me2046 hw4

ME_2046/HW4/hw4.py

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+import sympy as sm
+import numpy as np
+import matplotlib.pyplot as plt
+
+sm.init_printing()
+
+print("PROBLEM 1:")
+print("part a:")
+s, z, t = sm.symbols("s z t")
+
+J, B, RHO, RADIUS, L, RESIST, T = sm.symbols(
+    "J, B, rho,  r,  L,  R, T", Real=True, Positive=True
+)
+K_T, K_B = sm.symbols("K_T,  K_b")
+
+# loop gain
+Loop_Gain = K_T * 1 / (J * s + B)
+
+# transfer function from motor current command to linear displacement (ignoring feedback)
+X_over_I = Loop_Gain * RHO / s * RADIUS
+sm.pprint(X_over_I)
+X_over_I = X_over_I.expand().simplify()
+sm.pprint(X_over_I)
+
+print("part b:")
+# recall ZOH_eq
+# G(z) = (1-z**-1) Z{L**-1{G(s)/s}}
+print("Finding inverse laplace of G/s")
+G_s = X_over_I
+sm.pprint(G_s / s)
+g_t = sm.inverse_laplace_transform(G_s / s, s, t)
+sm.pprint(g_t.expand())
+
+# make z substitution subs
+
+G_z = (
+    K_T * T * RADIUS * RHO / B * (z / (z - 1) ** 2)
+    - J * K_T * RADIUS * RHO / B**2
+    + J * K_T * RADIUS * RHO / B**2 * (z / (z - sm.exp(-B / J * T)))
+)
+
+sm.pprint(G_z.simplify())
+
+# part c was on the board
+print("part c")
+F = sm.Matrix([[0, RHO], [0, -B / J]])
+G = sm.Matrix([0, K_T / J])
+
+# part d
+print("part d")
+A = sm.exp(F * T)
+B = sm.integrate(A, (T, 0, T))
+sm.pprint(F)
+sm.pprint(G)
+sm.pprint(A)
+sm.pprint(B)

NUCE_2113/lab6/quick_maths.py

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+print("Experiment 6.1\n")
+measured_activity = 5.2e-6  # curies
+elapsed_time = 193.92  # s
+sigma_u1 = 35331  # counts
+background_time = 193.94  # s
+sigma_b = 558  # counts
+
+R = sigma_u1 / elapsed_time - sigma_b / background_time
+print(f"R: {R:.3e} counts / s")
+print(f"R: {R/3.7e10*1e6:.3e} microcurie")
+eps_ip = 0.101  # from figure 6.2
+f = 0.6617
+
+d = 100  # mm
+r = 38 / 2  # mm
+
+G = r**2 / 4 / d**2
+
+A = R / eps_ip / G / f
+
+print(f"G: {G:.3e}")
+print(f"A: {A:.3e} decays / s")
+print(f"A: {A/3.7e10*1e6:.3e} microcurie")
+
+A = 4.5 * 3.7e10 / 1e6
+eps_ip_est = R / A / G / f
+print(f"eps_ips: {eps_ip_est:.3e}")
+
+sigma_u1 = [10122, 11763, 14464, 17476, 22073, 28268, 38084]
+sigma_b = 130
+d = [100, 90, 80, 70, 60, 50, 40]
+t = 60  # s
+
+import numpy as np
+
+n = len(sigma_u1)
+R = np.empty(n)
+G = np.empty(n)
+eps_ip = np.empty(n)
+
+for i, value in enumerate(sigma_u1):
+    print(i, value)
+    R[i] = (value - sigma_b) / t
+    G[i] = r**2 / 4 / d[i] ** 2
+    eps_ip[i] = R[i] / A / G[i] / f
+
+print("R")
+print(R.transpose())
+print("G")
+print(G.transpose())
+print("eps_ip")
+print(eps_ip.transpose())
+
+import matplotlib.pyplot as plt
+
+plt.plot(d, eps_ip, ".b")
+plt.xlabel("Distance [mm]")
+plt.ylabel("$\epsilon_{ip}$")
+plt.grid("both")
+plt.savefig("exercise6_4.png")
+plt.show()