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

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

Influence of ionic and non-ionic radiographic contrast media on leukocyte adhesion molecules.

BACKGROUND: Many papers have focused on the importance of granulocytes in the process of reperfusion and ischemia. Most of the clinical studies measured several parameters of this process during and after coronary angiography, without taking into account the effect of the radiographic contrast media (RCM) used during this procedure. MATERIALS AND METHODS: We performed a randomized patient study (n = 37) to evaluate the effect of ionic and non-ionic RCM on granulocyte adhesion during coronary angiography. We also evaluated the influence of the ionicity and osmolarity of the different substances on granulocyte adhesion molecules in in vitro experiments. RESULTS: The osmolarity of patient serum samples increased from 302 +/- 1 to 309 +/- 1 mOsm/kg (p < 0.05) after infusion of RCM. The CD11b expression in the samples of the non-ionic RCM treated group increased from 221 +/- 21 MFI to 377 +/- 30 MFI (p < 0.05) measured as the absolute mean fluorescence intensity (MFI), yet did not alter significantly in the ionic RCM group. In contrast, the in vitro experiments showed a reduction of the CD11b expression from 360 +/- 70 MFI to 149 +/- 30 MFI (p < 0.05) in the ionic RCM group. CONCLUSIONS: The upregulation of adhesion molecules was significantly reduced in vivo with ionic RCM, while ionic substances caused opposite effects in vitro. This effect should be taken into account when performing leukocyte functional analysis of samples taken during angiography

Effects of computer training and Internet usage on the well-being and quality of life of older adults: A randomized, controlled study

The quality of life of older adults may be improved by the use of computer or Web-based services. A limited number of experimental studies on this topic have shown mixed results. We carried out a randomized, controlled intervention study that aimed to examine the causal relationship between computer use and measures of physical well-being, social well-being, emotional well-being, development and activity, and autonomy. We randomly assigned a group of 191 participants to an intervention group, a training–no intervention group, or a no training– no intervention group. A fourth group consisted of 45 participants with no interest in computer use. We collected data at baseline, after 4 months, and after 12 months. The results showed that using computers and the Internet neither positively nor negatively influenced everyday functioning, well-being and mood, and the social network of healthy older individuals. We discuss possibilities for future studies. Key Words: Computer use—Internet—Well-being. INDEPENDENT functioning in Western society is increas-ingly difficult without information technology (IT) skills

An Animal-Assisted Intervention Study in the Nursing Home: Lessons Learned

AAI studies in the nursing home pose a specific set of challenges. In this article the practical and ethical issues encountered during a Dutch psychogeriatric nursing home AAI study are addressed with the aim of sharing our experiences for future researchers as well as AAI practitioners in general. In our study we compared three groups of clients with dementia who participated in group sessions of either visiting dog teams, visiting FurReal Friend robot animals, or visiting students (control group) and monitored the effect on social interaction and neuropsychiatric symptoms through video analysis and questionnaires. We encountered the following four categories of challenges during our study. Participant-related challenges include the legal implications of working with vulnerable patients, the practical implications of a progressive neurodegenerative disease with accompanying memory loss and behavioral problems, and the ethical implications of the use of robot animals for people with diminished cognitive functions. A very important challenge involves the selection of the participating dogs and ensuring animal welfare during the study. We partnered with a local university of applied sciences to help us successfully address these issues. The nursing home setting poses several practical challenges due to its inherent organizational structure, the high workload of nursing home staff, and an often suboptimal environment for a controlled randomized trial, especially when comparing nonpharmacological interventions. Balancing the desire for scientifically sound procedures with the practical limitations of a nursing home setting is often difficult and requires specific considerations

Robust Trajectory Planning for Autonomous Parafoils under Wind Uncertainty

A key challenge facing modern airborne delivery systems, such as parafoils, is the ability to accurately and consistently deliver supplies into di cult, complex terrain. Robustness is a primary concern, given that environmental wind disturbances are often highly uncertain and time-varying, coupled with under-actuated dynamics and potentially narrow drop zones. This paper presents a new on-line trajectory planning algorithm that enables a large, autonomous parafoil to robustly execute collision avoidance and precision landing on mapped terrain, even with signi cant wind uncertainties. This algorithm is designed to handle arbitrary initial altitudes, approach geometries, and terrain surfaces, and is robust to wind disturbances which may be highly dynamic throughout the terminal approach. Explicit, real-time wind modeling and classi cation is used to anticipate future disturbances, while a novel uncertainty-sampling technique ensures that robustness to possible future variation is e ciently maintained. The designed cost-to-go function enables selection of partial paths which intelligently trade o between current and reachable future states. Simulation results demonstrate that the proposed algorithm reduces the worst-case impact of wind disturbances relative to state-of-the-art approaches.Charles Stark Draper Laborator

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