Application of conducting polymers has been growing widely in different fields such as batteries, solar cells, capacitors
and actuators. Mechanical properties of conducting polymers like flexibility, high power to mass ratio and high active
strain make them potentially applicable to robotic and automation industries. Obviously, a dynamic model of the
actuation phenomenon in conducting polymers is needed to study its controllability and also to optimize the mechanical
performance. De Rossi and colleagues suggest treating the mechanical behaviour of conducting polymers separately
from the viscoelastic structural model and electrochemical actuation. But it has been observed that the effects of
electrochemical actuation and diffusion of ions on the viscoelastic coefficients cannot be neglected in some conducting
polymer actuators, as shown in. In this paper, we present the effects of cyclic voltammetry actuation on shear modulus
of polypyrrole in propylene carbonate and EMI.TSFI as measured by an electrochemical Quartz Crystal Microbalance
(eQCM). The QCM consists basically of an AT-cut piezoelectric quartz crystal disc with metallic electrode films
deposited on its faces. One face is exposed to the active medium. A driver circuit applies an AC signal to the electrodes,
causing the crystal to oscillate in a shear mode, at a given resonance frequency. QCM has been routinely used for the
determination of mass changes. Measured resonance frequency shifts are converted into mass changes by the wellknown
Sauerbrey's equation. In this paper, we correlate the admittance output of QCM to the real shear modulus of
polypyrrole. Then the results of the correlation which contains mechanical data are presented during actuation using two
different types of electrolyte.
Different factors cause vibration. These vibrations make the voyages difficult and reduce comfort and convenience in passenger ships. In this paper, the creating factors of vibration have discussed first, then with mathematical modelling it will be attempted to minimize the vibration over the crew's seat. The modelling consists of a system with two degrees of freedom and by using vibration\isolation with passive method of Tuned Mass Damper (TMD) it will be tried to reduce the vibration over personnel. Moreover using active control systems will be compared with passive systems.
Conducting polymer actuators are being investigated for a number of applications. Both linear contracting/expanding and bending type actuators can be constructed that utilise the redox-induced volume changes in the conducting polymer. Improved actuator performance has been demonstrated by modifications to our helix-tube design. The pitch of the helix and bundling the actuators have increased the strain and force generated. Short-term improvements to the strain were also generated using new dopants, but cycle life was poor in this case. Further studies on the mechanism of actuation have continued to focus attention on the influence of the elastic modulus on the actuation strain. Surprising results have been obtained from polythiophene actuators that show an increased strain and increased work-per-cycle with an increasing applied load in isotonic operation. The observations were explained by an increase in modulus during the contraction cycle of the actuation. Preliminary studies show how the change in modulus can be conveniently measured using an in situ mechanical technique.
Conducting polymer actuators with favourable properties such as linearity, high power density and compliance are of increasing demand in micro applications. These materials generate forces over two times larger than produced by mammalian skeletal muscles. They operate to convert electro chemical energy to mechanical stress and strain. On the other hand, the application of conducting polymers is limited by the lack of a full description of the relation between four essential parameters: stress, strain, voltage and current. In this paper, polypyrrole helix tube micro actuator mechanical characteristics are investigated. The electrolyte is propylene carbonate and the dopant is TBA. PF6. The experiments are both in isotonic and isometric conditions and the input parameters are both electrical and mechanical. A dual mode force and length control and potentiostat / galvanostat are utilized for this purpose. Ultimately, the viscoelastic behaviour of the actuator is presented in this paper by a standard stress relaxation test. The effect of electrical stimulus on mechanical parameters is also explored by cyclic voltametry at different scan rates to obtain the best understanding of the actuation mechanism. The results demonstrate that the linear viscoelastic model, which performed well on conducting polymer film actuators, has to be modified to explain the mechanical behaviour of PPy helix tube fibre micro actuators. Secondly, the changes in mechanical properties of PPy need to be considered when modelling electromechanical behaviour.