Matlab航迹规划仿真——A*算法
作者：互联网
文章目录
基本的A*算法在这里不再讲述，想要了解的朋友可以自己在CSDN搜索，在此主要解释下代码。
1. 初始化参数
主要参数:
- 地图大小
- 起始点和目标点坐标
clc
clear all
m = 30;n = 30;
Spoint = [3 3]; %起始点坐标
Epoint = [29 22]; %目标点坐标
2. 构建地图
-inf表示不可到达的障碍物点
%%构建地图
for i = 1:m+2
if i == 1
for j = 1:n+2
Matrix(i,j) = -inf;
end
elseif i == m+2
for j = 1:n+2
Matrix(i,j) = -inf;
end
else
for j = 1:n+2
if ((j == 1)|(j == n+2))
Matrix(i,j) = -inf;
else
Matrix(i,j) = inf;
end
end
end
end
%%障碍
for j=2:10
Matrix(5,j)=-inf;
for j=2:15
Matrix(24,j)=-inf;
for j=9:24
%for j=6:24
Matrix(10,j)=-inf;
for j=20:31
Matrix(15,j)=-inf;
for j=5:20
Matrix(20,j)=-inf;
for j=18:27
Matrix(28,j)=-inf;
for i=2:6
Matrix(i,18)=-inf;
for i=17:20
Matrix(i,5)=-inf;
for i=23:25
Matrix(i,20)=-inf;
for i=13:17
Matrix(i,13)=-inf;
end
end
end
end
end
end
end
end
end
end
%end
% 显示地图
%subplot(2,2,1);
h1 = plot(Spoint(1),Spoint(2),'gO');
hold on
h2 = plot(Epoint(1),Epoint(2),'rO');
3. A*算法搜索路径
%%寻路
Matrix(Spoint(1),Spoint(2))=0;
Matrix(Epoint(1),Epoint(2))=inf;
G=Matrix;
F=Matrix;
openlist=Matrix;
closelist=Matrix;
parentx=Matrix;
parenty=Matrix;
openlist(Spoint(1),Spoint(2)) =0;
%closelist(Epoint(1),Epoint(2))=inf;
for i = 1:n+2
for j = 1:m+2
k = Matrix(i,j);
if(k == -inf)
%subplot(2,2,1);
h3 = plot(i,j,'k.');
% elseif(k == inf) % show green feasible point
% %subplot(2,2,1);
% plot(i,j,'gh');
% else
% %subplot(2,2,1);
% plot(i,j,'gh');
end
hold on
end
end
axis([0 m+3 0 n+3]);
%subplot(2,2,1);
plot(Epoint(1),Epoint(2),'b+');
%subplot(2,2,1);
plot(Spoint(1),Spoint(2),'b+');
while(1)
num=inf;
for p=1:m+2
for q=1:n+2
if(openlist(p,q)==0&&closelist(p,q)~=1)
Outpoint=[p,q];
if(F(p,q)>=0&&num>F(p,q))
num=F(p,q);
Nextpoint=[p,q];
end
end
end
end
closelist(Nextpoint(1),Nextpoint(2))=1;
for i = 1:3
for j = 1:3
k = G(Nextpoint(1)-2+i,Nextpoint(2)-2+j);
if(i==2&&j==2|closelist(Nextpoint(1)-2+i,Nextpoint(2)-2+j)==1)
continue;
elseif (k == -inf)
G(Nextpoint(1)-2+i,Nextpoint(2)-2+j) = G(Nextpoint(1)-2+i,Nextpoint(2)-2+j);
closelist(Nextpoint(1)-2+i,Nextpoint(2)-2+j)=1;
elseif (k == inf)
distance=((i-2)^2+(j-2)^2)^0.5;
G(Nextpoint(1)-2+i,Nextpoint(2)-2+j)=G(Nextpoint(1),Nextpoint(2))+distance;
openlist(Nextpoint(1)-2+i,Nextpoint(2)-2+j)=0;
% H=((Nextpoint(1)-2+i-Epoint(1))^2+(Nextpoint(2)-2+j-Epoint(2))^2)^0.5;%欧几里德距离启发函数
H_diagonal=min(abs(Nextpoint(1)-2+i-Epoint(1)),abs(Nextpoint(2)-2+j-Epoint(2)));%比较复杂的对角线启发函数
H_straight=abs(Nextpoint(1)-2+i-Epoint(1))+abs(Nextpoint(2)-2+j-Epoint(2));
H=sqrt(2)*H_diagonal+(H_straight-2*H_diagonal);
