2.连杆机构运动分析流程
(1)首先建立坐标系:
(2)划分基本杆组和自由度计算:
活动构件数n=5,PL=7,PH=0,则机构的自由度:
F=3n-2PL-PH=3×5-2×7-0=1
AB(Ⅰ级杆组):
BCD(RRPⅡ级杆组):
DE(RPRⅡ级杆组):
(3)数学方法解出D位置与夹角Ψ:
运动副B的位置坐标:
xB=lABcosφ
yB=lABsinφ
用B点位置方程求C点,进而求得D点位置:
xD=lAC+lCD’
yD=(lDC/lBC)*yB’
最后求出杆件5与x轴夹角Ψ:
tanΨ=lDD’/lD’E
Ψ=arctanlDD’/lD’E
(4)matlab程序与输出图像:
%下面是套筒D的轨迹程序
clear;
clf;
w=10;f1=0:
(pi/1000):
1.12575;
t1=f1./w;
xb1=100.*cos(f1);
yb1=100.*sin(f1);
xd1=xb1+2*sqrt(200.^2-yb1.^2);
yd1=0-yb1;
lde1=xd1-400;
ldd1=yb1;
p1=atan(ldd1./lde1);
theta1=0-p1;
f2=1.12575:
(pi/1000):
pi;
t2=f2./w;
xb2=100.*cos(f2);
yb2=100.*sin(f2);
xd2=xb2+2*sqrt(200.^2-yb2.^2);
yd2=-yb2;
lde2=400-xd2;
ldd2=yb2;
p2=atan(ldd2./lde2);
theta2=p2-pi;
f3=pi:
(pi/1000):
2*pi-1.12575;
t3=f3./w;
xb3=100.*cos(f3);
yb3=100.*sin(f3);
xd3=xb3+2*sqrt(200.^2-yb3.^2);
yd3=-yb3;
lde3=400-xd3;
ldd3=yd3;
p3=atan(ldd3./lde3);
theta3=-p3-pi;
f4=2*pi-1.12574:
(pi/1000):
2*pi;
t4=f4./w;
xb4=100.*cos(f4);
yb4=100.*sin(f4);
xd4=xb4+2*sqrt(200.^2-yb4.^2);
yd4=-yb4;
lde4=xd4-400;
ldd4=yd4;
p4=atan(ldd4./lde4);
theta4=p4-2*pi;plot(xd1,yd1,'b',xd2,yd2,'b',xd3,yd3,'b',xd4,yd4,'b');
xlabel('X位移(mm)');
ylabel('Y位移(mm)');
title('套筒D轨迹曲线');
gridon;
杆5角位移:
%下面是杆5角位移程序
clear;
clf;
w=10;f1=0:
(pi/1000):
1.12575;
t1=f1./w;
xb1=100.*cos(f1);
yb1=100.*sin(f1);
xd1=xb1+2*sqrt(200.^2-yb1.^2);
yd1=0-yb1;
lde1=xd1-400;
ldd1=yb1;
p1=atan(ldd1./lde1);
theta1=0-p1;
f2=1.12575:
(pi/1000):
pi;
t2=f2./w;
xb2=100.*cos(f2);
yb2=100.*sin(f2);
xd2=xb2+2*sqrt(200.^2-yb2.^2);
yd2=-yb2;
lde2=400-xd2;
ldd2=yb2;
p2=atan(ldd2./lde2);
theta2=p2-pi;
f3=pi:
(pi/1000):
2*pi-1.12575;
t3=f3./w;
xb3=100.*cos(f3);
yb3=100.*sin(f3);
xd3=xb3+2*sqrt(200.^2-yb3.^2);
yd3=-yb3;
lde3=400-xd3;
ldd3=yd3;
p3=atan(ldd3./lde3);
theta3=-p3-pi;
f4=2*pi-1.12574:
(pi/1000):
2*pi;
t4=f4./w;
xb4=100.*cos(f4);
yb4=100.*sin(f4);
xd4=xb4+2*sqrt(200.^2-yb4.^2);
yd4=-yb4;
lde4=xd4-400;
ldd4=yd4;
p4=atan(ldd4./lde4);
theta4=p4-2*pi;plot(t1,theta1,'b',t2,theta2,'b',t3,theta3,'b',t4,theta4,'b');
xlabel('时间(s)');
ylabel('角度(rad)');
title('构件5角位移');
gridon;
杆5角速度:
%下面是角速度程序
clear;
