铰链六杆机构的运动分析(2)

y(9)=y(6)-20; x(10)=x(6)-40; y(10)=y(6)+20; x(11)=x(6)+40; y(11)=y(6)+20; i=1:6;

plot(x(i),y(i)); grid on;hold on; i=7:11;

plot(x(i),y(i));

plot(x(1),y(1),'o'); plot(x(2),y(2),'o'); plot(x(3),y(3),'o'); plot(x(4),y(4),'o'); plot(x(5),y(5),'o'); plot(x(6),y(6),'o'); title('曲柄滑块机构'); grid on;hold on; xlabel('mm') ylabel('mm')

axis([-400 500 -100 600]); %5.曲柄滑块机构运动仿真 figure(3)

m=moviein(20); j=0;

for n1=1:5:360 j=j+1; clf; x(1)=0; y(1)=0;

x(2)=l1*cos(n1*hd); y(2)=l1*sin(n1*hd);

x(3)=x(2)+l2*cos(theta2(n1)); y(3)=y(2)+l2*sin(theta2(n1)); x(4)=-a; y(4)=b;

x(5)=2*x(4)-x(3); y(5)=2*y(4)-y(3);

x(6)=x(5)+l4*cos(theta4(45)); y(6)=b+c;

x(7)=x(6)+40; y(7)=y(6)+20; x(8)=x(6)+40; y(8)=y(6)-20;

x(9)=x(6)-40; y(9)=y(6)-20; x(10)=x(6)-40; y(10)=y(6)+20; x(11)=x(6)+40; y(11)=y(6)+20; i=1:6;

plot(x(i),y(i)); grid on;hold on; i=7:11;

plot(x(i),y(i));

plot(x(1),y(1),'o'); plot(x(2),y(2),'o'); plot(x(3),y(3),'o'); plot(x(4),y(4),'o'); plot(x(5),y(5),'o'); plot(x(6),y(6),'o');

axis([-400 500 -100 600]); title('曲柄滑块机构仿真'); xlabel('mm'); ylabel('mm'); m(j)=getframe; end

movie(m);

子程序文件

function[theta,omega,OMEGA,alpha,ALPHA,s5,v5,a5]=crank_rocker(theta1,omega1,alpha1,l1,l2,lcd,lde,l4,a,b,c) %1.计算从动件的角位移和滑块5的位移

L1=sqrt((a+l1*cos(theta1))*(a+l1*cos(theta1))+(b-l1*sin(theta1))*(b-l1*sin(theta1)));

beta1=acos((L1*L1+l2*l2-lcd*lcd)/(2*L1*l2));

beta2=atan((a+l1*cos(theta1))/(b-l1*sin(theta1))); theta2=pi/2+beta1+beta2;

theta3=atan(-b/(a-(-l2*cos(theta2)-l1*cos(theta1)))); theta4=asin((c-lde*sin(theta3))/l4); theta=[theta1;theta2;theta3;theta4]; s5=l4*cos(theta4)+lde*cos(theta3); %2.计算从动件的角速度和滑块5的线速度

A=[-l2*sin(theta2),-lcd*sin(theta3);-l2*cos(theta2),-lcd*cos(theta3)];

B=[l1*sin(theta1);l1*cos(theta1)]; omega=A\\(omega1*B);

omega2=omega(1); omega3=omega(2);

C=[l4*sin(theta4),1;-l4*cos(theta4),0]; D=[-lde*sin(theta3);lde*cos(theta3)]; OMEGA=C\\(omega3*D); omega4=OMEGA(1); v5=OMEGA(2);

%3.计算从动件的角加速度和滑块5的加速度 A=[-l2*sin(theta2),lcd*sin(theta3); l2*cos(theta2),lcd*cos(theta3)];

At=[omega2*l2*cos(theta2),omega3*lcd*cos(theta3); omega2*l2*sin(theta2),omega3*lcd*sin(theta3)]; B=[omega1*l1*cos(theta1); omega1*l1*sin(theta1)]; alpha=A\\(At*omega+omega1*B); alpha2=alpha(1); alpha3=alpha(2);

C=[l4*sin(theta4),1; -l4*cos(theta4),0];

D=[-lde*sin(theta3),-omega3*lde*cos(theta3); lde*cos(theta3),-omega3*lde*sin(theta3)]; Ct=[omega4*l4*cos(theta4),0; omega4*l4*sin(theta4),0]; Dt=[alpha3;omega3];

ALPHA=C\\(D*Dt-Ct*OMEGA); alpha4=ALPHA(1); a5=ALPHA(2);

4、计算结果

下图为六杆机构的运动线图：