LeJOS is replacement firmware for the Lego Mindstorms RCX and NXT bricks. It’s based on the Java programming language and includes a JVM, or Java Virtual Machine, which allows Lego Mindstorms robots to be programmed in Java.

LeJOS is an open source project which means you can participate in its development, or download the source code and turn it into a creation of your own.

The current version is 0.85 released September 2009.

Lego Mindstorms Robotics Kits:

http://mindstorms.lego.com/

LeJOS Java for Lego Mindstorms

http://lejos.sourceforge.net/

Official LeJOS Developer Forum:

http://lejos.sourceforge.net/forum/

Lego Digital Designer:

http://ldd.lego.com/

Installing Lejos on Ubuntu 8.04 (old but still applicable):

http://lejos.sourceforge.net/forum/viewtopic.php?p=3785

http://ubuntuforums.org/showthread.php?t=854846

In 2008 at BCIT I worked with a team of 4 others in a software development project using LeJOS. BCIT owns a large room full (and I mean FULL) of Lego Mindstorms Lego. We applied what we had learned about iterative development and project management during our first year to a 5-week software development lifecycle, from requirements gathering to specification to implementation and delivery. We applied two terms of Java to a series of architecture and programming milestones and a final tournament based on the competitions organized by the First Lego League.

Our team (Hadaga) finished in 2nd place out of 23 (winner score: 495 / average score: 320 / our score: 395 ). I’ve included some of our code and design documents as an example of great teamwork and good clean fun.

Our Team Hadaga Tournament Code (Uncompiled Java):

Nano table [3 KB] Power table [12 KB]

Team Hadaga Robot Building Instructions (Lego Digital Designer format):

Hadaga_Building_Instructions.lxf [28 KB]

Team Hadaga Design Docs (pdf):

Team Agreement [73 KB] Concept Document [224 KB] Design Document [3.4 MB]