18. Introduction to Bluetooth

You must first complete 17. Data Logging before viewing this Lesson

Bluetooth uses radio frequencies to communicate between devices

The EV3 uses Bluetooth to download programs wirelessly

The EV3 also uses Bluetooth to connect to another EV3:
– Have them perform similar actions
– Synchronize their actions

Tips for Success

Give each brick an unique name (Sender and Receiver for this lesson)

Use an USB cable for downloading code to the bricks (rather than Bluetooth). You cannot connect between EV3s and a PC at the same time

Turn on the receiver robot first then the sender in the challenges in this lesson. This is because the challenge solution only sends the message once in Challenge 1.

18.1. Activating Bluetooth on the EV3

Turning on Bluetooth:

– On the EV3 menu, go to the symbol that looks like a wrench

– Go down to the word “Bluetooth” and activate it

To connect to another brick go back into the Bluetooth menu

– Go to “Connections”

– Select “Search” and find the other brick’s name

You can also manage your connections with the Bluetooth Connection Block.

18.2. Messaging Block

– The messaging block can be found in the Blue Pallet.
– You will also use the Wait For block in Messaging Mode

Challenge 1:

– Send a “Hello World” message from one brick to another
– The second brick should receive and display the message on its screen for 5 seconds

Hint: You will need to pair the two robots ahead of time. Name the robots by your team name (eg Hungary1) to ensure the uniqueness of the names. For this challenge, you will use the Messaging block -> Send -> Text. You will use the Wait For block in the Messaging Mode -> Change -> Text

Challenge 2: Synchronized Swimmers

– Move the first robot by hand and send the motors’ power to the other robot
– Have the second brick receive the data and copy the movement

Back to: Module 3. Programming