Control of Complex Experimental Devices

Research activities:

Adaptive optics (AO) is used in astronomy to obtain high resolution images, close to diffraction limited, of stars and galaxies with ground telescopes, otherwise blurred by atmospheric turbulence.
In order to succesfully compensate for the distorsion induced by athmospheric turbulence one (or more) deformable mirros are deformed; the control action used measurements of the wavefront distorsion.
Next generation AO systems have thousand of sensors and actuators and as such pose non-trivial issues both for modeling and control.
In this respect, it is important to predict the turbulent phase affecting the reconstruction and to this aim the modeling of turbulence starting from the theoretical statistics and a collection of measurements represents a challenging and hot topic in the field.

Homepage: http://automatica.dei.unipd.it/adaptive-optics.html

People: Alessandro Beghi (contact person), Angelo Cenedese, Alessandro Chiuso

Tokamaks are among the most promising devices for obtaining nuclear fusion energy from a high-temperature, ionized gas (plasma).
In tokamaks, there are two components of the confining magnetic field. A set of toroidal field coils, evenly spaced around the torus provides a strong toroidal magnetic field that is kept constant during the whole discharge and provides for plasma stability. The second component, the poloidal field, is responsible for the equilibrium of the plasma. It is produced by the plasma current and can be shaped by using the set of Poloidal Field Coils. The current is induced in the plasma by transformer action, where the primary is constituted by the full set of Central Solenoid and Poloidal Field Coils and the secondary is the plasma ring.
Ongoing specific research topics regard:

  • Plasma dynamic modeling and model order reduction
  • Design of algorithms for real time plasma boundary reconstruction
  • Optimal sensor selection

Homepage: http://automatica.dei.unipd.it/people/cenedese/research/fpmc.html

People: Angelo Cenedese (contact person), Alessandro Beghi

Large frame optical gyroscopes based on He-Ne ring laser (or gyrolaser) technology are presently the most sensitive devices for measuring inertial rotational motion. The use of such systems has been considered in the past for different fundamental Physics applications including experimental tests of fundamental symmetries, axions detection, test of metric theories of gravitation, and gravitational waves detectors.  Moreover, ring lasers have been recently proposed as the core element of an innovative portable six-component sensor for designed seismological field studies: e.g. tomographic inversion, monitoring Earth’s free oscillations, passive seismic imaging, cutting edge seismic tomography, volcanic processes study, ocean-bottom seismic recordings, and others earthquake related studies. The research activity focuses on studying new metrology and control approaches to obtain measurements and to control with the required accuracy the ring lengths for fundamental Physics applications.
Ongoing specific research topics regard:

  • the design and testing of an innovative metrology setting
  • the study and design of an advanced, multivariable, non-linear algorithm for mirror control, based on differential geometry and manifold  theory 

Homepage: http://automatica.dei.unipd.it/people/beghi/research.html

People: Alessandro Beghi (contact person)