Fully inkjet-printed dielectric elastomer actuators

Dielectric elastomers (DEs) have received significant attention for their good performance among different smart material transducers. This study demonstrates the feasibility of fabricating dielectric elastomer actuators (DEAs) using exclusively inkjet printing technique. The manufactured unimorph bending cantilevers are composed of a polydimethylsiloxane (PDMS) active layer, sandwiched between two compliant electrodes, and printed onto a thin polyimide (PI) substrate. This study addresses the key fabrication challenges associated with inkjet printing such a layered actuator structure. This entails the consistent printing of the Ag electrodes on the smooth PI substrate, a PDMS layer on the Ag electrodes, the Ag electrodes on the smooth PDMS surface, and the respective steps of processing and curing. The fully inkjet-printed DEAs exhibited a maximum tip displacement of 36 µm in quasi-static operation (1 kV_pp) and 12.8 µm in resonant operation (50 Hz, 800 V_pp). This is the first time that inkjet-printing has been employed to print an entire dielectric elastomer actuator, broadening the outlooks to develop innovative devices that base on smart material transducers.