基于视觉的巡监小车中的避障算法A*算法代码

A*算法是一种常用的路径规划算法，适用于基于视觉的巡检小车的避障问题。下面是A*算法的代码实现：

# 定义节点类
class Node:
    def __init__(self, x, y):
        self.x = x
        self.y = y
        self.g = 0
        self.h = 0
        self.f = 0
        self.parent = None

    def __eq__(self, other):
        return self.x == other.x and self.y == other.y

    def __str__(self):
        return f"({self.x}, {self.y})"

# 定义A*算法函数
def astar(start, end, obstacles):
    open_list = []
    closed_list = []

    start_node = Node(start[0], start[1])
    end_node = Node(end[0], end[1])

    open_list.append(start_node)

    while len(open_list) > 0:
        current_node = open_list[0]
        current_index = 0

        for index, item in enumerate(open_list):
            if item.f < current_node.f:
                current_node = item
                current_index = index

        open_list.pop(current_index)
        closed_list.append(current_node)

        if current_node == end_node:
            path = []
            current = current_node
            while current is not None:
                path.append(current)
                current = current.parent
            return path[::-1]

        children = []
        for new_position in [(0, -1), (0, 1), (-1, 0), (1, 0)]:
            node_position = (current_node.x + new_position[0], current_node.y + new_position[1])

            if node_position[0] > (len(obstacles) - 1) or node_position[0] < 0 or node_position[1] > (len(obstacles[len(obstacles)-1]) -1) or node_position[1] < 0:
                continue

            if obstacles[node_position[0]][node_position[1]] != 0:
                continue

            new_node = Node(node_position[0], node_position[1])
            children.append(new_node)

        for child in children:
            for closed_child in closed_list:
                if child == closed_child:
                    continue

            child.g = current_node.g + 1
            child.h = ((child.x - end_node.x) ** 2) + ((child.y - end_node.y) ** 2)
            child.f = child.g + child.h

            for open_node in open_list:
                if child == open_node and child.g > open_node.g:
                    continue

            open_list.append(child)
            child.parent = current_node

    return None

其中，start和end表示起点和终点的坐标，obstacles表示障碍物的位置信息，代码中使用了Node类来表示节点，open_list和closed_list分别存储已经检查过和未检查过的节点。在循环中，首先选择f值最小的节点进行检查，然后对节点周围的子节点进行检查和更新，直到找到终点或者open_list为空。最后通过遍历节点的parent指针，得到从起点到终点的路径。