小车避障摄像头Python代码

以下是使用树莓派和OpenCV库实现小车避障的Python代码，其中摄像头连接到树莓派上，可以通过OpenCV库进行视频流的捕获和处理。

import cv2
import numpy as np
import RPi.GPIO as GPIO
import time

# 声明GPIO口
GPIO.setmode(GPIO.BOARD)
GPIO.setwarnings(False)
Motor_A_EN = 11
Motor_A_Pin1 = 13
Motor_A_Pin2 = 15
Motor_B_EN = 12
Motor_B_Pin1 = 16
Motor_B_Pin2 = 18

# 设置GPIO口为输出
GPIO.setup(Motor_A_EN, GPIO.OUT)
GPIO.setup(Motor_A_Pin1, GPIO.OUT)
GPIO.setup(Motor_A_Pin2, GPIO.OUT)
GPIO.setup(Motor_B_EN, GPIO.OUT)
GPIO.setup(Motor_B_Pin1, GPIO.OUT)
GPIO.setup(Motor_B_Pin2, GPIO.OUT)

# 设置PWM频率
pwm_A_EN = GPIO.PWM(Motor_A_EN, 2000)
pwm_B_EN = GPIO.PWM(Motor_B_EN, 2000)
pwm_A_EN.start(0)
pwm_B_EN.start(0)

# 小车前进
def forward():
    GPIO.output(Motor_A_Pin1, GPIO.HIGH)
    GPIO.output(Motor_A_Pin2, GPIO.LOW)
    GPIO.output(Motor_B_Pin1, GPIO.HIGH)
    GPIO.output(Motor_B_Pin2, GPIO.LOW)
    pwm_A_EN.ChangeDutyCycle(80)
    pwm_B_EN.ChangeDutyCycle(80)

# 小车后退
def backward():
    GPIO.output(Motor_A_Pin1, GPIO.LOW)
    GPIO.output(Motor_A_Pin2, GPIO.HIGH)
    GPIO.output(Motor_B_Pin1, GPIO.LOW)
    GPIO.output(Motor_B_Pin2, GPIO.HIGH)
    pwm_A_EN.ChangeDutyCycle(80)
    pwm_B_EN.ChangeDutyCycle(80)

# 小车左转
def turn_left():
    GPIO.output(Motor_A_Pin1, GPIO.HIGH)
    GPIO.output(Motor_A_Pin2, GPIO.LOW)
    GPIO.output(Motor_B_Pin1, GPIO.LOW)
    GPIO.output(Motor_B_Pin2, GPIO.HIGH)
    pwm_A_EN.ChangeDutyCycle(60)
    pwm_B_EN.ChangeDutyCycle(60)

# 小车右转
def turn_right():
    GPIO.output(Motor_A_Pin1, GPIO.LOW)
    GPIO.output(Motor_A_Pin2, GPIO.HIGH)
    GPIO.output(Motor_B_Pin1, GPIO.HIGH)
    GPIO.output(Motor_B_Pin2, GPIO.LOW)
    pwm_A_EN.ChangeDutyCycle(60)
    pwm_B_EN.ChangeDutyCycle(60)

# 小车停止
def stop():
    GPIO.output(Motor_A_Pin1, GPIO.LOW)
    GPIO.output(Motor_A_Pin2, GPIO.LOW)
    GPIO.output(Motor_B_Pin1, GPIO.LOW)
    GPIO.output(Motor_B_Pin2, GPIO.LOW)
    pwm_A_EN.ChangeDutyCycle(0)
    pwm_B_EN.ChangeDutyCycle(0)

# 定义红色和绿色的HSV值范围
lower_red = np.array([0, 100, 100])
upper_red = np.array([10, 255, 255])
lower_green = np.array([50, 100, 100])
upper_green = np.array([70, 255, 255])

# 打开摄像头
cap = cv2.VideoCapture(0)

while True:
    ret, frame = cap.read()
    if not ret:
        break

    # 将视频帧转换为HSV格式
    hsv = cv2.cvtColor(frame, cv2.COLOR_BGR2HSV)

    # 提取红色和绿色区域的二进制掩码
    mask_red = cv2.inRange(hsv, lower_red, upper_red)
    mask_green = cv2.inRange(hsv, lower_green, upper_green)

    # 对掩码进行形态学操作，以去除噪声
    kernel = np.ones((5,5), np.uint8)
    mask_red = cv2.erode(mask_red, kernel, iterations=2)
    mask_red = cv2.dilate(mask_red, kernel, iterations=2)
    mask_green = cv2.erode(mask_green, kernel, iterations=2)
    mask_green = cv2.dilate(mask_green, kernel, iterations=2)

    # 找到红色和绿色区域的轮廓
    contours_red, _ = cv2.findContours(mask_red, cv2.RETR_TREE, cv2.CHAIN_APPROX_SIMPLE)
    contours_green, _ = cv2.findContours(mask_green, cv2.RETR_TREE, cv2.CHAIN_APPROX_SIMPLE)

    # 如果有红色区域，则小车后退
    if len(contours_red) > 0:
        backward()
        time.sleep(0.5)
        stop()
        time.sleep(0.5)
    # 如果有绿色区域，则小车前进
    elif len(contours_green) > 0:
        forward()
    # 否则小车左转
    else:
        turn_left()

    # 显示视频流
    cv2.imshow('frame', frame)

    # 按下q键退出程序
    if cv2.waitKey(1) == ord('q'):
        break

# 释放资源
cap.release()
cv2.destroyAllWindows()

需要注意的是，该代码中使用了PWM调速控制小车的速度，可以根据实际情况进行调整。此外，HSV值范围也可以根据实际情况进行调整。