def __init__(self, motor_left_pin1=17, motor_left_pin2=27, motor_right_pin1=23, motor_right_pin2=24,
                 line_follow_pin_left=19, line_follow_pin_right=6, 
                 servo_pin=22, us_trigger_pin=12, us_echo_pin=13 ):
        GPIO.setmode(GPIO.BCM)
        GPIO.setwarnings(False)
        
        # init modules
        self.ultrasonic = US(servo_pin, us_trigger_pin, us_echo_pin)
        self.motor = L293D(motor_left_pin1, motor_left_pin2, motor_right_pin1, motor_right_pin2)
        self.line_follow_pin_left  = line_follow_pin_left
        self.line_follow_pin_right = line_follow_pin_right
        
        GPIO.setup(self.line_follow_pin_left,  GPIO.IN)
        GPIO.setup(self.line_follow_pin_right, GPIO.IN)