Electro-Ribbon Muscles for Biomimetic Wing Flapping

Birds and bats flap their wings using muscles attached directly to the wing. Bumblebees and other insects, however, drive wing movement by two pairs of muscles in the thorax, the contraction of which squeezes the whole body and causes the wings to flap. Here, we present a bumblebee-inspired compliant actuation mechanism for future autonomous and aerial robotics. The mechanism is powered by a novel thin, lightweight, inexpensive, efficient and powerful solenoid electro-ribbon actuator (SERA) that exploits the dielectrophoretic liquid zipping phenomenon. The actuator can be easily fabricated using a combination of flexible conducting and insulating materials. A SERA, made of a circular steel strip and PVC dielectric, was characterised in terms of stroke, load and work. Its behaviour with different stiffnesses was studied and demonstrated in a flapping-wing architecture to quantify wing shaft movement at various frequencies.