Experimental In-Flight Rolling MAV Wing Deployment and Aerodynamic Characterization

Abstract

The deployment dynamics of a tape-spring style, folding MAV wing in flight are complicated and an investigation is made using wind tunnel testing. High speed photography is used to characterize the deployment motion of the wing while a force balance records six- axis aerodynamic loading of the model. An in-flight deployment of a folding wing would be advantageous after an autonomous tube launch, however the dynamics are potentially problematic due to buckling. Steady state aerodynamics of prototype tube-launch MAVs are characterized for both rigid body and compliant, rolling wings. Aerodynamic phenomena associated with the significant relative body size are identified. Wing deployments are demonstrated at four different angles-of-attack at single velocity, while an extreme case deployment is shown at a high velocity. Two-piece cylindrical shells are used to retain the wing prior to deployment and are released by hot-wire cutting of retaining lines. Three phenomena leading improper deployment are noted. Aeroelastic flutter is observed and characterized after the wing deployment at certain conditions.