clf;
f1=0:
(pi/1000):
1.12575;
w=10;
t1=f1./w;
xb1=100.*cos(f1);
yb1=100.*sin(f1);
xd1=xb1+2*sqrt(200.^2-yb1.^2);
yd1=0-yb1;
lde1=xd1-400;
ldd1=yb1;
p1=atan(ldd1./lde1);
theta1=0-p1;
omega1=diff(theta1,1);
t1(30)=[];
f2=1.12575:
(pi/1000):
pi;
w=10;
t2=f2./w;
xb2=100.*cos(f2);
yb2=100.*sin(f2);
xd2=xb2+2*sqrt(200.^2-yb2.^2);
yd2=-yb2;
lde2=400-xd2;
ldd2=yb2;
p2=atan(ldd2./lde2);
theta2=p2-pi;
omega2=diff(theta2,1);
t2(60)=[];
f3=pi:
(pi/1000):
2*pi-1.12575;
t3=f3./w;
xb3=100.*cos(f3);
yb3=100.*sin(f3);
xd3=xb3+2*sqrt(200.^2-yb3.^2);
yd3=-yb3;
lde3=400-xd3;
ldd3=yd3;
p3=atan(ldd3./lde3);
theta3=-p3-pi;
omega3=diff(theta3,1);
t3(60)=[];
f4=2*pi-1.12574:
(pi/1000):
2*pi;
t4=f4./w;
xb4=100.*cos(f4);
yb4=100.*sin(f4);
xd4=xb4+2*sqrt(200.^2-yb4.^2);
yd4=-yb4;
lde4=xd4-400;
ldd4=yd4;
p4=atan(ldd4./lde4);
theta4=p4-2*pi;
omega4=diff(theta4,1);
t4(30)=[];
plot(t1,omega1,'r',t2,omega2,'r',t3,omega3,'r',t4,omega4,'r');
xlabel('时间(s)');ylabel('角速度(rad)');
title('构件5角速度');
gridon;
角加速度
%下面是杆5的角加速度程序
clear;
clf;
f1=0:
(pi/1000):
1.12575;
w=10;
t1=f1./w;
xb1=100.*cos(f1);
yb1=100.*sin(f1);
xd1=xb1+2*sqrt(200.^2-yb1.^2);
yd1=0-yb1;
lde1=xd1-400;
ldd1=yb1;
p1=atan(ldd1./lde1);
theta1=0-p1;
alpha1=diff(theta1,2);
t1(60)=[];t1
(1)=[];
w=10;
f2=1.12575:
(pi/1000):
pi;
t2=f2./w;
xb2=100.*cos(f2);
yb2=100.*sin(f2);
xd2=xb2+2*sqrt(200.^2-yb2.^2);
yd2=-yb2;
lde2=400-xd2;
ldd2=yb2;
p2=atan(ldd2./lde2);
theta2=p2-pi;
alpha2=diff(theta2,2);
t2(200)=[];t2
(1)=[];
f3=pi:
(pi/1000):
2*pi-1.12575;
t3=f3./w;
xb3=100.*cos(f3);
yb3=100.*sin(f3);
xd3=xb3+2*sqrt(200.^2-yb3.^2);
yd3=-yb3;
lde3=400-xd3;
ldd3=yd3;
p3=atan(ldd3./lde3);
theta3=-p3-pi;
alpha3=diff(theta3,2);
t3(200)=[];t3
(1)=[];
f4=2*pi-1.12574:
(pi/1000):
2*pi;
t4=f4./w;
xb4=100.*cos(f4);
yb4=100.*sin(f4);
xd4=xb4+2*sqrt(200.^2-yb4.^2);
yd4=-yb4;
lde4=xd4-400;
ldd4=yd4;
p4=atan(ldd4./lde4);
theta4=p4-2*pi;
alpha4=diff(theta4,2);
t4(60)=[];t4
(1)=[];
plot(t1,alpha1,'r',t2,alpha2,'r',t3,alpha3,'r',t4,alpha4,'r');
xlabel('时间(s)');ylabel('角加速度(rad)');
title('杆5的角加速度');
gridon;