Trying to recall my automatic driving class

gistfile1.txt

    A  A           B   C            D  D           E    E           F
e ---->--->(1+k_1)--->+--->(z^-1/2)--->--->(1+k_2)--->+--->(z^-1/2)---> y
      |              /\               |              /\              |
      |               |               |               |              |
      |               |               |               |              |
     \/              (-k_1)          \/              (-k_2)          |
    k_1              /\              k_2             /\              |
      |               |               |               |              |
      |               |               |               |              |
      |               |               |               |              |
     \/               |              \/               |              |
<-----+<---(1-k_1)<---<---(z^-1/2)<---+<---(1-k_2)<---<---(z^-1/2)<---
    Z    Y          X   X            W   V          U   U             T



A = e
B = (1+k_1) * e
C = (1+k_1)*e - k_1 * ((1-k_2)*y[i-2] + k_2D)
    (1+k_1)e[i-1] - k_1(1-k_2)y[i-2]
D = --------------------------------
            1 - k_1*k_2
E = (1+k_2)*D
F = y
T = y
U = y[i-1]
V = (1-k_2) * y[i-1] - delay count == 1
W = (1-k_2)*y[i-1] + k_2*D
X = (1-k_2) * y[i-2] + k_2*D
Y = (1-k_1)((1-k_2)y[i-2] + k_2D)
Z = (1-k_1)((1-k_2)y[i-2] + k_2D) + k_1*e


    (1 - k_2) * y[i-2] + k_2 * (1+k_1) * e[i-1]
X = ---------------------------------------------------
                    1 + k_1*k_2