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Move Hub is central controller block ofLEGO® Boost Robotics Set.

In fact, Move Hub is just a Bluetooth hardware piece, and all manipulations with it are made by commands passed through Bluetooth Low Energy (BLE) wireless protocol. One of the ways to issue these commands is to write Python program using this library.

The best way to start is to look intodemo.py file, and run it (assuming you have installed library).

If you have Vernie assembled, you might run scripts fromexamples/vernie directory.

Dancing Vernie

• auto-detect and connect toMove Hub device
• auto-detectsperipheral devices connected to Hub
• constant, angled and timed movement formotors, rotation sensor subscription
• vision sensor: several modes to measure distance, color and luminosity
• tilt sensor subscription: 2 axis, 3 axis, bump detect modes
• RGB LED color change
• Headlight brightness change
• push button status subscription
• battery voltage and current subscription available

Please note that this library requires one of Bluetooth backend libraries to be installed, please read sectionhere for details.

Install library like this:

pip install -U pylgbst[bleak]

Then instantiate MoveHub object and start invoking its methods. Following is example to just print peripherals detected on Hub:

frompylgbst.hubimportMoveHubhub=MoveHub()fordeviceinhub.peripherals:print(device)

Each peripheral kind has own methods to do actions and/or get sensor data. Seefeatures list for individual doc pages.

You have following options to install as Bluetooth backend (some of them might requiresudo on Linux):

• pip install bleak -bleak lib, supports Linux/Windows/MacOS (recommended)
• pip install pygatt -pygatt lib, works on both Windows and Linux
• pip install gatt -gatt lib, supports Linux, does not work on Windows
• pip install gattlib -gattlib - supports Linux, does not work on Windows, requiressudo
• pip install bluepy -bluepy lib, supports Linux, including Raspbian, which allows connection to the hub from the Raspberry PI

Note thatpip install -U pylgbst[bleak] command indicates which backend to install. So you can install it backend-less, or with some backend from above.

Windows users may first turn to the Bleak backend, which should support any internal or external Bluetooth adapter recognized by the OS. The Windows version ofpygatt backend will only work with aBluegiga BLED112 Bluetooth Smart Dongle.

Please let author know if you have discovered any compatibility/preprequisite details, so we will update this section to help future users

Depending on backend type, you might need Linuxsudo to be used when running Python.

There is an optional parameter forMoveHub class constructor, accepting instance ofConnection object. By default, it will try to use whateverget_connection_auto() returns. You have several options to manually control that:

• useget_connection_auto() to attempt backend auto-detection
• useget_connection_bluegiga() - if you use BlueGiga Adapter (pygatt library prerequisite)
• useget_connection_gatt() - if you use Gatt Backend on Linux (gatt library prerequisite)
• useget_connection_gattool() - if you use GattTool Backend on Linux (pygatt library prerequisite)
• useget_connection_gattlib() - if you use GattLib Backend on Linux (gattlib library prerequisite)
• useget_connection_bluepy() - if you use Bluepy backend on Linux/Raspbian (bluepy library prerequisite)
• useget_connection_bleak() - if you use Bleak backend (bleak library prerequisite)

All the functions above have optional arguments to specify adapter name and Hub name (or mac address). Please take a look at functions source code for details.

If you want to specify name for Bluetooth interface to use on local computer, you can pass that to class or function of getting a connection. Then pass connection object toMoveHub constructor. Like this:

frompylgbst.hubimportMoveHubfrompylgbstimportget_connection_gattconn=get_connection_gatt(hub_mac='AA:BB:CC:DD:EE:FF')hub=MoveHub(conn)

• validate operations with other Hub types (train, PUP etc)
• make connections to detect hub by UUID instead of name
• document all API methods

• https://github.com/LEGO/lego-ble-wireless-protocol-docs - true docs for LEGO BLE protocol
• https://github.com/JorgePe/BOOSTreveng - initial source of protocol knowledge
• https://github.com/nathankellenicki/node-poweredup - JavaScript version of library
• https://github.com/spezifisch/sphero-python/blob/master/BB8joyDrive.py - example with another approach to bluetooth libs
• https://github.com/virantha/bricknil - for the lovers of async Python, alternative implementation of library to control PoweredUp Hubs
• https://virantha.github.io/bricknil/lego_api/lego.html - good infor about modes by BrickNil