Foldable compliant actuators for RC aircraft

The foldable DEA actuator


Foldable robots require foldable actuators. Folding allows robots to be stored in very compact configurations, to be deployed, and to change shape. Since DEA are intrinsically soft and can be made stretchable, they enable new ways of making folding robots.
We have developed a DEA-based compliant bidirectional actuator, based on antagonistic elastomer actuators and a support structure using elastic hinges that allows passive folding. The prototype was designed as the elevon in a small drone, and is shown below in unfolded and fully folded states.

Actuator mechanism


Elevon actuator



Micro Air Vehicle demo

We developed a remotely controlled fixed wing micro air vehicle (MAV) as an application to demonstrate the feasibility of the foldable actuator to a challenging problem. The aircraft shown below has a wing span of 40 cm and a mass of 137 grams and uses two foldable actuators as elevons for pitch and roll control. We have flown the MAV numerous times and found the DEA actuators allow for excellent controllability of the aircraft, as well as being very resistant to harsh handling.

Details of the actuator design and aircraft performance can be found in our publication in IEEE Transactions on Mechatronics.