The Experts below are selected from a list of 330 Experts worldwide ranked by ideXlab platform

Clement D. Diloreto - One of the best experts on this subject based on the ideXlab platform.

  • Advanced Space Transportation System Ground Operations Study
    2014
    Co-Authors: Clement D. Diloreto
    Abstract:

    This paper presents partial results of a ground operations study for a series of Shuttle Derived Vehicles (SDV's). The paper covers hardware and operational impacts for Kennedy Space Center (KSC) and Vandenberg Air Force Base (VAFB) resulting from processing any one of three different SDV configurations while maintaining Space Transportation System (STS) operations. The SDV configurations were assembled from Shuttle-type hardware (e.g., Solid Rocket Boosters (SRB's), External Tanks (ET's), Space Shuttle Main Engines (SSME's) and Orbiter subsystems). One configuration incorporates a side mounted payload carrier/ propulsion module similar to the Orbiter on STS. A second configuration incorporates an inline payload carrier and propulsion module. The third configuration is the STS vehicle with an additional payload shroud structure located aft of the ET with approximately the same volume as the Orbiter Payload Bay. For each launch vehicle (LV) configuration and associated payloads, the paper presents the launch site impacts including new and modified facilities. Operational impacts were defined that included assessments of schedules, mixed (STS/SDV) fleet analysis, test procedures, and software.

J T Lyons - One of the best experts on this subject based on the ideXlab platform.

  • minimum hamiltonian ascent trajectory evaluation mastre program update to automatic flight trajectory design performance prediction and vehicle sizing for support of Shuttle and Shuttle Derived Vehicles users manual
    1993
    Co-Authors: J T Lyons
    Abstract:

    The Minimum Hamiltonian Ascent Trajectory Evaluation (MASTRE) program and its predecessors, the ROBOT and the RAGMOP programs, have had a long history of supporting MSFC in the simulation of space boosters for the purpose of performance evaluation. The ROBOT program was used in the simulation of the Saturn 1B and Saturn 5 Vehicles in the 1960's and provided the first utilization of the minimum Hamiltonian (or min-H) methodology and the steepest ascent technique to solve the optimum trajectory problem. The advent of the Space Shuttle in the 1970's and its complex airplane design required a redesign of the trajectory simulation code since aerodynamic flight and controllability were required for proper simulation. The RAGMOP program was the first attempt to incorporate the complex equations of the Space Shuttle into an optimization tool by using an optimization method based on steepest ascent techniques (but without the min-H methodology). Development of the complex partial derivatives associated with the Space Shuttle configuration and using techniques from the RAGMOP program, the ROBOT program was redesigned to incorporate these additional complexities. This redesign created the MASTRE program, which was referred to as the Minimum Hamiltonian Ascent Shuttle TRajectory Evaluation program at that time. Unique to this program were first-stage (or booster) nonlinear aerodynamics, upper-stage linear aerodynamics, engine control via moment balance, liquid and solid thrust forces, variable liquid throttling to maintain constant acceleration limits, and a total upgrade of the equations used in the forward and backward integration segments of the program. This modification of the MASTRE code has been used to simulate the new space Vehicles associated with the National Launch Systems (NLS). Although not as complicated as the Space Shuttle, the simulation and analysis of the NLS Vehicles required additional modifications to the MASTRE program in the areas of providing additional flexibility in the use of the program, allowing additional optimization options, and providing special options for the NLS configuration.

Heileman, Gregory L. - One of the best experts on this subject based on the ideXlab platform.

  • Paper Session II-B - Simulating Shuttle and Derivative Vehicle Processing at Kennedy Space Center
    Scholarly Commons, 1991
    Co-Authors: Khajenoori Soheil, Heileman, Gregory L.
    Abstract:

    Rockwell International Space Systems Division is teamed with the University of Central Florida on a research project to develop an automated simulation system to model ground processing scenarios for the Shuttle and Shuttle-Derived Vehicles. This simulation system is necessary to evaluate launch site facilities requirements and estimate life-cycle costs of future space programs. This paper presents the results of initial simulation modeling of the orbiter processing critical path at Kennedy Space Center (KSC). An approach is presented for the planned capabilities to simulate mixed fleet processing and to perform sensitivity, capacity, cost, and risk analyses. Potential expert system applications for the simulation system are presented, such as a resource allocation tool for standdown periods or a long-range scheduling tool for future programs like the Space Exploration Initiative. The simulation model will be developed using the object-oriented languages MOD SIM II and C+ + . This model is different than other software tools currently used for planning at KSC in that it is stochastic rather than deterministic. A deterministic model assumes all parameters of the model are known constants. A stochastic system defines the operations process using an indexed collection of random variables. The modeling system will be expandable using object-oriented inheritance techniques in which facilities and Vehicles are modeled as templates. This system is different from other planning systems used at KSC in that supplemental vehicle and/or facility data can be introduced during program execution. This technique allows effective modeling of dynamic launch site environments for future programs

Best Joel - One of the best experts on this subject based on the ideXlab platform.

