内容发布更新时间 : 2025/1/1 6:18:31星期一 下面是文章的全部内容请认真阅读。

【14】

>> t=[-1:0.001:-0.2,-0.1999:0.0001:0.1999,0.2:0.001:1]; y=sin(1./t); plot(t,y);

grid on;

10.80.60.40.20-0.2-0.4-0.6-0.8-1-1-0.8-0.6-0.4-0.200.20.40.60.81

【15】

(1) >> t=-2*pi:0.01:2*pi; r=1.0013*t.^2;

polar(t,r);axis('square')

90120 30150 20 1018030 40600210330240270300

11

(2) >> t=-2*pi:0.001:2*pi; r=cos(7*t/2);

polar(t,r);axis('square')

90120 0.8 0.6150 0.4 0.2180030 160210330240270300

(3) >> t=-2*pi:0.001:2*pi; r=sin(t)./t;

polar(t,r);axis('square')

90120 0.8 0.6150 0.4 0.2180030 16021033090240270300 260 1.5 130120

(4) >> t=-2*pi:0.001:2*pi; r=1-cos(7*t).^3; polar(t,r);axis('square')

150 0.5180021033024027030012

【17】

(1)z=xy

>> [x,y]=meshgrid(-3:0.01:3,-3:0.01:3); z=x.*y; mesh(x,y,z);

>> contour3(x,y,z,50);

1050-5-1020-2-3-2-10123

13

(1)z=sin(xy)

>> [x,y]=meshgrid(-3:0.01:3,-3:0.01:3); z=sin(x.*y); mesh(x,y,z);

>> contour3(x,y,z,50);

10.50-0.5-120-2-3-2-10123

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第3章 线性控制系统的数学模型

【1】

(1) >> s=tf('s');

G=(s^2+5*s+6)/(((s+1)^2+1)*(s+2)*(s+4)) Transfer function:

s^2 + 5 s + 6 --------------------------------

s^4 + 8 s^3 + 22 s^2 + 28 s + 16

(2) >> z=tf('z',0.1);

H=5*(z-0.2)^2/(z*(z-0.4)*(z-1)*(z-0.9)+0.6) Transfer function:

5 z^2 - 2 z + 0.2 ---------------------------------------

z^4 - 2.3 z^3 + 1.66 z^2 - 0.36 z + 0.6 Sampling time (seconds): 0.1

【2】

(1)该方程的数学模型

>> num=[6 4 2 2];den=[1 10 32 32]; G=tf(num,den) Transfer function: 6 s^3 + 4 s^2 + 2 s + 2 ------------------------

s^3 + 10 s^2 + 32 s + 32

(2)该模型的零极点模型 >> G=zpk(G) Zero/pole/gain:

6 (s+0.7839) (s^2 - 0.1172s + 0.4252) ------------------------------------- (s+4)^2 (s+2)

(3)由微分方程模型可以直接写出系统的传递函数模型

15