Due to their many features including lightweight and low energy consumption, dielectric elastomer (DE) membrane actuators are of interest for a number of industrial applications, such as pumping systems or valve control units. In particular, the use of DEs in valve control units offers advantages over traditional solenoid valves, including lower power requirements and relative simplicity in achieving proportional control. Additionally, DEs generate low thermal dissipation and are capable of virtually silent operation. The contribution of this work is the development of a new valve system based on a circular DE membrane pre-loaded with a linear spring. The valve is designed for pressurized air and operates by actuating a lever mechanism that opens and closes an outlet port. After presenting the operating principle and system design, several experiments are presented to compare actuator force, stroke, and dissipated energy for several pressure differentials and associated volume flows. It is observed that the DE-driven valve achieves a performance similar to a solenoid-based valve, while requiring a significantly lower amount of input energy. In addition, it is shown that DE-membrane valves can be controlled proportionally by simply adjusting the actuator voltage.

Dielectric elastomer (DE) membrane actuators are of great interest for a number of industrial applications, such as valve control units or pumping systems. Their many features include lightweight, silent motion, and low energy consumption. In particular, the high flexibility permits to shape DE actuators with different geometries, allowing to obtain a wide set of actuation modes. This work aims at investigating and characterizing a novel configuration of DE membrane actuator, namely a strip DE membrane capable of out-of-plane motion. At first, manufacturing of pre-stretched strip membranes without electrodes is performed to study the influence of biaxial and uniaxial pre-stretch on the out-of-plane force-displacement characteristics. Subsequently, electrodes are screen-printed on the membranes, and the impact of their size on the force-displacement characteristics is studied. Evaluation of electro-mechanical transduction performance is performed experimentally. Finally, a performance comparison between novel strip actuators and circular actuators developed in the authors' previous works is performed, to highlight the advantages of the novel configuration.

No abstract

No abstract

Dielectric elastomers (DEs) represent a transduction technology with high potential in many application areas, including industry, due to their low weight, flexibility, and low energy consumption. For industrial applications, it is of fundamental importance to quantify the lifetime of DE technology, in terms of both electrical and mechanical fatigue, when operating in realistic environmental conditions. This work contributes toward this direction, by presenting the development of an experimental setup which allows systematic fatigue testing of DE membranes. The setup permits to apply both mechanical and electrical stimuli to several membranes simultaneously, while measuring at the same time their mechanical (force, displacement) and electrical response (capacitance, resistance). The setup allows to test up to 15 DE membranes at the same time. The setup can be placed in a climate chamber, in order to investigate the fatigue mechanisms at different environmental conditions, i.e. in terms of temperature and humidity. After describing the setup, first fatigue results are shown for several DE membranes loaded at different constant voltage values, and mechanically cycled for several hundred thousands of cycles.