Subclass of WiimoteConnect for controlling a real Pi-driven Lego-based forklift truck.

wiibot.py

import piface.pfio as pfio
from wiimote import WiimoteConnect


class WiiBot(WiimoteConnect):
    """
    Use Wiimote to control robot

    Basic usage:
        from wiibot import WiiBot
        bot = WiiBot()
        bot.connect()
        bot.start()
        ...
        bot.stop()
        bot.disconnect()
    """

    LEFT_WHEEL = 0
    RIGHT_WHEEL = 1
    LEFT_WHEEL_POLARITY = 2
    RIGHT_WHEEL_POLARITY = 3
    FORKLIFT = 4
    FORKLIFT_POLARITY = 5
    FORKLIFT_SWITCH_UPPER = 0
    FORKLIFT_SWITCH_LOWER = 1
    FORKS_MOVING = False
    ON = 1
    OFF = 0

    def write(self, target, action):
        pfio.digital_write(target, action)

    def __init__(self):
        super(WiiBot, self).__init__()
        pfio.init()
        self.freq = 10

    def forward(self):
        self.write(self.LEFT_WHEEL_POLARITY, self.OFF)
        self.write(self.RIGHT_WHEEL_POLARITY, self.OFF)
        self.write(self.LEFT_WHEEL, self.ON)
        self.write(self.RIGHT_WHEEL, self.ON)

    def reverse(self):
        self.write(self.LEFT_WHEEL_POLARITY, self.ON)
        self.write(self.RIGHT_WHEEL_POLARITY, self.ON)
        self.write(self.LEFT_WHEEL, self.ON)
        self.write(self.RIGHT_WHEEL, self.ON)

    def left(self):
        self.write(self.LEFT_WHEEL_POLARITY, self.ON)
        self.write(self.RIGHT_WHEEL_POLARITY, self.OFF)
        self.write(self.LEFT_WHEEL, self.ON)
        self.write(self.RIGHT_WHEEL, self.ON)

    def right(self):
        self.write(self.LEFT_WHEEL_POLARITY, self.OFF)
        self.write(self.RIGHT_WHEEL_POLARITY, self.ON)
        self.write(self.LEFT_WHEEL, self.ON)
        self.write(self.RIGHT_WHEEL, self.ON)

    def forks_start(self):
        self.FORKS_MOVING = True
        self.write(self.FORKLIFT, self.ON)

    def forks_stop(self):
        self.FORKS_MOVING = False
        self.write(self.FORKLIFT, self.OFF)
        self.write(self.FORKLIFT_POLARITY, self.OFF)

    def forks_move(self, down):
        self.write(self.FORKLIFT_POLARITY, down)
        self.forks_start()
        while not self.forks_at_limit() and self.FORKS_MOVING:
            pass
        self.forks_stop()

    def forks_at_limit(self):
        at_limit = (
            pfio.digital_read(self.FORKLIFT_SWITCH_LOWER) == 1 or
            pfio.digital_read(self.FORKLIFT_SWITCH_UPPER) == 1
        )
        at_limit and self._pulse_rumble(0.25)
        return at_limit

    def brake(self):
        self.write(self.LEFT_WHEEL, self.OFF)
        self.write(self.RIGHT_WHEEL, self.OFF)
        self.write(self.LEFT_WHEEL_POLARITY, self.OFF)
        self.write(self.RIGHT_WHEEL_POLARITY, self.OFF)

    def _btn_left(self, is_down):
        if is_down:
            self.left()
            self.leds(led1=True, led4=False)
        else:
            self.brake()
            self.leds(led1=False)

    def _btn_right(self, is_down):
        if is_down:
            self.right()
            self.leds(led1=False, led4=True)
        else:
            self.brake()
            self.leds(led4=False)

    def _btn_up(self, is_down):
        if is_down:
            if not (self.is_pressed(self.BTN_LEFT) or self.is_pressed(self.BTN_RIGHT)):
                self.forward()
        else:
            self.brake()

    def _btn_down(self, is_down):
        if is_down:
            if not (self.is_pressed(self.BTN_LEFT) or self.is_pressed(self.BTN_RIGHT)):
                self.reverse()
        else:
            self.brake()

    def _btn_plus(self, is_down):
        if is_down:
            self.forks_move(down=False)

    def _btn_minus(self, is_down):
        if is_down and not (self.is_pressed(self.BTN_PLUS)):
            self.forks_move(down=True)

    def _btn_a(self, is_down):
        if is_down:
            self.forks_move(down=False)
        else:
            self.FORKS_MOVING = False

    def _btn_b(self, is_down):
        if is_down:
            if not self.is_pressed(self.BTN_A):
                self.forks_move(down=True)
        else:
            self.FORKS_MOVING = False

    def _btn_home(self, is_down):
        pass

    def _btn_2(self, is_down):
        pass

    def _btn_1(self, is_down):
        pass

Haven't tested this version with the physical bot yet. The previous revision works fine in case this is buggy.