CONNECTING THE ROBOT TO OPEN ROBERTA
How to connect Lego Mindstorms EV3 to Open Roberta
Download a PDF of the following
(IMPORTANT: If you are lending the EV3 robots from SEP, you will not need to do this procedure. Robots borrowed from SEP are already set up to run Open Roberta. Use this procedure only if you are purchasing your own EV3 robots, or using robots that already exist at your school site, and would like to use Open Roberta.)
Required Materials
- Device with an internet connection (iPad, Chromebook, laptop, desktop computer, etc.)
- WiFi dongle (1 per EV3 robot plugged into USB port)
- Recommended: Edimax EW-7811Un 150Mbps 11n Wi-Fi USB Adapter
- MicroSD card (1 per EV3 robot plugged into SD port)
- Recommended: SanDisk 4GB MicroSDHC Memory Card with SD Adapter
- An SD card reader that fits in your computer (most computers/laptops have a card reader built in on the side)
- WiFi router (one per classroom or set of robots)
Please note: EV3s will not connect to internet that require a login ID. The internet must require a password, but no login ID.
The following three-step procedure (preparing the micro SD card, installing Lejos, and connecting the EV3 to the WiFi) must be completed for each EV3 robot. If you are having trouble with any of the following steps, please contact Jessica Allen at [email protected].
Step 1: Preparing the micro SD Card
To connect the Lego Mindstorm EV3 to Open Roberta, you must first download a program called Lejos on each EV3. This is done by downloading Lejos onto a microSD card and creating what’s called a “bootable SD card.”
- Format your microSD cards to FAT32 (note: formatting on Macs may require an additional program download.)
- Put your micro SD card into the SD card adapter, then the adapter into the card reader of your computer. Connect the card reader to your computer.
- Click control “get info” to check the format (if the SD card is already FAT32, skip to the next step).
- Click format in the drop-down menu.
- Select “FAT32” as the file system and format.
- Add the Lejos files to the formatted microSD card to make a “bootable SD card.”
- Download the zip file from https://ucsf.box.com/s/uq3h7eslz5u9ez1sf5rs599ee7cozbxl
- Add all the files found inside the zip file to your micro SD card (you must unzip the folder before loading all the files onto your SD card. Do not unzip ejre-7u60-fcs-b19-linux-arm-sflt-headless-07_may_2014.gz).
- Check that the files on your micro SD card match those shown in the image.
- Safely remove the micro SD card adapter from your computer, then remove the micro SD card.
Step 2: Installing Lejos on the Lego Mindstorm EV3
Now that you have created a “bootable SD card”, insert this SD card into the Lego Mindstorms EV3. If you ever want to uninstall Lejos, simply remove the micro SD card and reboot the robot.
- Make sure that the EV3 robot is switched off.
- Insert the micro SD card into your EV3 (there is a port labeled SD on one side).
- If you plan to connect your robot using WiFi in Step 3, insert the WiFi USB adapter into the USB port.
- Start the EV3 robot by pressing the center dark gray button.
- The operating system will install automatically (about 8 minutes) and restart. You will hear a short melody when complete. The main menu should appear on the screen.
After installation, subsequent startups will be faster. Normally, the robot is ready within 1–2 minutes.
If you do not see the main menu screen, but instead see the standard Lego Mindstorms menu, the SD card is likely formatted incorrectly. Contact Jessica at [email protected] for help. See a video of the installation process here.
(To uninstall Lejos, remove the micro SD card. The robot will return to factory settings.)
Step 3: Connect your EV3 to the WiFi
We recommend maintaining a dedicated WiFi router for EV3s using Lejos and Open Roberta. This avoids needing to reset WiFi settings each time. The programming device does not need to be on the same network as the EV3.
Students should connect to Open Roberta using a firewalled school network, while EV3s connect via the dedicated router.
(Don’t have access to WiFi? See the links at the bottom of this page.)
- Set up your dedicated WiFi router with a password.
- Navigate to the WiFi menu on your EV3 robot (use left/right buttons).
- Select the WiFi menu using the center (Enter) button.
- Select your network using up/down buttons and press Enter.
- Enter the password using the on-screen keyboard.
- Use “U” for uppercase and “l” for lowercase
- Use “x” to delete the previous letter
- The bottom line shows entered characters
- Select “D” to confirm the password
- If successful, the EV3 will return to the main menu showing a second IP address and a WiFi icon in the top right.
Can’t connect via WiFi? Use USB instead:
Open Roberta USB App for Desktop (Windows, Linux, MacOS)