Melnikov method for subharmonic orbits
The software below is the one used to compute the numerical results
presented in
The Melnikov method and subharmonic orbits in a piecewisesmooth
system . See the paper for details on the system and
parameters definition.
Download
subharmonic_melnikov.tar.gz
List of files, routines and their goals

system.dat contains system parameters: n m y0 t0 delta rho
omega, where
 nT is the period of the desired periodic orbit

2*m the number of impacts

y0 is the initial sead for the Newton method, such that (0,y0) is the
initial condition for an nT period orbit of the
unperturbed system

t0 is the zero of the modified Melnikov function

delta is perturbation parameter

rho is the ratio between the forcing and the restitution coefficient
omega is the frequency of the forcing

find_nm_ini_cond computes the initial conditions, (x0,t0) for
a periodic orbit whose parameters are given in system.dat

solve_wt0 computes a zero of the Melnikov function

find_delta_max.sh and follow_orbit.sh perform a
continuation method by increasing delta until the periodic orbit
bifurcates

find_existence_regions.sh computes the existence region for an
n,mperiodic orbit in the epsilonr parameter space