RoboMaze Cheat Sheet

Use this whenever you cannot remember what a piece of code does. You do not need to memorise everything here.

The Three Important Variables

speed = 0
turnTime = 0
distanceToWall = 0

speed

Controls how fast the motors move.

turnTime

Controls how long the motors run during a turn, in milliseconds.

distanceToWall

Controls how close the MicroMouse gets to a wall before move_to_wall() stops.

The numbers above are placeholders. Use the values you discover while testing.

Comments

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Functions

Create a function:

def my_function():
    # Code goes here
    pass

Call a function:

my_function()

Do not forget the () when calling a function.

Copying and Adapting a Function

You do not always need to start from nothing.

If you already have a similar working function, copy it and change only the parts that need to behave differently.

That is what you do when creating turn_left_90() from turn_right_90().

Turn On a Motor

Left motor forwards:

Kitronik_Move_Motor.motor_on(
    Kitronik_Move_Motor.Motors.MOTOR_LEFT,
    Kitronik_Move_Motor.MotorDirection.FORWARD,
    speed
)

Left motor backwards:

Kitronik_Move_Motor.motor_on(
    Kitronik_Move_Motor.Motors.MOTOR_LEFT,
    Kitronik_Move_Motor.MotorDirection.REVERSE,
    speed
)

Change MOTOR_LEFT to MOTOR_RIGHT to control the other wheel.

Stop the MicroMouse

Kitronik_Move_Motor.stop()

Pause

basic.pause(1000)

The value is in milliseconds.

• 1000 milliseconds = 1 second
• 500 milliseconds = 0.5 seconds
• 100 milliseconds = 0.1 seconds

RoboMaze uses:

basic.pause(turnTime)

so changing turnTime changes how long the MicroMouse spends turning.

Measure the Distance Ahead

Kitronik_Move_Motor.measure()

The starter code configures this measurement in centimetres.

Show the Measured Distance

basic.show_number(Kitronik_Move_Motor.measure())

Use this in Task 4 to help choose distanceToWall.

Understand the Supplied while Loop

while Kitronik_Move_Motor.measure() > distanceToWall:
    # movement code

This means:

Keep repeating the indented code while the measured distance is greater than distanceToWall.

Build the Final Route

By Task 6 you will have:

move_to_wall()
turn_right_90()
turn_left_90()

Call them in sequence:

def navigate_maze():
    move_to_wall()
    turn_right_90()
    move_to_wall()

The order of the function calls determines the route through the maze.

Something Has Gone Wrong?

If your code becomes badly broken, return to the Starter Code page and copy a fresh version.