27 oct
27/10/2017 09:30


Soutenance de thèse : Fabien DUBOIS

Tribological and vibratory approaches for amplified piezoelectric inertia motors.

Doctorant : Fabien DUBOIS

Laboratoire INSA : LaMCoS
Ecole doctorale : ED162 : MEGA

SPA are amplified piezoelectric inertia motors. They operate by converting asymmetrical vibrations into µ-displacements by means of friction, through stick-slip. These vibrations and this friction raise issues related to wear and noise. So, the present work investigates both the tribological and vibratory behaviours of these motors. First, a pin-on-pad tribometer,  actuated  by  a  SPA,  was  developed.  It  led  us  to  observe,  in-situ  and  in operation, interfacial solid flows: the 3rd body. These direct observations carried out in conjunction with post-mortem analyses resulted in decrypting the tribological solicitations and in increasing by ten the lifetime of the motors. Second, numerical and experimental considerations have been proposed to better grasp the vibratory behaviour of SPA. The existing lumped model was modified to a more versatile hybrid lumped-FEM model. The experimental tests made it possible to determine the main acoustic contributor and to reduce the noise level by sixteen dBA. Finally, this dual - tribology/vibratory - approach provided a better understanding of the SPA intricacies. In particular, it led to develop innovative  structures  such  as  a  motor  with  three  degrees  of  freedom  and  two  rotary motors.

Informations complémentaires

  • Amphi Claude Chappe (Bâtiment Claude Chappe, TC)