Elimination of periodic nonlinearities of actuators with internal periodic processes

We discuss an algorithm that eliminates the periodic non-linearity of a bimorph piezo actuator by modifying the phase of the voltage waveforms used for driving the actuator. The procedure presented allows for a separate optimization of the motion of the actuator groups in order to obtain the properties desired (such as a specific stepsize or maximum force). The resulting response of a bimorph piezo drive, also under different loads, is experimentally investigated. The optimization process can be applied to other actuators relying on internal periodic processes, if the motion is reproducible, and is limited by measurement noise or manufacturing tolerances only

Drying colloidal systems: laboratory models for a wide range of applications

The drying of complex fluids provides a powerful insight into phenomena that take place on time and length scales not normally accessible. An important feature of complex fluids, colloidal dispersions and polymer solutions is their high sensitivity to weak external actions. Thus, the drying of complex fluids involves a large number of physical and chemical processes. The scope of this review is the capacity to tune such systems to reproduce and explore specific properties in a physics laboratory. A wide variety of systems are presented, ranging from functional coatings, food science, cosmetology, medical diagnostics and forensics to geophysics and art

Sur le passage de l\u27alcool ing\ue9r\ue9 de la m\ue8re au fœtus, en particulier chez la femme

Volume: 5Start Page: 426End Page: 42