25 霍曼轨道 .txt

霍曼轨道的模拟图形

25 霍曼轨道 

figure 

for j=1:3 

time1=[2.3;2.1;2.3]; 

time2=[2.3;2.1;0.84]; 

v=[2.1;3.5;2.74]; 

[t1,z1]=ode45('hmgdfun',[0:0.01:time1(j)],[10,0,0,2.98],[],8900); 

[t2,z2]=ode45('hmgdfun',[0:0.01:time1(j)],[7.2,0,(-pi/3+pi*0.01),4.88],[],8900); 

[t3,z3]=ode45('hmgdfun',[0:0.01:time2(j)],[10,0,0,v(j)],[],8900); 

[x1,u1]=pol2cart(z1(:,3),z1(:,1)); %\fs{将极坐标变换为直角坐标} 

[x2,u2]=pol2cart(z2(:,3),z2(:,1)); 

[x3,u3]=pol2cart(z3(:,3),z3(:,1)); 

plot(x1(:),u1(:),'y',x2(:),u2(:),'y',x3(:),u3(:),'b') 

hold on 

axis off 

%\fs{以下是太阳,地球,金星,飞船的图形句柄} 

sun=line(0,0,'color','r','erasemode','xor','marker','.','markersize',80); 

earth=line(10,0,'color','b','marker','.','erasemode','xor','markersize',40); 

venus=line(7.2,0,'color','m','marker','.','erasemode','xor','markersize',30); 

ship=line(10,0,'color','r','marker','p','erasemode','xor','markersize',10); 

%\fs{以下text中的内容均为图示标注} 

if j==1 

view(0,58) 

title('霍曼轨道 ') 

text(-10,-10,-1,'方位角：0度；仰角：58度') 

text(-4,19,1,'依次为太阳，地球，金星，飞船 ') 

text(-8,32,1,'当宇宙飞船小于相切速度时，宇宙飞船的轨道将与金星的相交。虽然') 

text(-10,28,1,'这种情况下宇宙飞船也有可能与金星相遇，但若要将宇宙飞船降落在金星上，') 

text(-10,24,1,'它的速度需要改变很大，需要极大能量.') 

sun00=line(-8,35,'color','r','marker','.','markersize',18); 

earth11=line(-7,35,'color','b','marker','.','markersize',14); 

venus22=line(-6,35,'color','m','marker','.','markersize',12); 

ship33=line(-5,35,'color','r','marker','p','markersize',10); 

elseif j==2 

view(-90,50) 

text(-65,16,1,'方位角：-90度；仰角：50度'); 

text(-4,8,1,'依次为太阳，地球，金星，飞船 '); 

text(-1,15,1,'当宇宙飞船的速度大于相切速度时，宇宙飞船的轨道将不与金星的轨道相交。') 

sun00=line(-4,12,1,'color','r','marker','.','markersize',18); 

earth11=line(-4,11,1,'color','b','marker','.','markersize',14); 

venus22=line(-4,10,1,'color','m','marker','.','markersize',12); 

ship33=line(-4,9,1,'color','r','marker','p','markersize',10); 

else j==3 

view(1,54) 

text(-10,-10,-1,'方位角：1度；仰角：54度') 

text(-6,12,1,'依次为太阳，地球，金星，飞船 ') 

text(-10,16,1,'当宇宙飞船的速度等于相切速度时，宇宙飞船的轨道将与金星的轨道相切。') 

sun00=line(-10,27,'color','r','marker','.','markersize',18); 

earth11=line(-9,27,'color','b','marker','.','markersize',14); 

venus22=line(-8,27,'color','m','marker','.','markersize',12); 

ship33=line(-7,27,'color','r','marker','p','markersize',10); 

end 

n1=length(t3); 

for i=1:n1 

set(earth,'xdata',x1(i),'ydata',u1(i)); 

set(venus,'xdata',x2(i),'ydata',u2(i)); 

set(ship,'xdata',x3(i),'ydata',u3(i)); 

drawnow; 

pause(0.1); 

end 

if j==3 

n2=length(t2); 

for i=86:n2 %\fs{飞船降落在金星后将按金星的轨道方程运动} 

set(earth,'xdata',x1(i),'ydata',u1(i)); 

set(venus,'xdata',x2(i),'ydata',u2(i)); 

set(ship,'xdata',x2(i),'ydata',u2(i)); 

drawnow; 

pause(0.1); 

end 

end 

cla 

end