def GetBatt(S):

    global nominal_thrust
    B = S.battery_remaining
    # coefficients for fourth order fit
    # determined 11 May 2015 by Spencer Maughan and Ishmaal Erekson
    c0 =  0.491674747062374
    c1 = -0.024809293286468
    c2 =  0.000662710609466
    c3 = -0.000008160593348
    c4 =  0.000000033699651
    nominal_thrust = c0+c1*B+c2*B**2+c3*B**3+c4*B**4 

    #============================#
    #    Get Controller Status   #
    #============================#