├── Control library.py
└── README.md


/Control library.py:
--------------------------------------------------------------------------------
 1 | import control as ct
 2 | import matplotlib.pyplot as plt
 3 | 
 4 | s = ct.TransferFunction.s
 5 | 
 6 | # System parameters
 7 | m = 0.5
 8 | l = 1
 9 | k = 0.5
10 | J = m*l*l
11 | g = 9.81
12 | 
13 | # Non-linear system:
14 | # tau = J*ddtheta + k*dtheta + m*g*l*sin(theta)
15 | 
16 | # Linearised system in theta = pi/2:
17 | # tau = J*ddtheta + k*dtheta - m*g*l*theta
18 | 
19 | # Transfer function
20 | P = 1/(J*s**2 + k*s - m*g*l)
21 | 
22 | # Plot root-locus of P
23 | plt.figure()
24 | ct.root_locus(P)
25 | 
26 | # Controller transfer function - lead-lag
27 | Tc = 0.2
28 | z = -3
29 | K = 2
30 | C = K*(s-z)/(Tc*s+1)
31 | 
32 | # Close-loop transfer function
33 | G = ct.feedback(C*P, 1)
34 | 
35 | # Plot root-locus of C*P
36 | plt.figure()
37 | ct.root_locus(C*P)
38 | 
39 | # Plot Nyquist diagram
40 | plt.figure()
41 | ct.nyquist_plot(C*P)
42 | 
43 | # Ideal step response
44 | t, yout = ct.step_response(G)
45 | plt.figure()
46 | plt.plot(t, yout)
47 | plt.grid()
48 | plt.xlabel("Time [s]")
49 | 
50 | # Show plots
51 | plt.show()


--------------------------------------------------------------------------------
/README.md:
--------------------------------------------------------------------------------
1 | # Python-Control-Library
2 | An example of how to use the Python Control Library.
3 | 
4 | Code created to support a Linkedin post. Follow me on Linkedin! https://www.linkedin.com/in/simone-bertoni-control-eng/
5 | 


--------------------------------------------------------------------------------