We recommend against plotting and replotting within a loop. We recommend that you instead build the graphics objects before the loop, and then in the loop, update the properties of the graphics objects. Or sometimes it is easier to write, for example:
xr3=-10
yr3=0
r4m=linspace(degtorad(theta4),3*pi/2,100)
thetawl1=(r4+2)*cos(r4m)+xr3
thetawl2=(r4+2)*sin(r4m)+yr3
xcircle=(r4+5)*cos(r4m)+xr3
ycircle=(r4+5)*sin(r4m)+yr3
for i=1:1:length(r4m)
if i == 1
L1 = plot([xr3,thetawl1(i)],[yr3,thetawl2(i)],'r-')
hold on
wheel = rectangle('Position',[xcircle(i) ycircle(i) 6 6],'Curvature',[1,1],'LineWidth',10)
hold off
axis equal
axis ([-15 10 -20 5])
else
set(L1, 'XData', [xr3,thetawl1(i)], 'YData', [yr3,thetawl2(i)]);
set(wheel, 'Position', [xcircle(i) ycircle(i) 6 6]);
end
getframe
end
