Simulation Techniques in the Design and Test of a Recovery Phase Solution for an Automated VTOL-UAV Shipboard Recovery System

The NATO/PfP Interoperability and RE-Use Study, NIREUS, is a 13 nation project which is applying the High Level Architecture (HLA) methodology to investigate multinational distributed simulation for use in system design and acquisition. The NIREUS test case uses simulation techniques to represent VTOL (Vertical Take-Off and Landing) air vehicles landing on ships, initially focusing on Maritime Unmanned Air Vehicles (MUAVs). The results of this experience-based study will be applied to the realm of Simulation Based Design and Virtual Prototyping, potentially leading to NATO wide standards. In order to assess potential problems at the design stage of a ship or air vehicle any simulation should attempt to take account of the actual physical effects as closely as possible. One of the fundamental issues associated with operating any UAV from small ships in increasingly difficult weather conditions concerns the recovery phase on-board. The NIREUS team has developed an open framework to represent the different physical disciplines associated with the recovery of a UAV. This paper briefly describes the how the physical characteristics of ship and the air vehicle are represented in the simulation and discusses the methodology and representation of the autonomous recovery system for the MUAV. The UAV is instructed to begin the landing phase once a potential ship motion quiescent period, based on the operational limits of the UAV, has been identified. Guiding the UAV onto the deck is then undertaken using calculations of the estimated position of the deck at the point of touchdown. A system of guidance and control is described to aid in the safe recovery of the air vehicle.