R&D 100 winner of the day: Microhydraulic Motors

MIT Lincoln Laboratory’s Microhydraulic Motors are a new way of making things move on a microscale, providing a scalable actuation platform with a torque density that is two orders of magnitude higher than that of electric motors. These actuators have the power to enable precision medical robotics to perform minimally invasive surgeries, shape-changing materials or self-folding displays. Each microhydraulic motors consists of thin layers of solid sheets of polymer separated by fluidic drops, and these layers move relative to each other by internally modifying surface energy using electrowetting. They borrow in form and function from several actuating technologies, including capillary motors, electrowetting conveyors, multi-cycle electrostatic actuators, stepper motors, and biological muscle. Microhydraulic actuators improve on these technologies, however, because in addition to offering high torque and efficiency, microhydraulic actuators increase quadratically in power density when scaled to smaller dimensions and work at a relatively low voltage.