rrranalysis.m

用于机械原理课程中对RRR结构的运动分析

function [phi2,phi3,omega2,omega3,epsilon2,epsilon3,xC,yC,vCx,vCy ,aCx,aCy] = RRRAnalysis(  xB,yB,xD,yD,vBx,vBy,vDx,vDy,aBx,aBy,aDx,aDy,l2,l3,M )
%已知两外副B,D的位置坐标(xB,yB),(xD,yD),速度vB,vD，加速度aB,aD,杆长l2,l3
%输出构件2，3的角位置phi2.phi3,角速度omega2,omega3，角加速度epsilon2,epsilon3，以及其内副C的位置坐标(xC
%,yC),速度vC和加速度aC
d=sqrt((xD-xB).^2+(yD-yB).^2);
sigma=atan((yD-yB)./(xD-xB));
gama=acos((d.^2+l2^2-l3^2)./(2*l2*d));
phi2=sigma+M*gama;
xC=xB+l2.*cos(phi2);
yC=yB+l2.*sin(phi2);
phi3=atan((yC-yD)./(xC-xD));
omega2=((vDx-vBx).*(xC-xD)+(vDy-vBy).*(yC-yD))./((yC-yD).*(xC-xB)-(yC-yB).*(xC-xD));
omega3=((vDx-vBx).*(xC-xB)+(vDy-vBy).*(yC-yB))./((yC-yD).*(xC-xB)-(yC-yB).*(xC-xD));
vCx=vBx-omega2.*(yC-yB);
vCy=vBy+omega2.*(xC-xB);
E=aDx-aBx+omega2.^2.*(xC-xB)-omega3.^2.*(xC-xD);
F=aDy-aBy+omega2.^2.*(yC-yB)-omega3.^2.*(yC-yD);
epsilon2=(E.*(xC-xD)+F.*(yC-yD))./((xC-xB).*(yC-yD)-(xC-xD).*(yC-yB));
epsilon3=(E.*(xC-xB)+F.*(yC-yB))./((xC-xB).*(yC-yD)-(xC-xD).*(yC-yB));
aCx=aBx-omega2.^2.*(xC-xB)-epsilon2.*(yC-yB);
aCy=aBy-omega2.^2.*(yC-yB)+epsilon2.*(xC-xB);
end