> For the complete documentation index, see [llms.txt](https://s761111.gitbook.io/raspi-sensor/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://s761111.gitbook.io/raspi-sensor/shu-mei-pai-yu-zi-zou-che/kong-zhi-ma-da-zheng-fan-zhuan-ji-chu/zi-zou-che-fang-xiang-kong-zhi.md).

# 自走車方向控制

建立一個Motor的類別，利用它來完成前進、後退、左轉、右轉等四個方向的移動，做為接續避障、巡跡等功能的基礎。

{% embed url="<https://youtu.be/bRtUD8-qgfI>" %}

```python
# 自走車馬達類別
import time
import RPi.GPIO as GPIO

class Motor:
    def __init__(self, ena, in1, in2, enb, in3, in4):
        self.ENA = ena
        self.IN1 = in1
        self.IN2 = in2
        self.ENB = enb
        self.IN3 = in3
        self.IN4 = in4
        # 設定右輪
        GPIO.setup(self.ENA, GPIO.OUT, initial=GPIO.LOW)
        # 利用PWN來改變車子馬達轉速（改變車子速度），初始值為全速100
        self.ENA_SPEED = GPIO.PWM(self.ENA, 600)
        self.ENA_SPEED.start(0)
        self.ENA_SPEED.ChangeDutyCycle(100)
        GPIO.setup(self.IN1, GPIO.OUT, initial=GPIO.LOW)
        GPIO.setup(self.IN2, GPIO.OUT, initial=GPIO.LOW)
        # 設定左輪
        GPIO.setup(self.ENB, GPIO.OUT, initial=GPIO.LOW)
        self.ENB_SPEED = GPIO.PWM(self.ENB, 600)
        self.ENB_SPEED.start(0)
        self.ENB_SPEED.ChangeDutyCycle(100)
        GPIO.setup(self.IN3, GPIO.OUT, initial=GPIO.LOW)
        GPIO.setup(self.IN4, GPIO.OUT, initial=GPIO.LOW)

    def right_speed(self, speed):
        self.ENA_SPEED.ChangeDutyCycle(speed)

    def left_speed(self, speed):
        self.ENB_SPEED.ChangeDutyCycle(speed)

    def speed(self, speed):
        self.right_speed(speed)
        self.left_speed(speed)

    def forward(self):
        GPIO.output(self.ENA, True)
        GPIO.output(self.ENB, True)
        GPIO.output(self.IN1, True)
        GPIO.output(self.IN2, False)
        GPIO.output(self.IN3, True)
        GPIO.output(self.IN4, False)

    def backward(self):
        GPIO.output(self.ENA, True)
        GPIO.output(self.ENB, True)
        GPIO.output(self.IN1, False)
        GPIO.output(self.IN2, True)
        GPIO.output(self.IN3, False)
        GPIO.output(self.IN4, True)

    def turn_left(self):
        GPIO.output(self.ENA, True)
        GPIO.output(self.ENB, True)
        GPIO.output(self.IN1, True)
        GPIO.output(self.IN2, False)
        GPIO.output(self.IN3, False)
        GPIO.output(self.IN4, True)

    def turn_right(self):
        GPIO.output(self.ENA, True)
        GPIO.output(self.ENB, True)
        GPIO.output(self.IN1, False)
        GPIO.output(self.IN2, True)
        GPIO.output(self.IN3, True)
        GPIO.output(self.IN4, False)

    def stop(self):
        GPIO.output(self.ENA, True)
        GPIO.output(self.ENB, True)
        GPIO.output(self.IN1, False)
        GPIO.output(self.IN2, False)
        GPIO.output(self.IN3, False)
        GPIO.output(self.IN4, False)

GPIO.setmode(GPIO.BCM)
GPIO.setwarnings(False)
motor = Motor(13, 19, 16, 20, 21, 26)

while True:
    # motor.speed(50)
    motor.forward()
    time.sleep(1)
    motor.backward()
    time.sleep(1)
    motor.turn_left()
    time.sleep(1)
    motor.turn_right()
    time.sleep(1)
    motor.stop()
    time.sleep(5)
```