% H=max(abs(Nextpoint(1)-2+i-Epoint(1)),abs(Nextpoint(2)-2+j-Epoint(2)));%比较简单的对角线函数
F(Nextpoint(1)-2+i,Nextpoint(2)-2+j)=G(Nextpoint(1)-2+i,Nextpoint(2)-2+j)+H;
parentx(Nextpoint(1)-2+i,Nextpoint(2)-2+j)=Nextpoint(1);
parenty(Nextpoint(1)-2+i,Nextpoint(2)-2+j)=Nextpoint(2);
else distance=((i-2)^2+(j-2)^2)^0.5;
if(k>(distance+G(Nextpoint(1),Nextpoint(2))))
k=distance+G(Nextpoint(1),Nextpoint(2));
% H=((Nextpoint(1)-2+i-Epoint(1))^2+(Nextpoint(2)-2+j-Epoint(2))^2)^0.5; %欧几里德距离启发函数
H_diagonal=min(abs(Nextpoint(1)-2+i-Epoint(1)),abs(Nextpoint(2)-2+j-Epoint(2)));%比较复杂的对角线启发函数
H_straight=abs(Nextpoint(1)-2+i-Epoint(1))+abs(Nextpoint(2)-2+j-Epoint(2));
H=sqrt(2)*10*H_diagonal+10*(H_straight-2*H_diagonal);
% H=max(abs(Nextpoint(1)-2+i-Epoint(1)),abs(Nextpoint(2)-2+j-Epoint(2)));%比较简单的对角线函数
F(Nextpoint(1)-2+i,Nextpoint(2)-2+j)=k+H;
parentx(Nextpoint(1)-2+i,Nextpoint(2)-2+j)=Nextpoint(1);
parenty(Nextpoint(1)-2+i,Nextpoint(2)-2+j)=Nextpoint(2);
end
end
if(((Nextpoint(1)-2+i)==Epoint(1)&&(Nextpoint(2)-2+j)==Epoint(2))|num==inf)
parentx(Epoint(1),Epoint(2))=Nextpoint(1);
parenty(Epoint(1),Epoint(2))=Nextpoint(2);
break;
end
end
if(((Nextpoint(1)-2+i)==Epoint(1)&&(Nextpoint(2)-2+j)==Epoint(2))|num==inf)
parentx(Epoint(1),Epoint(2))=Nextpoint(1);
parenty(Epoint(1),Epoint(2))=Nextpoint(2);
break;
end
end
if(((Nextpoint(1)-2+i)==Epoint(1)&&(Nextpoint(2)-2+j)==Epoint(2))|num==inf)
parentx(Epoint(1),Epoint(2))=Nextpoint(1);
parenty(Epoint(1),Epoint(2))=Nextpoint(2);
break;
end
end
P=[];
s=1;
while(1)
if(num==inf)
break;
end
%subplot(2,2,1);
h4 = plot(Epoint(1),Epoint(2),'b+');
P(s,:)=Epoint;
s=s+1;
% pause(1);
xx=Epoint(1);
Epoint(1)=parentx(Epoint(1),Epoint(2));
Epoint(2)=parenty(xx,Epoint(2));
if(parentx(Epoint(1),Epoint(2))==Spoint(1)&&parenty(Epoint(1),Epoint(2))==Spoint(2))
%subplot(2,2,1);
plot(Epoint(1),Epoint(2),'b+');
P(s,:)=Epoint;
break;
end
end
P(s+1,:)=Spoint;
legend([h1,h2,h3,h4],'起始点','目标点','障碍物','航迹点');
count=0;
for i=2:12
for j=2:12
if(G(i,j)~=inf&&G(i,j)~=-inf)
count=count+1;
end
end
end
count
4. 路径优化
%将得到的折现曲线拟合成光滑的曲线
P=P';
a=[];
b=[];
a=P(1,:);
b=P(2,:);
figure
%subplot(2,2,3);
plot(a,b);
axis([0,n+3,0,n+3]);
values = spcrv([[a(1) a a(end)];[b(1) b b(end)]],3);
figure
%subplot(2,2,4);
plot(values(1,:),values(2,:),'r');
axis([0,m+3,0,m+3]);
5. 效果图
A*路径
优化后路径
6. 下载链接
直接复制到matlab即可使用，或者也可以点击下载
(68条消息) Matlab航迹规划仿真——A*算法_漫长IT路-CSDN博客_matlab 航迹规划
标签：仿真,Spoint,end,航迹,Epoint,Matlab,Nextpoint,inf,Matrix 来源： https://blog.csdn.net/tjcwt2011/article/details/106664119