CH08_SEC01_CruiseControl.ipynb

Kernel: Python 3

import numpy as np
import matplotlib.pyplot as plt
from matplotlib import rcParams

rcParams.update({'font.size': 18})
plt.rcParams['figure.figsize'] = [12, 12]

t = np.arange(0,10,0.01)   # time

wr = 60 * np.ones_like(t)  # reference speed
d = 10*np.sin(np.pi*t)     # disturbance

aModel = 1                 # y = aModel*u
aTrue = 0.5                # y = aTrue*u

uOL = wr/aModel            # Open-loop u based on model
yOL = aTrue*uOL + d        # Open-loop response

K = 50                     # control gain, u=K(wr-y)
yCL = (aTrue*K/(1+aTrue*K))*wr + d/(1+aTrue*K)

plt.plot(t,wr,'k',linewidth=2,label='Reference')
plt.plot(t,d,'k--',linewidth=1.5,label='Disturbance')
plt.plot(t,yOL,'r',linewidth=1.5,label='Open Loop')
plt.plot(t,yCL,'b',linewidth=1.5,label='Closed Loop')

plt.xlabel('Time')
plt.ylabel('Speed')

plt.legend(loc="upper left", bbox_to_anchor=(1,1))
plt.show()