Crazyflie Java library

The intention of this library is to be the Java equivalent of crazyflie-lib-python, a Python based library that is used by the Crazyflie Python client.

Therefore this library is heavily based on the Python implementation. Some components are almost identical, some differ more to accommodate different programming concepts in Python and Java.

Over time the Java library will be adapted to make use of Java specific features like Lambda expressions, etc.

This library should make it easy to implement Java based clients for the Crazyflie, for example on Android or as a Eclipse RCP application.

Features

• Abstract USB interface that allows to use different USB implementations, eg. pure Java and Android

Installation

It can be installed in Eclipse from the P2 update site:

https://fredg02.github.io/se.bitcraze.crazyflie.lib/p2

Integration

The Crazyflie Java library is a Tycho project.

Since it uses some non-OSGi dependencies it requires some workarounds to be build:

1. Change directory to se.bitcraze.crazyflie.lib-parent
2. Generate a target platform P2 repository which contains the dependencies required for the build:

   mvn clean verify -f ../se.bitcraze.crazyflie.lib-target/pom.xml
   

3. Fix the path to the target platform P2 repository

   ./fixTargetDefinition.sh
   

   or

   ant -f fixTargetDefinition.xml
   

4. Run normal Maven build

   mvn clean verify
   

Please note: steps 1-3 only have to be run once.

After the Maven build is completed a compiled JAR can be found in the se.bitcraze.crazyflie.lib/target directory, e.g. se.bitcraze.crazyflie.lib-0.0.1-SNAPSHOT.jar.

The Tycho build also generates a P2 repository that can be used for Eclipse Plug-in based projects. It can be found in the se.bitcraze.crazyflie.lib-repository/target directory, e.g. se.bitcraze.crazyflie.lib-repository-0.0.1-SNAPSHOT.zip.

Dependencies

• usb4java
• Jackson
• SLF4J
• JUnit

Tests

JUnit tests can be executed from the command line with:

mvn clean verify

Or from within Eclipse by running /se.bitcraze.crazyflie.lib/src/test/java/se/bitcraze/crazyflie/lib/AllTests.java as a JUnit test.

Please make sure that a Crazyradio (PA) is connected and a Crazyflie 1.0 or 2.0 is switched on, when running the tests (otherwise they will fail).

Examples

Examples are included in the se.bitcraze.crazyflie.lib.examples directory.

Known issues

• Bootloader not fully supported yet
• Debug driver incomplete (Tests currently need Crazyflie/Crazyradio to run successfully)
• Too many Thread.sleep()s ;)