  • Evaluation of a Shuttle Derived Vehicle (SDV) for Cargo Transportation
    2005
    Co-Authors: Olsen, Ronald A., Engler, Leah M., Meacham, Stephen B., Garner Tim, Davis, Stephan R., Roman, Jose M., Threet G. E., Crumbly Christopher, Krupp, Donald R., Best Joel
    Abstract:

    In this new era of space exploration, a host of launch Vehicles are being examined for possible use in transporting cargo and crew to low Earth orbit and beyond. Launch Vehicles Derived from the Space Shuttle Program (SSP), known as Shuttle Derived Vehicles (SDVs), are prime candidates for heavy-lift duty because of their potential to minimize non-recurring costs and because the Shuttle can leverage off proven high-performance flight systems with established ground and flight support. To determine the merits of SDVs, a detailed evaluation was performed. This evaluation included a trade study and risk assessment of options based on performance, safety reliability, cost, operations, and evolution. The purpose of this paper is to explain the approach, processes, and tools used to evaluate launch Vehicles for heavy lift cargo transportation. The process included defining the trade space, characterizing the concepts, analyzing the systems, and scoring the options. The process also included a review by subject experts from NASA and industry to compare past and recent study data and assess the risks. A set of technical performance measures (TPMs) was generated based on the study requirements and constraints. Tools such as INTROS and POST were used to calculate performance, FIRST was used for prediction of reliability, and other software packages, both commercial and NASA-owned, were applied to study the trade space. By following a clear process and using the right tools a thorough assessment was performed. An SDV can be classified as either a side-mount vehicle (SMV) or an in-line vehicle OLV). An SMV is a Space Shuttle where the Orbiter is replaced by a cargo carrier. An ILV is comprised of a modified Shuttle External Tank (ET) with engines mounted to the bottom and cargo mounted atop. For both families of Vehicles, Solid Rocket Boosters (SRBs) are attached to the ET. The first derivate of Shuttle is defined as the vehicle with minimum changes necessary to transform the Space Shuttle into an SDV. Deltas from the first derivate were also formulated to study more SDV options. Examples of deltas include replacing the SRBs with larger and/or more SRBs, adding an upper stage, increasing the size of the ET, changing the engines, and modifying the elements. Challenges for SDV range from tailoring infrastructure to meeting the exploration schedule. Although SDV is based on the Space Shuttle, it still includes development risk for designing and building a Cargo Carrier. There are also performance challenges in that Shuttle is not optimized for cargo-only missions, but it is a robust system built on reusability. Balancing the strengths and weaknesses of the Shuttle to meet Lunar and Mars mission objectives provides the framework for an informative trade study. SDV was carefully analyzed and the results of the study provide invaluable data for use in the new exploration initiative

Khajenoori Soheil - One of the best experts on this subject based on the ideXlab platform.

  • Paper Session II-B - Simulating Shuttle and Derivative Vehicle Processing at Kennedy Space Center
    Scholarly Commons, 1991
    Co-Authors: Khajenoori Soheil, Heileman, Gregory L.
    Abstract:

    Rockwell International Space Systems Division is teamed with the University of Central Florida on a research project to develop an automated simulation system to model ground processing scenarios for the Shuttle and Shuttle-Derived Vehicles. This simulation system is necessary to evaluate launch site facilities requirements and estimate life-cycle costs of future space programs. This paper presents the results of initial simulation modeling of the orbiter processing critical path at Kennedy Space Center (KSC). An approach is presented for the planned capabilities to simulate mixed fleet processing and to perform sensitivity, capacity, cost, and risk analyses. Potential expert system applications for the simulation system are presented, such as a resource allocation tool for standdown periods or a long-range scheduling tool for future programs like the Space Exploration Initiative. The simulation model will be developed using the object-oriented languages MOD SIM II and C+ + . This model is different than other software tools currently used for planning at KSC in that it is stochastic rather than deterministic. A deterministic model assumes all parameters of the model are known constants. A stochastic system defines the operations process using an indexed collection of random variables. The modeling system will be expandable using object-oriented inheritance techniques in which facilities and Vehicles are modeled as templates. This system is different from other planning systems used at KSC in that supplemental vehicle and/or facility data can be introduced during program execution. This technique allows effective modeling of dynamic launch site environments for future programs