EV3Dev-lang-Java is a Java project designed to build Software for Robots with EV3Dev hardware & the LeJOS way.

What is the latest EV3Dev version supported?

The libraries was tested with the latest stable EV3Dev release: Debian Jessie

• Note: In the next release, we will include support for Debian Stretch

What is the hardware platforms supported in this project?

This Debian distro run nice with the following platforms:

• EV3 Brick: 4.4.47-19-ev3dev-ev3
• RaspberryPi 3 with BrickPi3 & PiStorms: 4.4.47-19-ev3dev-rpi2

If you need further information about stable EV3Dev images, click here

• Note: In the next release, we will include support for Raspberry Pi 3 Model B+

In Lego Mindstorms ecosystem, the default solution to develop Java software for Lego Mindstorms is LeJOS. But now exists one alternative, EV3Dev-lang-java a Java project running on the top of EV3Dev.

Lego Mindstorms ecosystem is a nice educational way to learn Java programming in general and Robotics in particular. Now, it is possible to install a complete Linux distro in the third generation of the product and others companies like Mindsensors & Dexter Industries has released products which interact with Sensors & Actuators from Lego ecosystem and that boards can use the Power of the popular board Raspberry Pi 3

But, with the help of EV3Dev, it is possible to have the same Linux experience for multiple boards. So... why not develop a Java library for that Linux Distro? The answer is EV3Dev-lang-java. The project, takes the good things of both worlds: EV3Dev with the complete linux experience and LeJOS with the rich local navigation stack.

What projects are developed in EV3Dev-lang-java?

The following list contains the stables projects that it is possible to use without any restriction:

• EV3Dev-lang-java: Low level interation with EV3Dev
• lejos-commons: LeJOS interfaces & utilities
• lejos-navigation: LeJOS navigation stack
• RPLidar4J: RPLidar A1 support
• Battery Monitor: A battery monitor to protect your hardware against low battery levels
• Installer: A set of Bash scripts to automate some operations with your brick
• Template project: A Gradle project ready to test the project
• Examples: A repository with several examples about the usage of this project

Incubator projects:

• OpenJDK for EV3: A custom OpenJDK JRE build for EV3
• Usb Devices: A library to use Arduino, Grove Sensors, GPS, IMU, LIDAR, and more devices...
• ROS: A library to publish Sensor data to ROS for SLAM purposes

Advantages of the usage of this project?

Using this library you can develop educational robots with Java for multiple Bricks:

• EV3 Brick
• BrickPi+
• BrickPi 3
• PiStorms

Using the same objects, it is possible to deploy the software for robots on EV3 Brick, Raspberry Pi 3 with BrickPi 3 & PiStorms.

If you analyze the hardware, any EV3 Brick uses a SoC: Sitara Processor AM1808 (from year 2010) to manage Sensors & Actuators but now with the usage of a BrickPi/PiStorms unit, it is possible to use the power of a Raspberry Pi 3 increasing the possibilities to develop complex projects which require por Computational consumption.

2010 Chip included on EV3 Brick:

SoC: Sitara Processor AM1808
CPU: ARM9 300MHz
RAM: 16KB of Instruction Cache, 16KB of Data Cache ,8KB of RAM (Vector Table), 64KB of ROM

2018 Chip included on Raspberry Pi 3 Model B+:

SoC: Broadcom BCM2837 RISC de 64 bits
CPU: 4× ARM Cortex-A53, 1.4GHz
RAM: 1GB LPDDR2 (900 MHz)

Java features

• Automatic installation of Oracle Java JDK 8 for Brickpi+/PiStorms + Raspberry Pi 3
• Partial installation of Oracle Java JRE 8 for EV3 Brick
• OpenJDK Java 9 EA support for Brickpi+/PiStorms + Raspberry Pi 3
• Java profiling tools Support (Oracle mission control & JConsole)
• Logging support based on SLF4J
• Centralized logs with Kibana

Platform features

• Support for EV3 Brick, PiStorms v1/v2, BrickPi+ & BrickPi 3

Lego Mindstorms features

• Regulated Motor Support
• Unregulated Motor Support
• Sensor Support (EV3 sensors)
• Sounds Support
• EV3 LCD Support

Robotics

• Automatic installation of OpenCV
• eSpeak TTS (Text to speech) Support
• LeJOS Sensor filter Support
• LeJOS local navigation stack Support
• RPLidar A1 (2D Lidar) Support

Review the backlog to follow the features in course: https://github.com/ev3dev-lang-java/ev3dev-lang-java/issues

Take a look the documentation to use the project:

http://ev3dev-lang-java.github.io/docs/support/index.html

Take a look the following repository to learn how to use this project:

https://github.com/ev3dev-lang-java/examples

It is very easy to copy one example and use inside of the project template:

https://github.com/ev3dev-lang-java/template_project_gradle

• https://www.youtube.com/watch?v=Gxew3aNH6ks
• https://www.youtube.com/watch?v=1d9q24aNMHQ
• https://www.youtube.com/watch?v=SIwG848ODI8

Exist many examples used to test the project. In the future we will automate a good % of the tests using JUnit testing and Mocks but at the moment, many features are tested manually.

• LeJOS: http://www.lejos.org/
• LeJOS Git: http://sourceforge.net/p/lejos/ev3/code/ci/master/tree/
• LeJOS Forum: https://lejos.sourceforge.io/forum/search.php?keywords=ev3dev&sid=8642d9d1b361bcfdcdeabb26db89e632
• EV3Dev: http://www.ev3dev.org/
• EV3Dev // Getting Started: http://www.ev3dev.org/docs/getting-started/
• EVEDev // Linux Kernel Drivers: http://docs.ev3dev.org/projects/lego-linux-drivers/en/ev3dev-jessie/
• Dexter Forum: http://forum.dexterindustries.com/search?q=java