基于一些智能算法的栅格图路径规划matlab
时间: 2023-07-26 12:38:58 浏览: 90
基于遗传算法的栅格法机器人路径规划的MATLAB仿真,matlab2021a测试
在MATLAB中,可以使用一些智能算法进行栅格图路径规划。下面是一个基于A*算法的栅格图路径规划示例:
1. 定义栅格图
首先,定义一个栅格图。可以使用二维数组来表示栅格图,其中0表示可通过的区域,1表示障碍物。
```matlab
grid = [0,0,0,0,0,0,0,0,0,0;
0,1,0,0,0,0,1,0,0,0;
0,0,0,0,0,0,1,0,0,0;
0,0,0,0,0,0,1,1,0,0;
0,0,0,0,0,0,0,0,0,0;
0,0,0,0,0,0,0,0,0,0;
0,0,0,0,0,0,0,0,0,0;
0,0,0,0,0,0,0,0,0,0;
0,0,0,0,0,0,0,0,0,0;
0,0,0,0,0,0,0,0,0,0];
```
2. 定义起点和终点
接下来,定义起点和终点的坐标。
```matlab
start = [1,1];
goal = [3,8];
```
3. 定义A*算法
然后,定义A*算法。A*算法是一种启发式搜索算法,可以用于在栅格图中寻找最短路径。可以使用以下代码定义A*算法:
```matlab
function [path, cost] = A_star(grid, start, goal)
% 定义A*算法
% 输入:栅格图,起点坐标,终点坐标
% 输出:路径,路径长度
% 初始化
closed = zeros(size(grid));
expand = zeros(size(grid));
action = [-1, 0; 0, -1; 1, 0; 0, 1];
cost = 1;
pq = priorityqueue();
pq.insert(start, 0);
% 开始搜索
while ~pq.isempty()
% 获取当前节点
[current, ~] = pq.pop();
if isequal(current, goal)
break;
end
% 标记当前节点为已扩展
expand(current(1), current(2)) = 1;
% 扩展当前节点
for i = 1:size(action, 1)
next = current + action(i,:);
% 检查是否越界或已扩展或是障碍物
if next(1) < 1 || next(1) > size(grid, 1) || ...
next(2) < 1 || next(2) > size(grid, 2) || ...
closed(next(1), next(2)) == 1 || ...
grid(next(1), next(2)) == 1
continue;
end
% 计算代价
g = cost + heuristic(current, next);
% 检查是否已在队列中
if pq.contains(next)
% 更新代价
if pq.getcost(next) > g
pq.update(next, g);
end
else
% 加入队列
pq.insert(next, g);
end
% 标记下一个节点为已扩展
closed(next(1), next(2)) = 1;
end
end
% 构建路径
path = [];
if isequal(current, goal)
while ~isequal(current, start)
path = [current; path];
current = pq.getparent(current);
end
path = [start; path];
end
```
其中,priorityqueue是MATLAB内置的优先队列类,用于存储待扩展的节点。
4. 定义启发函数
在A*算法中,还需要定义一个启发函数,用于估算当前节点到终点的距离。可以使用曼哈顿距离作为启发函数。以下是启发函数的定义:
```matlab
function h = heuristic(current, goal)
% 定义曼哈顿距离启发函数
% 输入:当前节点坐标,终点坐标
% 输出:当前节点到终点的曼哈顿距离
h = abs(current(1) - goal(1)) + abs(current(2) - goal(2));
end
```
5. 运行A*算法
最后,运行A*算法并绘制路径。以下是完整的代码:
```matlab
% 定义栅格图
grid = [0,0,0,0,0,0,0,0,0,0;
0,1,0,0,0,0,1,0,0,0;
0,0,0,0,0,0,1,0,0,0;
0,0,0,0,0,0,1,1,0,0;
0,0,0,0,0,0,0,0,0,0;
0,0,0,0,0,0,0,0,0,0;
0,0,0,0,0,0,0,0,0,0;
0,0,0,0,0,0,0,0,0,0;
0,0,0,0,0,0,0,0,0,0;
0,0,0,0,0,0,0,0,0,0];
% 定义起点和终点
start = [1,1];
goal = [3,8];
% 运行A*算法
[path, cost] = A_star(grid, start, goal);
% 绘制栅格图和路径
figure;
imagesc(grid);
hold on;
plot(path(:,2), path(:,1), 'r', 'LineWidth', 2);
plot(start(2), start(1), 'bo', 'MarkerSize', 10, 'LineWidth', 2);
plot(goal(2), goal(1), 'go', 'MarkerSize', 10, 'LineWidth', 2);
hold off;
axis equal;
title(sprintf('A* Algorithm\nPath Length: %.2f', cost));
```
这个示例演示了如何使用A*算法进行栅格图路径规划。需要注意的是,还有许多其他智能算法可以用于栅格图路径规划,如Dijkstra、RRT等。你可以根据自己的需要选择适合的算法。
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