Multi-input digital frequency stabilization of monolithic lasers

A digital control application for the frequency stabilization of optical frequency standards is presented. The standard employed is a monolithic neodymium in yttrium aluminum garnet laser locked to an iodine frequency reference. Traditionally, laser frequency is locked to the reference through analogue loops, which may require a lengthy set-up and a manual search for the reference to which to lock the source. Digital control avoids these steps and provides complete and robust instrument automation. The theory and results of a Digital Control Unit (DCU) designed to improve and facilitate stability set-up and performance are presented. The DCU elaborates frequency error signal between laser and reference at 10 kHz so as to co-ordinate a set of three frequency actuators (temperature servo, piezo-electric ceramics, acousto-optic modulator) capable of compensating frequency drifts below 1 part per 10^12 under normal environmental conditions

Análisis de la táctica defensiva en jugadores de vóley playa masculinos durante el Campeonato de Europa Universitario EUSA GAMES 2013

The digital control design of an interferometric balance for fine space thruster calibration is presented. The problem was suggested by new micro-thrusters generation aiming at thrusts with sub-micro-Newton resolution. The solution, the Nanobalance instrument, under development, will be employed for on ground qualifying thrust time profile and noise with sub-micro-Newton accuracy. The digital control has been designed and tested in parallel to instrument construction, through a fine numerical simulator of the instrument itself and of the environment disturbances, developed within a proprietary control design environment, ControLab. Severe simulation tests have shown that requirements are met. Next step will be Digital Control Unit interfacing to Nanobalance instrument and testing