Etude, conception et optimisation d'une plate-forme de mesure de micro et nano force par flottaison magnétique.

摘要

In microrobotics, the micro and nano force measurement is among the necessary information needed to characterize mechanical interactions present at the micrometer scale. Accordingly, we developed a micro and nano force sensor based on a floating-magnetic principle. The sensor sensign part is a macroscopic rectangular platform on which is applied the forces and the torques to be measured. The sustentation of the platform is done thanks to magnetic forces and upthrust buoyancy applied on four floats placed at its corners. The platform is designed to only measure forces in the horizontal plane and the associated vertical torque. The forces measurement range varies between -100 et +100 micronN with a nanoNewton resolution. The platform works in active mode with a control around its equilibrium configuration (established in absence of external efforts). The nature of return forces used for the implementation of the control loop is electromagnetic. The magnetic and electromagnetic models allow determining forces applied on the platform centre of gravity according to the knowledge of its spatial configuration and currents in the control coils. In terms of application, this platform can be used for deformable micro-objects (micromechanisms, cells, etc...) and microsurfaces characterization.