Some setup steps are necessary to program your LEGO Mindstorms EV3 robot by using the Open Roberta Lab.We tried to describe the setup steps as easy as possible. If you have difficulties with some instructions then you first should refer to our FAQ. If your question is not present in the FAQ just write an e-mail to us.
If all components listed are available the setup procedure for the EV3 will take about 30 minutes. First check whether you have all components available, and then follow steps 1-4.
Components for Open Roberta®:
A computer, connected to the internet.
- An empty Micro SD card, minimum 4 GB, less than 32 GB of memory
- A SD card reader fitting to your computer. Many computers have an integrated SD card reader.
At first the operation system EV3DEV for the EV3 robot will be installed.
Step 1: The operation system EV3dev for Open Roberta
The EV3 Roboter needs a special operation system to be prepared for programming with the Open Roberta Lab. The operating system EV3dev will be copied to a micro SD card. The EV3 robot can automatically start from a micro SD card, similar to a PC starting from a CD ROM or from an USB stick. The original LEGO firmware in your EV3 brick will not be changed. Running the EV3 brick without the micro SD card will run the original LEGO system.
First download the EV3dev operating system for your EV3 robot by following this link: LEGO Mindstorms EV3 - Download for EV3
Step 2: Set up the micro SD card
Put an empty micro SD card into the adapter of your computer.
- Use some image writing software to transfer the EV3dev operating system to the SD card. A simple tool is available here: ETCHER
- Start the software to write the operating system image to the micro SD card (the following pictures show ETCHER).
- Select as source file (Select Image) the previously downloaded file:
ev3dev-jessie-ev3-generic-2017-02-11.zip (maybe the date will look different).
Wait for a short time (up to half a minute) until the selection is shown in the software window.
- As destination drive select the micro SD. Normally ETCHER finds the correct drive (see picture above). If the drive selected is not correct you may change this by clicking on "Change".
If you have not yet inserted a micro SD card you will be prompted to do so. (Connect a drive; see picture below).
Click "Flash". The image transfer starts. Image transfer and check will last about 10 minutes.
After the successful transfer of EV3dev you see this message:
Finally you quit the transfer program and take out the micro SD card from your computer.
Step 3: Installing the EV3dev system on the micro SD card
The new operating system is available on the micro SD card. With the first start of the EV3 robot the installation will uniquely installed. This procedure works automatically. Follow these steps:
- Be sure that the EV3 robot is switshed off.
- Insert the micro SD card into the EV3 robot.
- Insert the WiFi USB dongle into the USB socket of your EV3 robot.
- Start your EV3 robot.
- The operation system EV3dev installs and starts automatically within some minutes. The installation is completed when the main menu is shown on the EV3 display.
The installation procedure takes some minutes – in the meantime maybe you like to visit the Open Roberta Lab.
After the operating system once is installed your EV3 robot will start much quicker. On the average the EV3 is available 1-2 minutes after switching on.
Step 4: WiFi Connection
The following instructions will show you how to connect your robot to a WiFi network.
- Plug in the WiFi dongle into the USB port of the EV3 robot and switch on the robot.
- Navigate to the entry Wireless and Networks and push the enter button of the robot.
- Select Wi-Fi and push the enter button.
- The display shows Powered, quit this by pushing the enter button.
- Select Start Scan and push the enter button to find all available WiFi networks.
- Choos your WiFi network and click Connect.
- Now comes the most tricky part. Enter the WiFi password by using the display keyboard on your EV3 brick. The characters and character categories will be selected by using the up, down, left, and right buttons on your EV3 brick. Pressing the enter button will accept the selected character or character category.
- When the password is complete you click Accept.
- The last message will show the password again. This has to be confirmed with Accept again.
If everything worked fine the received IP address will be shown in the upper left corner of the EV3 display.
Once connected - immediately available
Once you have established a WiFi connection the EV3 robot remembers this connection. After switching off and on the robot will automatically connect to the WiFi used last time.
If it does not work ...
If this step did not work maybe the password was wrong. Just try again.
Step 5: Set up the EV3 for the Open Roberta Lab
Use a computer with WiFi component and installed putty. If you do not have putty you may download and install it: Putty.
- Connect your compute to the WiFi network in which the EV3 robot is logged in.
- Start Putty.
- Use Putty to establish a SSH connection to the EV3 roboter.
Confirm a security warning of Putty by clicking Yes.
- Use the following data to login with Putty: robot / maker
- In the dialog windows of Putty enter the following commands on after the other. If you get a request enter the password again.
sudo systemctl unmask openrobertalab.service
sudo systemctl start openrobertalab.service
- Quit Putty by closing the Putty window.
- Well done: The installation of the EV3dev operating systems is finished. In the fist line of the EV3 display you recognize the Roberta eyes. The eyes are closed as long as there is no connection established to the Open Roberta Lab.
Once connected - immediately available
Once you have installed the EV3dev operating system the robot remembers this installation. After switching off and on the robot just wait until the Roberta eyes are visible. Then your EV3 robot is operational.
EV3 Robot configuration
We have modelled the EV3-Brick in the EV3 Robot Configuration menu. It is important to declare which motors and sensors are connected to the robot. It is also important to define the types of motors and sensors (e.g. large motor or color sensor), and the connection ports have to be correctly assigned (1 to 4 for the sensors and A to D for the motors) on your robot. The program will only be executed correctly if the robot configuration is defined exactly as your robot is constructed. If the robot construction & configuration does not match the program created, then the robot either will do nothing or it will throw an error.
Wheel diameter and track width
The wheel diameter and track width (the distance between the middle of the left and the middle of the right wheel) has to be assigned. This is important, because if you are using blocks from the Action category the distance parameter for the calculation of how much the robot has moved is based on this assignment.