用matlab分析四杆机构

1、首先创建函数 FoutBarPosition ，函数 fsolve 通过他确定 。function t=fourbarposition(th,th2,L2,L3,L4,L1)t=L2*cos(th2)+L3*cos(th(1)-L4*cos(th(2)-L1; L2*sin(th2)+L3*sin(th(1)-L4*sin(th(2);主程序如下：disp ' * * *平面四杆机构的运动分析L1=304.8;L2=101.6;L3=254.0;L4=177.8;% 给定已知量，各杆长 L1,L2,L3,L4th2=0:1/6:2*pi;% 曲柄输入角度从 0 至 360 度，步长为

2、pi/6th34=zeros(length(th2),2);%建立一个 N行2列的零矩阵，第一列存放options=optimset('display','off');%0 _3 ,第二列存放 0 _3for m=1:length(th2)%建立for循环，求解 0 _3 0 _4th34(m,:)=fsolve('fourbarposition',11,%调用fsove函数求解关于 0 _3 0 _4options,th2(m),L2,L3,L4,L1);% 的非线性超越方程，结果保存在 th34 中endy=L2*sin(th2)+L3*si

3、n(th34(:,1)');% 连杆 3 的 D 端点 Y 坐标值x=L2*cos(th2)+L3*cos(th34(:,1)');% 连杆 3 的 D 端点 X 坐标值xx=L2*cos(th2);% 连杆 3 的 C 端点 X 坐标值yy=L2*sin(th2);% 连杆 3 的 C 端点 Y 坐标值figure(1)plot(x;xx,y;yy,'k',0 L1,0 0,%绘制连杆3的几个位置点'k-A',x,y,'ko',xx,yy,'ks') title（' 连杆 3 的几个位置点 '）

4、xlabel(' 水平方向 ') ylabel(' 垂直方向 ') axis equal %XY 坐标均衡th2=0:2/72:2*pi;% 重新细分曲柄输入角度 0 _2，步长为 5 度th34=zeros(length(th2),2);options=optimset('display','off');for m=1:length(th2)th34(m,:)=fsolve('fourbarposition',1 1, options,th2(m),L2,L3,L4,L1);endfigure(2) plot(t

5、h2*180/pi,th34(:,1)*180/pi,plot(th2*180/pi,th34(:,1),th2*180/pi,th34(:,2) 图%绘制连杆 3的角位移关于曲柄 2 的角位移th2*180/pi,th34(:,2)*180/pi)% 绘制摇杆 4 的角位移关于曲柄 2 的角位移图axis(0 360 0 170) % 确定 XY 边界值grid % 图形加网格xlabel(' 主动件转角 theta_2( 度 )') ylabel(' 从动件角位移 (度 )') title(' 角位移线图 ') text(120,120,&#

6、39; 摇杆 4 角位移 ') text(150,40,' 连杆 3 角位移 ') w2=250; % 设定曲柄角速度for i=1:length(th2)A=- L3*sin(th34(i,1) L4*sin(th34(i,2);L3*cos(th34(i,1) -L4*cos(th34(i,2);B=w2*L2*sin(th2(i); -w2*L2*cos(th2(i);w=inv(A)*B;w3(i)=w(1);w4(i)=w(2);end figure(3)plot(th2*180/pi,w3,th2*180/pi,w4);% 绘制角速度线图axis(0 360

7、 -175 200) text(50,160,' 摇杆 4 角速度 (omega_4)') text(220,130,' 连杆 3 角速度 (omega_3)')grid xlabel(' 主动件转角 theta_2( 度 )') ylabelC 从动件角速度(rad'cdot s-l)') title（' 角速度线图 '） for i=1:length(th2)C=-L3*sin(th34(i,1) L4*sin(th34(i,2);L3*cos(th34(i,1) -L4*cos(th34(i,2);D=w2A

8、2*L2*cos(th2(i)+w3(i)A2*L3*cos(th34(i,1)-w4(i)A2*L4*cos(th34(i,2);.w2A2*L2*si n( th2(i)+w3(i)2*L3*s in (th34(i,1)-w4(i)A2*L4*si n( th34(i,2);a=inv(C)*D;a3(i)=a(1);a4(i)=a(2);end%绘制角加速度线图figure(4) plot(th2*180/pi,a3,th2*180/pi,a4);axis(0 360 -70000 65000) text(50,50000,' 摇杆 4 角加速度 (alpha_4)')

