When I compile the ev3tools from the lejos-ev3 0.5.0-alpha release in Eclipse I get a bizarre error saying that the Java class loader cannot find the class file. Here is how I fixed that problem.
Programming
Using the Mindsensors EV3 Console Adapter on Mac OS
Mindsensors have released a special EV3 Console Adapter that lets you connect your EV3 console to a PC or Linux. What’s missing so far is a Mac OS X driver, so in this tutorial I show you how to configure the standard FTDI driver to work with the Mindsensors EV3 Console Adapater. Why do you(…)
HelloWorld.java: first steps with Java on EV3
In my last post I shared how to get a working version of leJOS running on your wifi-enabled EV3. Now we need to make it do something, so in this tutorial I will cover the basic tools for compiling, uploading and executing leJOS Java programs on the EV3. Get the leJOS source Andy has uploaded(…)
Java on the EV3; porting leJOS
Now you can experiment with a very early port of leJOS to the EV3 courtesy of Andy Shaw, one of the core developers of the leJOS framework. If you prefer coding in Java and enjoy the rich class library support offered by leJOS then this post is for you! But be warned; it’s early days(…)
SoundMachine - building music with LEGO bricks
SoundMachine is a LEGO drum sequencer that “builds” music using standard LEGO bricks. SoundMachine is an interactive music tool to collaboratively develop music. SoundMachine scans 2×2 colour LEGO bricks arranged in 4 tracks of 8 beats. The colour information is converted to MIDI messages by a Processing sketch, which sends MIDI to Ableton Live to(…)
NXTified 9398 Rock Crawler with wifi control
The new LEGO 9398 RockCrawler is out, and I really enjoyed how the designers chose to mount the motors directly on the pendular axles. Looking at it I realised that by replacing the power-function motors with NXT motors I could make the RockCrawler driven by the NXT. I had a new NXT2WIFI sensor from Dani(…)
Teaching Java programming using leJOS and Mindstorms
leJOS is also well suited to teaching the basic principles of object-oriented programming; it is Java after all! And what better way to illustrate in concrete terms how powerful Java is than by applying it to building robots?
Updated: a leJOS driver class for the NXT2WIFI
Danny Benedettelli recently provided me with a NXT2WIFI prototype sensor to start development of a leJOS driver for it. I’ve been working on the code in my (limited) spare time and have a basic client and server interface developed in Java. This is available in the latest SVN snapshot of leJOS.
leJOS Clases to communicate with the NXTBee in Java
This project presents a leJOS class to interface with the NXTBee, along with some sample Java code in leJOS showing how to send and receive data. I’ve written extensively about the Dexter Industries NXTBee sensor before. The NXTBee provides long-range serial wireless communication for the Lego Mindstorms NXT.
Live plotting map data from the dGPS using Processing
I wanted to draw a live map showing the progress of the Lego Street View car as it drove outside. The dGPS sensor does a great job of plotting the car’s location, and the NXTBee provides a perfect high-speed long-distance serial link back to my Mac at home base. But how to display a live map that is updated with the(…)