Table 1: System physical parameters.

J1,J2 0.185kg.m2
Jm 0.028kg.m2
b1,b2 1.2N.m.s/rad
bm 1.3N.m.s/rad
k [560 + 2sin(πt)]N.m/rad
c [0.15 + 0.01sin(πt)]N.m/rad
α 0.5rad