rero:micro Extension for MicroPython

This MicroPython package/extension/library provides driver for rero:micro educational robot.

• Use from reromicro import * at the top of your program
• Use rero = reromicro() to create instance object

Here is a detailed tutorial to program rero:micro using MicroPython

Let's make some noise!

• rero:micro's built-in piezo buzzer works with the default music module that comes with MicroPython on the BBC micro:bit.
• Use import music at the top of your program

# Play melody "POWER_UP"
music.play(music.POWER_UP)

Let's move it, move it~

• Use rero.RunMotor(leftMotorSpeed, rightMotorSpeed) to navigate rero:micro. Negative speed (-100 to -1) reverses the robot (eg: -50), positive speed (1 to 100) moves it forward (eg: 80) and zero speed (0) brakes the motor. Note that the direction refers to rero:micro's movement, NOT motor's rotating direction.

• Use rero.Brake() to brake rero:micro.

# rero:micro move forward at speed 50, for 1 second
rero.RunMotor(50, 50)
sleep_ms(1000)

# rero:micro turn left at speed 30, for 500 miliseconds
rero.RunMotor(-30, 30)
sleep_ms(500)

# rero:micro brakes
rero.Brake()

Sensing obstacle

• rero.ReadUltrasonic() returns the distance in centimeter between ultrasonic sensor and any obstacle in front of it.

# Forever loop
while True:

    # Brake rero:micro when obstacle is detected at 15cm away or nearer.
    # Otherwise, keep moving forward at speed 50.
    if (rero.ReadUltrasonic() < 15):
      rero.Brake()

    else:
      rero.RunMotor(50, 50)

Line tracking

~ hint

rero.ReadLineSensors() function must be called to read all three line sensors first before using rero.LineSensorDetectsLine(rero.(x)) and/or rero.LineIrIntensity(rero.(x)) to get the result.

~

• Use rero.LineSensorDetectsLine(rero.(x)) to get the boolean value of line detection. Returns true when line is detected, otherwise false.

• Use rero.LineIrIntensity(rero.(x)) to get the reflected infrared (IR) intensity value, ranging from 0 to 1500.

# Forever loop
while True:

    # read all three line sensors first
    rero.ReadLineSensors()

    # Move forward if only center sensor detects line.
    # Turn right if only right sensor detects line.
    # Turn left if only left sensor detects line.
    # Note: This simple program ignores all other possible conditions.
    if rero.LineSensorDetectsLine(rero.centerSensor):
      rero.RunMotor(50, 50)

    elif rero.LineSensorDetectsLine(rero.rightSensor):
       rero.RunMotor(-40, 40)

     elif rero.LineSensorDetectsLine(rero.leftSensor):
       rero.RunMotor(40, -40)

Colour Splash!

• This robot also has 7x NeoPixels (WS2812B programmable RGB LEDs) built-in.
• Use import neopixel at the top of your program

~ hint

See bbcmicrobit/micropython-neopixel for NeoPixels support.

~

# Create a NeoPixel strip at pin P1 with 7 LEDs
strip = neopixel.NeoPixel(pin1, 7)

# Show red colour for 1 sec.
for LED in range(7):
        strip[LED] = (255,0,0)
        strip.show()
sleep_ms(1000)

# Show blue colour for 1 sec.
for LED in range(7):
        strip[LED] = (0,0,255)
        strip.show()
sleep_ms(1000)