Dynamic modeling, control aspects and model predictive control of a parafoil and payload system

Control issues are investigated for a parafoil and payload system with left and right parafoil brakes used as the control mechanism. It is shown through dynamic modeling and simulation that parafoil and payload systems can exhibit two basic modes of lateral control, namely, roll and skid steering. Using a small parafoil and payload aircraft, glide rates and turn performance were measured and compared against a 9 DOF simulation model. This work shows that to properly capture control response of parafoil and payload aircraft, tilt of the parafoil canopy must be accounted for along with left and right parafoil brake deflection. Alternative methods of controlling a parafoil and payload by tilting the canopy for lateral control and changing rigging angle for longitudinal control are evaluated. A model predictive control strategy is developed for an autonomous parafoil and payload system. It is demonstrated in flight tests that a model predictive control strategy is a natural and effective method of achieving trajectory tracking in a parafoil and payload system

Shipboard Landing Challenges for Autonomous Parafoils

21st AIAA Aerodynamic Decelerator Systems Technology Conference, Dublin, Ireland, May 23-26, 2011.This paper examines some of the challenges that must be overcome if future aerial delivery systems are to have the capability to land on the _ight deck of a ship underway. The unique aspects of trajectory planning for landing on a shipﾒs _ight deck are _rst examined, followed by formulation of the position estimation problem for a moving target. Some preliminary investigations into characterizing the wind over a moving landing platform at sea are then described. Finally, experimental results are presented for testing of a small prototype autonomous parafoil with a simple moving target on land

Mobile system for precise aero delivery with global reach network capability

This paper discusses the current status of the development of the mobile aerial delivery system to be further employed in a variety of different applications. High accuracy of the developed system enables its use in precision troop resupply, precise sensors placement, urban warfare reconnaissance and other similar operations. This paper overviews the overall system architecture and components of the developed aero delivery system itself and then proceeds with describing the current status of integrating it with an advanced deployment platform, unmanned aerial system, to achieve mobility and autonomy of operations. The paper also discusses some other systems in development pursuing similar goals and reviews some novel applications that become possible with the developed aerial delivery system

Optimization of the ADS Final Turn Maneuver in 2D and 3D

21st AIAA Aerodynamic Decelerator Systems Technology Conference, Dublin, Ireland, May 23-26, 2011.This paper deals with the problem of optimization of the final turnﾖinto-the-wind maneuver of an aerial delivery system with account of the best known winds. The wind model required for the optimization algorithm to work may utilize onboard wind estimates only, incorporate the ground winds provided a priori or on-line by the target ground station, or be based on the winds measured and uplinked by the preceding system. The previous work by the authors took care of the major touchdown error contributor, downwind variation of the winds. The effect of these variations was mitigated by constantly recomputing an optimal reference trajectory to complete a final turn in a given time. This paper presents some modifications of the original optimization routine to accommodate some specific applications including intentional landing with a substantial crosswind component and operating in the mountainous areas with significant variations in the vertical component of the wind (updrafts and downdrafts). Specifically, the paper presents derivation of equations to account for one-, two- and three-dimensional structure of the wind. In addition, adjustments to the optimal control problem using the direct-method-based approach developed earlier for a simple one-dimensional wind model are developed

State-of-the-art in control of aerial payload delivery

This paper introduces a miniature prototype of an aerial payload delivery system developed by the authors and discusses its performance as compared to other commercially available systems. Its superb performance is assured by using advanced guidance and control algorithms resulting in establishing and tracking an inertial reference trajectory, which is constantly updated based on the best estimates of the ground winds. The paper also discusses the novel networking capability of the developed system and briefly talks about its further upgrades