LibrePilot is
a
Free software
Free software, libre software, libreware sometimes known as freedom-respecting software is computer software distributed open-source license, under terms that allow users to run the software for any purpose as well as to study, change, distribut ...
unmanned aerial vehicle
An unmanned aerial vehicle (UAV) or unmanned aircraft system (UAS), commonly known as a drone, is an aircraft with no human pilot, crew, or passengers onboard, but rather is controlled remotely or is autonomous.De Gruyter Handbook of Dron ...
project for model aircraft aimed at supporting both multi-rotor craft as well as fixed-wing aircraft. Initially founded by David Ankers, Angus Peart and Vassilis Varveropoulos in late 2009, under the name OpenPilot, it was conceived as both a learning tool and to address areas the developers perceived were lacking in other small UAV platforms. In July 2015 OpenPilot, was
forked to create LibrePilot.
[
The OpenPilot open source autopilot software could be combined with hardware such as an ]inertial navigation system
An inertial navigation system (INS; also inertial guidance system, inertial instrument) is a navigation device that uses motion sensors (accelerometers), rotation sensors (gyroscopes) and a computer to continuously calculate by dead reckoning th ...
board, a main control board, a GPS receiver, and a 2.4 GHz serial communications link with the ground station.[
] The OpenPilot software is released under the GPL version 3 license.
Components
The OpenPilot project consisted of two component parts, these are the on-board firmware and the ground control station (GCS).[
] The firmware part of the project is written in C whilst the ground control station is written in C++ utilizing Qt.
Hardware
The current on-board hardware is based on the STM32 microcontroller
A microcontroller (MC, uC, or μC) or microcontroller unit (MCU) is a small computer on a single integrated circuit. A microcontroller contains one or more CPUs (processor cores) along with memory and programmable input/output peripherals. Pro ...
. There are two physical boards that are part of the hardware, the first is the main OpenPilot board which contains the core microcontroller
A microcontroller (MC, uC, or μC) or microcontroller unit (MCU) is a small computer on a single integrated circuit. A microcontroller contains one or more CPUs (processor cores) along with memory and programmable input/output peripherals. Pro ...
, SD socket, barometer plus servo connectors and second, the AHRS board which contains the sensor hardware. In other words, the hardware consists of two boards: the microcontroller board (the core) and the sensors board (the AHRS).
AHRS
The OpenPilot AHRS was a 9DOF unit and contains MEMS gyroscope
A gyroscope (from Ancient Greek γῦρος ''gŷros'', "round" and σκοπέω ''skopéō'', "to look") is a device used for measuring or maintaining Orientation (geometry), orientation and angular velocity. It is a spinning wheel or disc in ...
s, accelerometer
An accelerometer is a device that measures the proper acceleration of an object. Proper acceleration is the acceleration (the rate of change (mathematics), rate of change of velocity) of the object relative to an observer who is in free fall (tha ...
s and a 3 direction magnetometer. Combined with the sensors, the OpenPilot AHRS contains its own Cortex M3 microcontroller which runs a Kálmán filter.
See also
* Open-source robotics
* ArduCopter
* Paparazzi Project open-source autopilot
* PX4 autopilot
* Slugs (autopilot system)
References
{{Reflist
Avionics computers
Transport software
Open-source hardware
Unmanned aerial vehicles
Free software programmed in C
Free software programmed in C++
Software using the GNU General Public License