was later expanded to other vehicle types which led to the Copter, Plane, Rover, and Submarine subprojects.
The years 2011 and 2012 witnessed an explosive growth in the autopilot functionality and codebase size, thanks in large part to new participation from Andrew "Tridge" Tridgell and HAL author Pat Hickey. Tridge's contributions included automatic testing and simulation capabilities for Ardupilot, along with PyMavlink and Mavproxy. Hickey was instrumental in bringing the library to the code base. The HAL greatly simplified and modularized the code base by introducing and confining low-level hardware implementation specifics to a separate hardware library.
2012 also saw Randy Mackay taking the role of lead maintainer of Copter, after a request from former maintainer Jason Short, and Tridge taking over the role of lead Plane maintainer, after Doug Weibel who went on to earn a Ph.D. in Aerospace Engineering. Both Randy and Tridge are current lead maintainers to date.
The free software approach to ArduPilot code development is similar to that of the Linux Operating system and the GNU Project, and the PX4/Pixhawk and Paparazzi Project, where low cost and availability enabled hobbyists to build autonomous small remotely piloted aircraft, such as micro air vehicles and miniature UAVs. The drone industry, similarly, progressively leveraged ArduPilot code to build professional, high-end autonomous vehicles.

Maturity, 2013–2016

While early versions of ArduPilot used the APM flight controller, an AVR CPU running the Arduino open-source programming language, later years witnessed a significant re-write of the code base in C++ with many supporting utilities written in Python.
Between 2013 and 2014 ArduPilot evolved to run on a range of hardware platforms and operating system beyond the original Arduino Atmel based microcontroller architecture, first with the commercial introduction of the Pixhawk hardware flight controller, a collaborative effort between PX4, 3DRobotics and the ArduPilot development team, and later to the Parrot's Bebop2 and the Linux-based flight controllers like Raspberry Pi based NAVIO2 and BeagleBone based ErleBrain. A key event within this time period included the first flight of a plane under Linux in mid 2014.
Late 2014 saw the formation of DroneCode, formed to bring together the leading open source UAV software projects, and most notably to solidify the relationship and collaboration of the ArduPilot and the PX4 projects. ArduPilot's involvement with DroneCode ended in September 2016. 2015 was also a banner year for 3DRobotics, a heavy sponsor of ArduPilot development, with its introduction of the Solo quadcopter, an off the shelf quadcopter running ArduPilot. Solo's commercial success, however, was not to be.
Fall of 2015 again saw a key event in the history of the autopilot, with a swarm of 50 planes running ArduPilot simultaneously flown at the Advanced Robotic Systems Engineering Laboratory team at the Naval Postgraduate School.
Within this time period, ArduPilot's code base was significantly refactored, to the point where it ceased to bear any similarity to its early Arduino years.