I would like to simulate the response of a cantilever energy harvester under harmonic base excitation from an electrodynamic shaker. I would like to carry out a damped transient structural-piezoelectric analysis to simulate the steady-state response of the energy harvester under a constant peak acceleration sinusoidal excitation followed by its free vibration response after the excitation from the electrodynamic shaker is stopped. 

I have attached a .txt file of my current input commands for reference. I've managed to set-up the elements, material properties, geometry, mesh, clamped boundary conditions and electrical boundary conditions, and transient analysis options. However, what I need help with is specifying the load steps and sinusoidal excitation boundary condition. The harmonic base excitation has a constant peak acceleration of 1g and excitation frequency of 44.29 Hz and is in the Z-direction. 

I would like help with the following:

  • how to apply the constant peak acceleration harmonic base excitation
  • how best to simulate the switching off of the electrodynamic shaker until the shaker is at rest and measuring the free vibration response of the cantilever 

Any help would be greatly appreciated. Thank you.