This is a simple project for running code on Lego Mindstorms EV3, using leJOS. The project contains a class with helper methods, EV3Helper, which may make it easier to use the device. It also contains a main class and some examples which utilizes the helper methods for some simple movement.
This project requires that you have Java Development Kit 7 installed on your system.
There exists a plugin for leJOS to Eclipse, which makes development easy. For convenience we are distributing Eclipse bundled with the Lejos EV3 plugin.
- Eclipse for Windows 64-bit
- Eclipse for Windows 32-bit
- Eclipse for OS X 64-bit
- Eclipse for OS X 32-bit
- Eclipse for Linux 64-bit
- Eclipse for Linux 32-bit
After launching Eclipse, you may have to set EV3_HOME, if it is not set. You
can do this by selecting Window -> Preferences -> leJOS EV3. Set EV3_HOME
to the leJOS_EV3_0.9.0-beta directory inside the eclipse directory you
unpacked.
To create a project select File -> New -> LeJOS EV3 Project. Uncheck Use default location and select the location you placed this project. Make sure
the selected JRE environment is JavaSE-1.7. Finally, press Finish.
After creating a leJOS-project, if the leJOS-libraries can't be found, right
click on your project and select leJOS EV3 -> Convert to leJOS EV3 project.
If you rather want to set up Eclipse with the leJOS-plugin yourself, you may follow the guide in README-ECLIPSE.md.
If you want to use IntelliJ, you may follow the guide in README-INTELLIJ.md.
If you want to build using Apache Ant instead of Eclipse, you may follow the guide in README-ANT.md.
To run a program, right click a file containing a main method, Run As -> LeJos EV3 Program.
When seeing the robot from the back, the rightmost motor should be connected to port A, and the left motor should be connected to port B. The wires do not have to cross.
The IR sensor should be connected to port 1, and the color sensor should be connected to port 4.
This is defined in src/no/itera/lego/EV3Helper.java, lines 65, 66, 73, 74, and can be changed.
Uncaught Exception: java.lang.UnsopprtedClassVersion. This means you are compiling for Java 8, which is not supported by leJOS. To solve this Right click project -> Properties -> Java Compiler -> Check "Enable project specific settings" -> change "Compiler compilance level" to 1.7.
Uncaught Exception: java.lang.IllegalArgumentException. Invalid sensor mode. Make sure all sensors are connected, and not in use by the EV3 Controller.
You can use system.out.println() to print to the display.
Press Center + Down at the same time to stop the current program.
You can start an uploaded program by Programs -> "name of program" -> Execute Program.
Make sure the color sensor is not too far or too close to the ground. Use the EV3 Control plugin in Eclipse to test the sensors. A color_ID to color chart can be found here.