ETD

• acc grid
• actuators
• fem analysis
• ion thruster
• piezoelectric
• stack

This thesis aims to describe, analyze and study the real efficiency of one possible type of control system, in particular the thrust vectoring system using piezoelectric stack actuators that move the accelerator grid of a gridded ion thruster. Initially, the piezoelectric materials are described both in terms of their chemical-physical properties and in terms of the constitutive and motion equations that govern them. In the same way the principle of working of the Gridded Ion Thruster is described, paying particular attention to the importance of the acceleration grid (ACC grid) and what consequences it can have on the exhaust ion flux moving it even by a few micrometers. It also describes a particular analysis carried out on the grid used to create a model of the same more simplified, from a geometric point of view, to be used in the FEM analysis. The piezoelectric actuators are then described, focusing on the piezoelectric stacks and analyzing their behavior when subjected to pre-established differences in potential. Finally, a representative model of the grid - piezoelectric stack system is described, on which static structural analysis, thermal analysis and modal analysis are carried out using a FEM analysis software.