bricknil 0.5

Control LEGO(tm) BluetoothLE Hubs, Motors, and Sensors using Async Python

BrickNil [*] provides an easy way to connect to and program LEGO® Bluetooth hubs (including the newer 60197 and 60198 train sets) using Python on OS X and Linux. This work was inspired by this EuroBricks thread, and the NodeJS Powered-Up library. It requires modern Python (designed and tested for 3.7) and uses asynchronous event programming built on top of the Curio async library. As an aside, the choice of async library is fairly arbitrary; and conceivably enabling another library such as asyncio or Trio should be straightforward.

An example BrickNil program for controlling the Train motor speed is shown below:

from curio import sleep
from bricknil import attach, start
from bricknil.hub import PoweredUpHub
from bricknil.sensor import TrainMotor

@attach(TrainMotor, name='motor')
class Train(PoweredUpHub):

    async def run(self):
        for i in range(2):  # Repeat this control two times
            await self.motor.ramp_speed(80,5000) # Ramp speed to 80 over 5 seconds
            await sleep(6)
            await self.motor.ramp_speed(0,1000)  # Brake to 0 over 1 second
            await sleep(2)

async def system():
    train = Train('My train')

if __name__ == '__main__':
    start(system)

• Free and open-source software: ASL2 license

• Documentation: http://virantha.github.io/bricknil

• Source: https://github.com/virantha/bricknil

[*]

BrickNil’s name comes from the word “Nil” (නිල්) in Sinhala which means Blue (as in Bluetooth)

Features

• Supports the following LEGO® Bluetooth systems:

  • PoweredUp hubs for trains

  • Boost Move hub

• Supports the following actuators/sensors:

  • Internal motors

  • Train motors

  • Hub LED color

  • Boost vision sensor (color, distance)

  • Internal tilt/orientation/accelerometer

  • Hub buttons

• Fully supports Python asynchronous keywords and coroutines

  • Allows expressive concurrent programming using async/await syntax

  • The current implmentation uses the async library Curio by David Beazley

• Cross-platform

  • Uses the Adafruit Bluefruit BluetoothLE library for Mac OS X

  • Uses the Bleak Bluetooth library for Linux and Win10[†], tested on Raspberry Pi

[†]

Untested

Building a simple train controller