树莓派只寻黑线的小车代码

以下是一份简单的树莓派小车代码，可以让小车沿着黑线行驶：

import RPi.GPIO as GPIO
import time

# 定义引脚
left_motor_forward_pin = 11
left_motor_backward_pin = 12
right_motor_forward_pin = 13
right_motor_backward_pin = 15
line_sensor_left_pin = 16
line_sensor_middle_pin = 18
line_sensor_right_pin = 22

# 初始化GPIO
GPIO.setmode(GPIO.BOARD)
GPIO.setup(left_motor_forward_pin, GPIO.OUT)
GPIO.setup(left_motor_backward_pin, GPIO.OUT)
GPIO.setup(right_motor_forward_pin, GPIO.OUT)
GPIO.setup(right_motor_backward_pin, GPIO.OUT)
GPIO.setup(line_sensor_left_pin, GPIO.IN)
GPIO.setup(line_sensor_middle_pin, GPIO.IN)
GPIO.setup(line_sensor_right_pin, GPIO.IN)

# 定义小车运动函数
def car_move(left_speed, right_speed):
    # 控制左右轮的转速
    if left_speed >= 0:
        GPIO.output(left_motor_forward_pin, GPIO.HIGH)
        GPIO.output(left_motor_backward_pin, GPIO.LOW)
        left_pwm.ChangeDutyCycle(left_speed)
    else:
        GPIO.output(left_motor_forward_pin, GPIO.LOW)
        GPIO.output(left_motor_backward_pin, GPIO.HIGH)
        left_pwm.ChangeDutyCycle(-left_speed)
        
    if right_speed >= 0:
        GPIO.output(right_motor_forward_pin, GPIO.HIGH)
        GPIO.output(right_motor_backward_pin, GPIO.LOW)
        right_pwm.ChangeDutyCycle(right_speed)
    else:
        GPIO.output(right_motor_forward_pin, GPIO.LOW)
        GPIO.output(right_motor_backward_pin, GPIO.HIGH)
        right_pwm.ChangeDutyCycle(-right_speed)

# 定义读取传感器的函数
def read_sensor():
    left = GPIO.input(line_sensor_left_pin)
    middle = GPIO.input(line_sensor_middle_pin)
    right = GPIO.input(line_sensor_right_pin)
    return (left, middle, right)

# 初始化PWM
left_pwm = GPIO.PWM(left_motor_forward_pin, 100)
left_pwm.start(0)
right_pwm = GPIO.PWM(right_motor_forward_pin, 100)
right_pwm.start(0)

# 小车沿着黑线行驶
try:
    while True:
        left, middle, right = read_sensor()
        if middle == 1:
            car_move(50, 50)
        elif left == 1:
            car_move(-30, 30)
        elif right == 1:
            car_move(30, -30)
except KeyboardInterrupt:
    pass

# 清理GPIO
GPIO.cleanup()

这份代码使用了三个红外线传感器来检测小车下方的黑线，根据传感器的读数来控制小车的转向和转速。具体来说：

- 如果中间的传感器检测到黑线，就保持直行；
- 如果左边的传感器检测到黑线，就向左转；
- 如果右边的传感器检测到黑线，就向右转。

当然，这只是一个简单的示例代码，实际应用中可能需要更复杂的算法来实现更精确的控制。