9、 text(220,12000,' 连杆 3 角加速度 (alpha_3)')gridxlabel（' 从动件角加速度')ylabel（' 从动件角加速度(radcdot s-2)')title（' 角加速度线图 '）disp ' 曲柄转角连杆转角-摇杆转角 -连杆角速度 -摇杆角速度 -连杆加速度 -摇杆加速度 'ydcs=th2'*180/pi,th34(:,1)*180/pi,th34(:,2)*180/pi,w3',w4',a3',a4'disp(ydcs)>&

10、gt;* * * 平面四杆机构的运动分析曲柄转角 连杆转角 -摇杆转角 -连杆角速度 -摇杆角速度 -连杆加速度 -摇杆加速度 1.0e+004 *0 0.00440.0097 -0.0125-0.0125-0.54784.84580.00050.00420.0094-0.0126-0.01070.23005.56300.00100.00390.0092-0.0124-0.00860.89466.05200.00150.00370.0091-0.0119-0.00651.41436.29820.00200.00340.0090-0.0114-0.00431.78016.31740.00250.

11、00320.0089-0.0107-0.00212.00276.14670.00300.00300.0089-0.01000.00002.10465.83390.00350.00280.0089-0.00930.00202.11345.42720.00400.00260.0090-0.00850.00382.05664.96870.00450.00250.0091-0.00780.00541.95784.49180.00500.00230.0092-0.00720.00691.83564.01980.00550.00220.0093-0.00650.00821.70403.56800.0060

12、0.00210.0095-0.00600.00941.57253.14500.00650.00190.0097-0.00550.01041.44742.75450.00700.00180.0099-0.00500.01131.33282.39680.00750.00170.0102-0.00450.01211.23072.07020.00800.00170.0104-0.00410.01281.14251.77160.00850.00160.0107-0.00370.01341.06871.49710.00900.00150.0110-0.00340.01381.00951.24260.009

13、50.00140.0112-0.00300.01420.96531.00350.01000.00140.0115-0.00270.01450.93640.77520.01050.00130.0118-0.00240.01480.92320.55300.01100.00130.0121-0.00200.01490.92690.33190.01150.00130.0124-0.00170.01500.94850.10690.01200.00120.0127-0.00140.01500.9899-0.12760.01250.00120.0130-0.00100.01491.0530-0.37730.

14、01300.00120.0133-0.00060.01471.1404-0.64810.01350.00120.0136-0.00020.01451.2544-0.94550.01400.00120.01390.00020.01411.3967-1.27430.01450.00120.01420.00080.01361.5677-1.63680.01500.00120.01440.00130.01291.7648-2.03140.01550.00120.01470.00200.01211.9807-2.44950.01600.00130.01490.00270.01122.2018-2.873

15、50.01650.00130.01510.00350.01012.4071-3.27540.01700.00140.01530.00440.00892.5697-3.61860.01750.00150.01550.00530.00762.6616-3.86500.01800.00160.01560.00630.00632.6609-3.98490.01850.00180.01570.00720.00492.5591-3.96740.01900.00190.01580.00800.00352.3638-3.82440.01950.00210.01590.00880.00222.0959-3.58

16、660.02000.00230.01590.00950.00101.7823-3.29310.02050.00250.01590.0100-0.00011.4487-2.98150.02100.00270.01590.0105-0.00111.1152-2.68090.02150.00290.01590.0108-0.00200.7942-2.41030.02200.00310.01580.0111-0.00280.4916-2.17940.02250.00330.01580.0112-0.00350.2086-1.99130.02300.00360.01570.0112-0.0042-0.0

17、565-1.84500.02350.00380.01560.0111-0.0048-0.3071-1.73750.02400.00400.01550.0110-0.0054-0.5475-1.66500.02450.00420.01540.0108-0.0060-0.7817-1.62330.02500.00440.01530.0104-0.0065-1.0139-1.60890.02550.00460.01510.0100-0.0071-1.2479-1.61810.02600.00480.01500.0096-0.0077-1.4868-1.64800.02650.00500.01480.

18、0090-0.0082-1.7336-1.69550.02700.00520.01460.0084-0.0088-1.9905-1.75740.02750.00540.01450.0076-0.0095-2.2588-1.83040.02800.00550.01430.0068-0.0101-2.5391-1.91000.02850.00560.01410.0058-0.0108-2.8305-1.99100.02900.00570.01380.0048-0.0115-3.1300-2.06600.02950.00580.01360.0037-0.0122-3.4326-2.12550.03000.00590.01330.0024-0.0130-3.7297-2.15720.03050.00590.01310.0011-0.0137-4.0091-2.14510.03100.00590.0128-0.0004-0.0145-4.2538-2.06960.03150.00590.0125-0.0019-0.0152-4.4419-1.90790.03200.0