Use mBot with App Inventor

Notice:

A new version (V1.9) has been released! It’s easier to use, especially in environments with multiple robots. Take a look now.

MIT App Inventor is a drag-and-drop block-based editor which can make Android Apps. You can use App Inventor to control mBots through an extension.

Add the mBot extension to App Inventor

You need an App Inventor website that supports extensions. One example is http://extension-test.appinventor.mit.edu/. Login and start a new project.

In the “Extension” group of the left panel, click “Import Extension” link, then select “URL”. Paste the following linke to the text box:

http://appinventor.makeblock.com/com.makeblock.appinventor.MBot.aix

Then click “import”.

In the next screen, click “OK”. Then You will find a new “mBot” component in the “Extension” group:

Connect to your mBot through a ListPicker

Drag a ListPicker component to the canvas, and add a mBot component (it is a non-visible component, won’t shown up in the phone screen but will be at the bottom of the phone screen):

Write a program like the following picture using blocks from ListPicker and mBot. When run, this will create a list of paired mBot robots (you need to link the mBot with the Android system’s Bluetooth setting screen at first use), and allow users to select and connect to one of the robot.

Write Programs with App Inventor

When connected, you can control mBot and read from its sensors with any of blocks provided by the mBot extension. The following program is an example:

Here is a list of blocks you can use to write your program:

	Make the robot move forward at a certain speed (number of 0-255)
	Make the robot move backward at a certain speed (number of 0-255)
	Make the robot turn left at a certain speed (number of 0-255)
	Make the robot turn right at a certain speed (number of 0-255)
	set the speed of both motors (0-255) of the connected mBot. This is for advanced control
	Make the mBot stop moving
	light up the mBot’s on-board RGD LEDs with a certain color. “whichLight” field accept a number: (0: both lights, 1: right light, 2- left light).
	Play a musical note using the internal buzzer of mBot. duration is in milliseconds, and frequency is for the pitch.
	read the value of the lightness sensor.
	read the value of the ultrasonic sensor. Usually connected to port 3.
	read the value of the temperature sensor (in Celsius degrees).
	read the value of the humidity sensor (in percentage).
	get a list of available mBot robots. Used in Bluetooth connection
	connect to a mBot with the certain address, usually an item from the “availableRobots” list.