Unconventional actuator

Adaptronics Smart materials Smart stmcture Unconventional actuator... 

Actuators can be classified as conventional and unconventional actuators. Conventional actuators are commonly used as essential components for mechatronic systems (see Pig. 1 (left)). These are, for instance, electrical motors, pneumatic actuators, hydraulic pistons, or relays. 

Unconventional actuators are rather high integrated. They are not just an integral part of the system, they are a part of the stmcture itself combining sensing, actuation, and mechanical functions (see Pig. 1 (right)). Unconventional actuators are made of transducer materials. Piezoelectric actuators, shape memory alloy... 

Power amplifiers are generally designed for driving electrically resistive loads. In contrast, unconventional actuators are mainly electrically reactive loads. This section is dedicated to the interaction between the actuator load and the power amplifier, and we will also treat the common amplifier circuit topologies, providing the reader with valuable information that will help him to design his own power amplifier or choose a suitable commercial product. 

Piezoelectric and magnetostrictive actuators in particular, as well as actuators with electrically controllable fluids, are coimted among the unconventional actuators. Actuators with shape memory alloys and polymers as well as other, less common actuators sometimes require very simple and sometimes fairly complex amplifiers, which have to be timed to the actuator and the signals that are to be processed. However, we will not go into the details of such special cases. 

There are many possibilities of implementing power stages for unconventional actuators. In the following, we will introduce their fundamental operating principles and some of their combinations. 

Thomas Wiirtz attended the Hochschule ftir Technik und Wirtschaft in Saarbrucken, Germany (Saarland University of Applied Sciences). Since 1993, at the Laboratory of Process Automation (Saarland University), he has been responsible for the area of power electronics for driving unconventional actuators. In addition to developing product lines mainly for driving piezo actu-... 

PLLA films, with a larger shear piezoelectric constant than the oflier polymers in Table I and non-pyroelectricity, are greatly anticipated to be used as sensors and actuators for realizing unconventional HMIs because of their excellent fiexibility and transparency. A PLLA sensor has been combined with a projected capacitive touch panel to realize a deformation-sensitive touch panel (Ando et al. 2012). The touch sensor comprises a PLLA film, and the electrode of tiie touch sensor has a diamond stracture. A polycarbonate (PC) plate is used as tiie surface plate of the touch panel. The electrode consists of three layers, as shown in Fig. 9 (Ando et al. 2013). On layer 1, an RX electrode was... 

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