ros小车视觉巡线代码

ROS小车视觉巡线代码通常涉及到图像采集、处理、控制等多个方面。其中，常用的图像处理方法包括二值化、滤波、形态学操作等，而控制方法则包括PID控制等。

下面是一个简单的ROS小车视觉巡线代码的示例：

import rospy
from sensor_msgs.msg import Image
from cv_bridge import CvBridge, CvBridgeError
import cv2

class LineFollower:

    def __init__(self):
        self.bridge = CvBridge()
        self.image_sub = rospy.Subscriber("/camera/rgb/image_raw", Image, self.callback)

    def callback(self, data):
        try:
            cv_image = self.bridge.imgmsg_to_cv2(data, "bgr8")
        except CvBridgeError as e:
            print(e)

        # 图像处理操作
        gray = cv2.cvtColor(cv_image, cv2.COLOR_BGR2GRAY)
        ret, thresh = cv2.threshold(gray, 150, 255, cv2.THRESH_BINARY)
        kernel = np.ones((5,5),np.uint8)
        closing = cv2.morphologyEx(thresh, cv2.MORPH_CLOSE, kernel)
        edges = cv2.Canny(closing,50,150,apertureSize = 3)

        # 控制操作
        _, contours, _ = cv2.findContours(edges,cv2.RETR_TREE,cv2.CHAIN_APPROX_SIMPLE)
        if len(contours)>0:
            cnt = contours
            M = cv2.moments(cnt)
            cx = int(M['m10']/M['m00'])
            cy = int(M['m01']/M['m00'])
            error = cx - w/2
            twist.linear.x = 0.1
            twist.angular.z = -error / 100.0
        else:
            twist.linear.x = 0.1
            twist.angular.z = 0.0

if __name__ == '__main__':
    rospy.init_node('line_follower')
    follower = LineFollower()
    rospy.spin()

此示例中，代码订阅了ROS中相机图像话题`/camera/rgb/image_raw`，然后进行了一系列图像处理操作，最后根据处理结果控制小车前进方向和角度。