In Field Application of an Innovative Sensor for Monitoring Road and Runway Surfaces

Water and ice detection over road and runway surfaces is important to improve traffic safety and to reduce maintenance costs. An innovative low cost capacitive sensor was endowed with an algorithm based on the time derivative of the measured capacitance to indicate the transitions between dry, wet, or icy state of road and runway surfaces. The sensor was investigated theoretically and validated with experiments on field

RF circulator structures via offset lithography

Further developments are reported of the conductive lithographic film (CLF) process in which components of radio-frequency circulators are fabricated economically via offset lithography. The performance of centre conductor elements printed from silver-loaded inks on polymer substrates is compared with that of conventional solid copper structures

Comb-drive actuators for large displacements

The design, fabrication and experimental results of lateral-comb-drive actuators for large displacements at low driving voltages is presented. A comparison of several suspension designs is given, and the lateral large deflection behaviour of clamped - clamped beams and a folded flexure design is modelled. An expression for the axial spring constant of folded flexure designs including bending effects from lateral displacements, which reduce the axial stiffness, is also derived. The maximum deflection that can be obtained by comb-drive actuators is bounded by electromechanical side instability. Expressions for the side-instability voltage and the resulting displacement at side instability are given. The electromechanical behaviour around the resonance frequency is described by an equivalent electric circuit. Devices are fabricated by polysilicon surface micromachining techniques using a one-mask fabrication process. Static and dynamic properties are determined experimentally and are compared with theory. Static properties are determined by displacement-to-voltage, capacitance-to-voltage and pull-in voltage measurements. Using a one-port approach, dynamic properties are extracted from measured admittance plots. Typical actuator characteristics are deflections of about at driving voltages around 20 V, a resonance frequency around 1.6 kHz and a quality factor of approximately 3

Biomimetic microelectronics for regenerative neuronal cuff implants

Smart biomimetics, a unique class of devices combining the mechanical adaptivity of soft actuators with the imperceptibility of microelectronics, is introduced. Due to their inherent ability to self‐assemble, biomimetic microelectronics can firmly yet gently attach to an inorganic or biological tissue enabling enclosure of, for example, nervous fibers, or guide the growth of neuronal cells during regeneration