3D printing with light: towards additive manufacturing of soft, electroactive structures

Soft electroactive devices such as dielectric elastomer actuators have been the subject of research for several decades. One of the reasons they have not found many industrial applications to date is the challenge of manufacturing such devices cost-effectively. 3D printing is now widely used to cut manufacturing time and cost in many industries, but functional and soft materials for 3D printing are still very limited. Here we present a process that could be used to 3D print functional soft, electroactive devices like dielectric elastomer actuators and sensors. We propose a simple, low-cost 3D printing platform that uses direct ink writing of elastomer composites with low filler loading of carbon-based nanoparticles. These composites allow the deposition of smooth, uniform layers as well as rapid curing of printed materials with UV light. A diode laser is then used to induce a chemical transformation of the elastomer to create conductive patterns for electrodes with arbitrary shapes and high detail. The process is still limited by the low elasticity of the laser induced electrode material but if more suitable materials can be found, this process could dramatically reduce the time, cost and complexity involved in manufacturing dielectric elastomer devices while at the same time greatly increasing the possible geometric and functional complexity of the 3D printed devices.