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This paper presents using of FlightGear application for flight simulation of a mini-UAV (Unmanned Aerial Vehicle). The first part of the paper is about general information of UAVs and about the fundamentals of airplane flight mechanics. The main section summarizes the information about FlightGear application and describes a way of using the application to simulate a mini-UAV. The process of altitude change by using autopilot has been simulated. In the created simulation, three stage cascade controller was used for an altitude control. Heading was controlled by 2 stage cascade PID (Proportional-Integral-Derivative) controller. An automatic throttle system was applied for a velocity control. The setting of all controllers is included in the description of the simulation. Finally, the results of FlightGear simulation are discussed. [ABSTRACT FROM AUTHOR]

Due to the physical limitations on the speed of individual processors, we are currently experiencing a paradigm shift in computer architecture towards multi-processor, multi-core and multi-subcore systems. In order to take full advantage of these new architectures, some of the basic models, algorithms and data structures in Molecular Dynamics simulations need to be re-thought. In this paper, I present some simple, generic algorithmic considerations that can improve the performance of such simulations on the IBM Cell Broadband Engine Architecture, a multi-subcore processor. The accumulated effects of these improvements are on par with what can be achieved with hand-tuned architecture-specific optimizations in the innermost loops of the simulation. [ABSTRACT FROM AUTHOR]

The Exploration Systems Architecture defines missions that require rendezvous, proximity operations, and docking (RPOD) of two spacecraft both in Low Earth Orbit (LEO) and in Low Lunar Orbit (LLO). Uncrewed spacecraft must perform automated and/or autonomous rendezvous, proximity operations and docking operations (commonly known as Automated Rendezvous and Docking, AR&D). The crewed versions may also perform AR&D, possibly with a different level of automation and/or autonomy, and must also provide the crew with relative navigation information for manual piloting. The capabilities of the Rendezvous, Proximity Operations and Docking (RPOD) sensors are critical to the success of the Constellation Program; this is carried as one of the CEV Project top risks. The Exploration Technology Development Program (ETDP) AR&D Sensor Technology Project seeks to reduce this risk by increasing technology maturation of selected relative navigation sensor technologies through testing and simulation. One of the project activities is a series of “pathfinder” testing and simulation activities to integrate relative navigation sensors with the Johnson Space Center Six-Degree-of-Freedom Test System (SDTS). The SDTS will be the primary testing location for the Orion spacecraft's Low Impact Docking System (LIDS). Project team members have integrated the Orion GN&C simulation with the SDTS computer system so that real-time closed loop testing can be performed with relative navigation sensors and the docking system in the loop during docking and undocking scenarios. Two relative navigation sensors are being used as part of a “pathfinder” activity in preparation for future testing with the actual Orion sensors. This paper describes the test configuration and test results. [ABSTRACT FROM AUTHOR]