1. Before you build the project for the first time, you'll need to run make configure from a sketch directory (i.e. ArduPlane, ArduCopter, etc...). This will create a config.mk file at the top level of the repository. You can set some defaults in config.mk

2. In the sketch directory, type make to build for APM2. Alternatively, make apm1 will build for the APM1 and make px4 will build for the PX4. The binaries will generated in /tmp/<i>sketchname</i>.build.

3. Type make upload to upload. You may need to set the correct default serial port in your config.mk.

ardupilot has a standardized Linux virtual machine (VM) setup script that uses the free VirtualBox virtualization software. You can use it to create a standard, reproducible development environment in just a few minutes in Linux, OS X, or Windows.

1. Download VirtualBox for your Mac, Windows or Linux machine.

2. Install vagrant.

3. In the ardupilot directory, run vagrant up from the command line. This will create a new Ubuntu Linux VM.

4. Run vagrant ssh -c "ardupilot/Tools/scripts/install-prereqs-ubuntu.sh -y". This will install all the prerequisites for doing ardupilot development.

You can now run vagrant ssh to log in to the development environment. The ~/ardupilot directory in the VM is actually the ardupilot directory in your host operating system--changes in either directory show up in the other.

Once you've followed the instructions above, here's how you would build ArduCopter for PX4 in the development environment:

$ vagrant ssh
# cd ardupilot/ArduCopter
# make configure

Back at the terminal:

# make px4
# make px4-upload  # (optional)

ArduPilot users should use the DIYDrones.com forums for technical support.

The ArduPilot project is open source and maintained by a team of volunteers.

To contribute, you can send a pull request on Github. You can also join the development discussion on Google Groups. Note that the Google Groups mailing lists are NOT for user tech support, and are moderated for new users to prevent off-topic discussion.