Ultrathin Dielectric Elastomer Fibers For Actuation

Through this Phase II SBIR project, Elysium Robotics will demonstrate a soft robotic actuator that can be mass-produced at low costs with performance similar to human muscle. This actuator can be scaled from millimeter level to 10s of centimeters; is composed  of a bundle of microfibers that produce tension like natural muscles, with clear superior properties versus hydraulic and electrical actuators used today. This project will miniaturize fiber dimension, dramatically reducing the operating voltage and allowing  the control electronics to be  easily miniaturized as well. Through this SBIR Elysium will deliver to DARPA > 10 sample actuators composed of 100 bundled fiber, where each fiber will have an OD 1% at less than 300V.   Conventional actuators for robotics are electric motors and hydraulic drives. Both are complex, heavy, inefficient, unsafe, and expensive. Motors are terribly inefficient when operating at low speeds—which are needed to actuate robots—a problem that worsens with smaller size. Hydraulic actuators have higher torque density, but the mass of the valves, pumps, and accessories limit system-wide torque density. Hydraulic pistons and electric motors date back two centuries and are technological dead-ends.   Dielectric Elastomers (DE) were identified in the early 2000s as the most promising materials to make artificial muscles capable of solving the robotics actuation problem due to their fast response time, high energy density, large strains, low-cost, noiseless operation, and long lifetimes. Research has mostly focused on DE actuators that consist of an elastomer film–which acts as an insulator–sandwiched between two compliant electrodes forming a parallel plate capacitor. Actuators based on DE films have been difficult to integrate into robotic systems. Elysium Robotics’ core innovation is a DE microfiber actuator that implements a coaxial capacitor and can overcome the limitations of film-based DE actuators. DE microfibers can easily be integrated into robotic applications because they produce tension just like muscles. By leveraging  textile and cable coating manufacturing technologies, these fibers can be scaled down to a few micrometers and produced at low cost.   For this SBIR project, Elysium intends to continue refining hollow silicone dielectric elastomers microfibers via a proprietary process, to further miniaturize, integrate and demonstrate fiber bundles to meet the Phase II objectives.   Similar to the basic architecture of muscle,  DE fibers can scale from the micro to the macro scale. Elysium’s DE microfiber actuators are ideal for micro-robotic applications and human-scale robotic systems.   Elysium will collaborate with a world-class team to develop core technology and in-house capabilities that will advance the technology to TRL-4 towards providing DOD an unprecedented capability for robotic actuation at all scales.