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A Hybrid Projectile (HP) is a round that transforms into a UAV after being launched. Some HP's are fired from a rifled barrel and must be de-spun and wings-level for lifting surfaces to be deployed. Control surfaces and controllers for de-spinning and wings-leveling were required for initial design of an HP 40 mm. Wings, used as lifting surfaces after transformation, need to be very close to level with the ground when deployed. First, the tail surface area needed to de-spin a 40 mm HP was examined analytically and simulated. Next, a controller was developed to maintain a steady de-spin rate and to roll-level the projectile in preparation of wing deployment. The controller was split into two pieces, one to control de-spin, and the other for roll-leveling the projectile. An adaptable transition point for switching controllers was identified analytically and then adjusted by using simulations.

A Hybrid Projectile (HP) is a tube launched munition that transforms into a gliding UAV, and is currently being researched at West Virginia University. In order to properly transform, the moment of transformation needs to be controlled. A simple timer was first envisioned to control transformation point for maximum distance. The distance travelled or range of an HP can directly be modified by varying the launch angle. In addition, an internal timer would need to be reprogrammed for any distance less than maximum range due to the nominal time to deployment varying with launch angle. A method was sought for automatic wing deployment that would not require reprogramming the round. A body angle estimation system was used to estimate the pitch of the HP relative to the Earth to determine when the HP is properly oriented for the designed glide slope angle. It also filters out noise from an inertial measurement unit (IMU).

This paper documents the numerical and experimental investigation of a new type of wing section being developed at West Virginia University that shows good potential for use in wings in low Reynolds number flows. These wing sections have been designed with a minimum number of flat sides, or facets, which are arranged in such a way as to promote flow over the surface similar to traditional smooth airfoil shapes, but without the complexity of the typically highly contoured airfoil form. 2D numerical techniques have been employed to determine appropriate geometric limitations of the wing section facets, and finite span wings comprised of these faceted wing sections have been tested in wind tunnels in wing-only and wing-plus-body configurations to determine their basic aerodynamic performance. The latest results of these efforts, as well as some speculation as to the mechanisms at work are presented.