3D Robotics

ArduPilot (Legacy) main page




[This original ArduPilot board, now called the "Legacy ArduPilot" is no longer produced or officially supported by the DIY Drones dev team, and this page is maintained just for historic reasons. However, there are still many users of it out there and it still works fine. The user group for Legacy ArduPilot users, for both thermopile and IMU use, is here.]


ArduPilot is a full-featured autopilot based on the Arduino open-source hardware platform. It uses infrared (thermopile) sensors or an IMU for stabilization and GPS for navigation. It is the autopilot used to win the 2009 Sparkfun Autonomous Vehicle Competition.

The hardware is available from Sparkfun for $24.95. An expansion board ("Shield") kits that includes an airspeed sensor, a 3.3v power regulator for 3.3v GPS modules and other sensors and cables and connectors for easy attachment of the XY and Z sensors, is available from our own store for $57.20.


User f

ArduPilot features include:

  • Can be used for an autonomous aircraft, car or boat.
  • Built-in hardware failsafe that uses a separate circuit (multiplexer chip and ATTiny processor) to transfer control from the RC system to the autopilot and back again. Includes ability to reboot the main processor in mid-flight.
  • Multiple 3D waypoints (limited only by memory)
  • Altitude controlled with the elevator and throttle
  • Comes with a 6-pin GPS connector for the 4Hz uBlox5 or 1hz EM406 GPS modules.
  • Has six spare analog inputs (with ADC on each) and six spare digital input/outputs to add additional sensors
  • Supports addition of wireless modules for real-time telemetry
  • Based on a 16MhZ Atmega328 processor. Total onboard processing power aprox 24 MIPS.
  • Very small: 30mm x 47mm
  • Can be powered by either the RC receiver or a separate battery
  • Four RC-in channels (plus the autopilot on/off channel) can be processed by the autopilot. Autopilot can also control four channels out.
  • LEDs for power, failsafe (on/off), status and GPS (satellite lock).


ArduPilot requires the free Arduino IDE to edit and upload the code to the ArduPilot board.

The code is currently optimized for the Mutiplex EasyStar three-channel powered glider and FMA sensors, but can be modified for other aircraft and sensors. It uses the rudder/ailerons and elevator to maintain level flight and navigate to GPS waypoints. It supports a desktop setup utility and ground station software. It also includes a "fly-by-wire" mode that simply stabilizes RC flight. The main code is ArduPilot2.x.zip in the download section of our Google Code repository, where x is the latest version.

What you need to make a fully-functional autopilot:

Open source extras:

  • If you want to build your own board from scratch, the necessary files and component lists are here.
  • [Note: you shouldn't need this, since this code is loaded on the ArduPilot board at the factory] Latest multiplexer code (for the board's second processor, an Attiny, which runs the failsafe system) is here.
    Instructions for loading this code are here.

Recommended UAV setup:


Airframe option one: Hobbico SuperStar (49" wingspan, $95, shown above). This is an inexpensive, good flying high-wing trainer with ailerons. It can be hand launched in a park or take off from a runway, and replacement parts are readily available in case of a crash. If you want much better performance with this aircraft, you can upgrade it to a brushless motor, speed controller and a LiPo battery. [If you don't already have one, you'll also need a balancing charger and power supply.] Note: any stable aircraft with both ailerons (for stabilization) and rudder (for navigation) can work, so feel free to experiment with what you've got.


Airframe option two (recommended for ArduPilot 2.x): EasyStar (shown above). Performance can be improved with the modifications described in this post.

You'll also need:

  • A six or seven channel RC transmitter and receiver, with at least one toggle switch (ideally three-position but two-position will work, too, although you will have to mix channels to have access to both autopilot modes in the air), such as the Futaba 7C.
  • Some servos (at least three for ArduPilot 1.0; at least two for ArduPilot 2.x) and at least three female-to-female servo cables to connect the RC receiver to ArduPilot.

Cool optional extras for your UAV:

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  • Wow, what a dick move.  The manual for the original is no longer available.

  • can it be also configured for quadcopter or not ?

  • Moderator
    Wilmir, I use arduino use 0022. The pins should be marked on your board indicating where the black and or green pins are. Two pins on the board are not used on the cable so just line up the pin wire and you are good (black to black I believe).
    This page in the paragraph under the pic of the ardupilot board is a link to the Ardupilot (legacy) group, click that link to get more details.
  • Hi,

    I am a student in a high school and am trying to build a UAV copter for technology class. I have an Arduino v1.1 (Legacy) and I have 2 problems:

    My first problem is that I don't know what version of IDE I should use and which board from the list to select.

    The second problem is that I am not sure how to connect the FTDI cable. Mine has 6 pins (GND,CTS,VCC,TXD,RXD,DTR) and the side connector in Ardupilot has 8 pins with different names.

    Thank you very much for your help.


  • Hi all, Is it possible to modify the code and/or change the mission or load a new code load a new mission once it has been loaded to the board?

  • Hi,

    Ì am trying to tune my Ardupilot but it seems hard to do it successfully.

    When i switch to stabilize for fine tuning the servos respond correctly but are constantly jitering.

    I use:

    Easyglider Pro

    Ardupilot with blue Shield

    RangeVideo XY and Z sensors and


    Any idea?


  • 3D Robotics
    Brian, we don't support that early hardware anymore. I think the easiest option would be for me to send you the more recent ArduPilot hardware at a "friends and family" discount. Please PM me and we can work through the details.
  • Moderator

    I've combed the manual online and followed it, although it's for the most current board with the Adrushield v2, my setup is the original ArduPilot w/the atmega168 and the ArduShield v1.  I'm trying to determine what is the latest code I can run, which I believe is ArduPilot_24, everything above that says not enough room when trying to upload. 

    With 22, 23, 24 I get the following error:

    55: error: easystar.h: No such file or directory In function 'void navigation()':

    I have confirmed the file is included in the folder, but I don't know what I'm missing on making the program know the file is there. 


  • 3D Robotics
    The bind plug is no longer used. The reset button just lets you reset the board, which is handy. Please just follow the current manual.
  • Hello, I am having a hard time building the ArduPilot Shield expansion board kit. I need more information about the "bind plug" i see that it has something to do with the throttle but i am still confused. I would like to be able to control the throttle manually and with autopilot. I also am confused with the "reset button" what are the benefits of installing the "reset button?" I am building the EasyStar. 



    Matthew Waymack

This reply was deleted.