Free-standing actuators

Brisance tests are upsetting tests according to Kast and He the compression of a copper cylinder is determined by actuating a piston instrument alternatively, a free-standing lead cylinder is compressed by the application of a definite cylindrical load of the explosive being tested -< Upsetting Tests. 

Figure 15.1 Conducting-polymer actuation based upon bending of a bilayer or trIlayer actuator in which S-SO-jim-thick polymer layers are typically grown on a metal-coated Inert support the linear stretching of a free-standing film, of several mm to cm in length and the out-of-plane actuation of conducting-polymer films...

S. Hara, T. Zama, W. Takashima, and K. Kaneto, Free-standing gel-hke pol3fpyrrole actuators doped with his(perfluoroalkylsulfonyl)imide exhibiting extremely large strain. Smart Mater. Struct., 14 (6), 1501-1510 (2005). 

R. Kiefer, G.A. Bowmaker, R.P. Cooney, P.A. Kilmartin, and J. Travas-Sejdic, Cation driven actuation for free standing PEDOT films prepared from propylene carbonate electrolytes containing TBACF3SO3, Electrochim. Acta, 53 (5), 2593-2599 (2008). 

A humidity-sensitive conducting polymer actuator made up of PEDOT doped with poly(4-styrenesulfonate) (PEDOT/PSS) was fabricated [47]. Water vapor sorption and electro-active actuating behavior of free-standing PEDOT/PSS films were investigated by sorption isotherm and electromechanical analyses. The non-porous PEDOT/PSS film, with a specific surface area of 0.13 m g sorbed water vapor of 1,080 cm (STP)g , corresponding to 87 wt%, at relative water... 

Hara, S., Zama, T, Takashima, W., Kaneto, K., 2005. Free-standing polypyrrole actuators with response rate of 10.8% s(-l). Synth. Met. 149,199-201. 

Kalinowski T, Rittersma ZM, Benecke W, Binder J (2000) An advanced micromachined fermentation monitoring device. Sens Actuators B 68 281-285 Kronast W, Muller B, Siedel W et al (2001) Single-chip condenser microphone using porous silicon as sacrificial layer for the air gap. Sens Actuators A 87(3) 188-193 Lammel G, Renaud P (2000) Free-standing, mobile 3D porous silicon microstructures. Sens Actuators A 85(l-3) 356-360... 

ChiareUi, P. Della Santa, A. De Rossi, D. Mazzoldi, A. Actuation properties of electrochemical driven polypyrrole free-standing films. J. Int. Mat. Syst. Struc, 6 (1) (1995), pp. 32-37... 

Since the first bending-type actuators from ICPs were demonstrated in the early 1990s, there have been considerable advances in actuator performance, applications and in the understanding of actuation mechanisms. In terms of performance improvements, most attention has been given to free-standing films. Around the turn of the century, the best ICP actuation performances (reported by several different groups) were around 5 % maximum strain, 1 %/s maximum strain rate and 5 MPa maximum sustained stress (isotonic). Since 2000, significant improvements have been reported in each of these areas ... 

A free-standing conducting polymer film or fiber is the simplest actuator (DellaSanta et al. 1997). Eleetroehemieal reactions (6, 7, and 8) promote volume variations following equations (1, 2, 3, 4, and 5), and this can be used to build linear actuators. 

Hara S, Zama T, Takashima W, Kaneto K (2005b) Free-standing gel-like polypyrrole actuators doped with bis(peifluoroalkylsulfonyl)imide exhibiting extremely large strain. Smart Mater Struet 14 1501-1510. 

Fig. 8 Common metrics employed in the study of linear actuators. Illustration depicts isotonic loading of the free-standing PPy film...

Information regarding the appropriate operating load, extent of creep, and cycle life has been obtained by Madden et al. These authors performed a series of experiments on free-standing polypyrrole (PPy(PFg)) film actuators using isotonic testing apparatus (ITA) to investigate creep, passive, and active cycle life (Madden et al. 2007). 

Chiarelli P, Della Santa A, De Rossi D, Mazzoldi A (1995) Actuation properties of electrochera-ically driven polypyrrole free-standing films. J InteU Mater Syst Struct 6 32-37 Cordova FG, Ismail YA, Martinez JG, A1 Harrasi AS, Otero TF (2013) Conducting polymers are simultaneous sensing actuators. In Proceedings of SPIE - The International Society for Optical Engineering, vol 8687... 

The specific geometry is also important. Geometry can either desirably or undesirably constrain motion. For example, a stacked actuator that is short in the direction of motion and attached to rigid end plates that constrain deformation will have a smaller stroke in response to an applied voltage than an actuator with a greater aspect ratio (thinner in the direction transverse to the motion), even if the overall length is the same. In contrast, free-standing film actuators (as well as tubes,... 

---