PVC gel based artificial muscles: Characterizations and actuation modular constructions

Abstract

Polymer materials based artificial muscles have the properties of being soft, lightweight and flexible which are similar to the nature muscular actuators. In our previous study, we have developed a contraction type artificial muscle based on plasticized poly vinyl chloride (PVC) gel and meshed electrodes. And we have improved the characteristics to make it close to the level of natural muscle. It has many positive characteristics, such as stable actuation in the air, high output, notable response rate and low power consumption. So a wide application is expected. However, for practical applications, it is necessary to consider some specific criteria, such as performance criteria and structural criteria. In this study, we introduced the most updated properties of PVC gel artificial muscles and proposed three types of mechanical actuation modular constructions for making the PVC gel artificial muscle as a robust actuation device for robotics and mechatronics. And we tested a prototype to examine the effectiveness of the proposed modules. Finally, an analytical model for the static characteristics of PVC gel artificial muscles at different applied voltages was derived and showed good agreement with experimental results measured by a prototype of modules.

High-performance polyvinyl chloride gel artificial muscle actuator with graphene oxide and plasticizer

“…3b. With the removal of the electric field, the PVC gels elasticity causes it to be returned to its initial shape 32 . The charge accumulation on the anode causes the gel to exhibit electrostatic adhesion on the anode surface, and creeping deformation occurs.…”

Thermoplastic electroactive gels for 3D-printable artificial muscles

“…In contrast, plasticisers have been used to make PVC soft and flexible since the 1920s [28], and the normal manufacturing method for plasticised PVC requires no solvent: a dispersion of plasticiser and PVC particles is simply cured at 190-200 °C [29]. The pervasiveness of the solventbased method for manufacturing PVC gel actuators may stem from the fact that the anodophilic PVC gel has almost always been manufactured using DBA plasticiser [7, [20][21][22]24,26,[30][31][32], whose flash point is 113 °C [33], whereas rigid PVC melts at about 170-180°C [34]. This has prevented heat-based manufacture and necessitated the use of solvents.…”

An artificial skeletal muscle for use in pediatric rehabilitation robotics

“…Thermally activated actuators usually have large strain and high force generation capability, which surpass human skeletal muscle. 44,45,53 The most studied and commercially available actuators of this kind are Shape memory alloys (SMAs) 62 , which due to their Young's modulus 2×10 10 Pa, are not considered soft based on aforementioned definition. Although usually in the soft range, shape memory polymers (SMPs) have limited force generation capability 47 .…”

“…Electrical stimulation, however, is considered the most promising activation mechanism, because of its speed, availability, advances, and control systems 50 . Thus even thermally driven actuators use electro-thermal activation 44,46 53 . Liquid crystal elastomers, which are capable of producing large strain (up to the order of %100), have limited response time and stress generation capablity 51 The existing CNT aero gels have low force generation capability 51 .…”