Padula-Visioli tuning algorithm for a FOPID controller

Algorithm was proposed by Fabrizio Padula and Antonio Visioli in:
[1] F. Padula and A. Visioli, "Tuning rules for optimal PID and fractional-order PID controllers," J. Process Control, vol. 21, no. 1, pp. 69–81, Jan. 2011.

Requirements:
FOTF toolbox
Parameters:
K - FOPDT gain
T - FOPDT time constant
L - FOPDT dead time
Output:
SP14 - 5-element vector of coefficients [K_P, K_I, K_D, \mu, \nu, N] for the Set point task, M_1=1.4
SP20 - coefficients for the Set point task, M_2=2.0
LD14 - coefficients for the Load disturbance rejection task, M_1=1.4
LD20 - coefficients for the Load disturbance rejection task, M_2=2.0
GconSP14 - fractional-order transfer function (FOTF) of the FOPID controller based on SP14 coefficients
GconSP20 - FOTF of the FOPID based on SP20 coefficients
GconLD14 - FOTF of the FOPID based on LD14 coefficients
GconLD20 - FOTF of the FOPID based on LD20 coefficients

Implemented by: Mariusz Matusiak <mmatusiak@iis.p.lodz.pl>