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Technical Paper

The Importance of HEV Fuel Economy and Two Research Gaps Preventing Real World Implementation of Optimal Energy Management

2017-01-10
2017-26-0106
Optimal energy management of hybrid electric vehicles has previously been shown to increase fuel economy (FE) by approximately 20% thus reducing dependence on foreign oil, reducing greenhouse gas (GHG) emissions, and reducing Carbon Monoxide (CO) and Mono Nitrogen Oxide (NOx) emissions. This demonstrated FE increase is a critical technology to be implemented in the real world as Hybrid Electric Vehicles (HEVs) rise in production and consumer popularity. This review identifies two research gaps preventing optimal energy management of hybrid electric vehicles from being implemented in the real world: sensor and signal technology and prediction scope and error impacts. Sensor and signal technology is required for the vehicle to understand and respond to its environment; information such as chosen route, speed limit, stop light locations, traffic, and weather needs to be communicated to the vehicle.
Journal Article

Electrical Energy Storage to Meet Evolving Aircraft Needs

2012-10-22
2012-01-2199
The value of “ultracapacitors” (also referred to as “supercapacitors” or “electric double layer capacitors” in some literature) as an augmentation device when placed in parallel with “electrochemical” energy storage (i.e. battery) is presented in this paper. Since ultracapacitors possess unique attributes due to their higher value of energy storage density (or Joules/WattHrs per mass) compared to conventional capacitors while maintaining the peak power providing capability (to some degree) typical of conventional capacitors they may provide a near term solution in applications demanding longer battery operating life when placed in parallel. Such demands may be pronounced by the onset of More-Electric-Aircraft peak loads and “cold-crank” Auxiliary Power Unit (APU) electric-starting in demanding cold temperature environments.
Technical Paper

Verification and Validation of Complex Systems

2011-10-18
2011-01-2530
This paper explores the problem of complex safety/security critical software Validation and Verification (V&V). Current methods of V&V, which certify that the software is fit for use, require a significant amount of touch labor - future complex software developments such as NextGen Air Traffic Control will face cost hurdles so high that it may not be deployable. We will take the current V&V technology beyond formal methods (the current state of the art), reducing the V&V problem to an NP-Hard optimization problem solvable by emerging Adiabatic Quantum Computing (AQC) hardware and processing methods. The Quantum V&V (QVV) approach can go beyond software V&V, and can span the entire complex system.
Journal Article

1-g Suit Port Concept Evaluator 2008 Test Results

2009-07-12
2009-01-2572
The Lunar Electric Rover (LER), which was formerly called the Small Pressurized Rover (SPR), is currently being carried as an integral part of the lunar surface architectures that are under consideration in the Constellation Program. One element of the LER is the suit port, which is the means by which crew members perform Extravehicular Activities (EVAs). Two suit port deliverables were produced in fiscal year 2008: a 1-g suit port concept evaluator for functional integrated testing with the LER 1-g concept vehicle and a functional and pressurizable Engineering Unit (EU). This paper focuses on the 1-g suit port concept evaluator test results from the Desert Research and Technology Studies (D-RATS) October 2008 testing at Black Point Lava Flow (BPLF), Arizona. The 1-g suit port concept evaluator was integrated with the 1-g LER cabin and chassis concepts.
Technical Paper

Online Project Information System (OPIS) Description, Annual Reporting Outcomes, and Resulting Improvements

2009-07-12
2009-01-2513
The On-line Project Information System (OPIS) is the Exploration Life Support (ELS) mechanism for task data sharing and annual reporting. Fiscal year 2008 (FY08) was the first year in which ELS Principal Investigators (PI's) were required to complete an OPIS annual report. The reporting process consists of downloading a template that is customized to the task deliverable type(s), completing the report, and uploading the document to OPIS for review and approval. In addition to providing a general status and overview of OPIS features, this paper describes the user critiques and resulting system modifications of the first year of OPIS reporting efforts. Specifically, this paper discusses process communication and logistics issues, user interface ambiguity, report completion challenges, and the resultant or pending system improvements designed to circumvent such issues for the fiscal year 2009 reporting effort.
Technical Paper

The Orion Air Monitor Performance Model; Dynamic Simulations and Accuracy Assessments in the CEV Atmospheric Revitalization Unit Application

2009-07-12
2009-01-2521
The Orion Air Monitor (OAM), a derivative of the International Space Station's Major Constituent Analyzer (MCA) (1–3) and the Skylab Mass Spectrometer (4, 5), is a mass spectrometer-based system designed to monitor nitrogen, oxygen, carbon dioxide, and water vapor. In the Crew Exploration Vehicle, the instrument will serve two primary functions: 1) provide Environmental Control and Life Support System (ECLSS) data to control nitrogen and oxygen pressure, and 2) provide feedback the ECLSS water vapor and CO2 removal system for swing-bed control. The control bands for these ECLSS systems affect consumables use, and therefore launch mass, putting a premium on a highly accurate, fast-response, analyzer subsystem. This paper describes a dynamic analytical model for the OAM, relating the findings of that model to design features required for accuracies and response times important to the CEV application.
Technical Paper

Smoke Detection for the Orion Crew Exploration Vehicle

2009-07-12
2009-01-2542
The Orion Crew Exploration Vehicle (CEV) requires a smoke detector for the detection of particulate smoke products as part of the Fire Detection and Suppression (FDS) system. The smoke detector described in this paper is an adaptation of a mature commercial aircraft design for manned spaceflight. Changes made to the original design include upgrading the materials and electronics to space-qualified components, and modifying the mechanical design to withstand launch and landing loads. The results of laboratory characterization of the response of the new design to test particles are presented.
Technical Paper

Dynamic Thermal Management System Modeling of a More Electric Aircraft

2008-11-11
2008-01-2886
Advancements in electrical, mechanical, and structural design onboard modern more electric aircraft have added significant stress to the thermal management systems (TMS). A thermal management system level analysis tool has been created in MATLAB/Simulink to facilitate rapid system analysis and optimization to meet the growing demands of modern aircraft. It is anticipated that the tracking of thermal energy through numerical integration will lead to more accurate predictions of worst case TMS sizing conditions. In addition, the non-proprietary nature of the tool affords users the ability to modify component models and integrate advanced conceptual designs that can be evaluated over multiple missions to determine the impact at a system level.
Journal Article

High Temperature Sodium Bismuth Titanate Capacitors – A New Product Realized

2008-11-11
2008-01-2863
This paper describes the development of a lead free, high temperature ceramic capacitor material having the base composition of (Na0.5 Bi0.5) TiO3. The goal is to modify this structure to create a material that has the relative permittivity of barium titanate with extended X7R-like properties to 250°C - an X14R. After an extensive compositional and theoretical modeling investigation a composition was selected and capacitors developed. The dielectric has a 1-kHz relative permittivity of ∼1200 with <±15% variation from -25 to +250°C and <5% loss from -55 to +250°C. These capacitors also have very low voltage coefficients, indeed they are positive at the low end of the temperature range, resulting in a combined TC-Vc capacitance variation 0%/-25% of nominal from -55 to +200°C with applied voltage stress from 20 to 260 V/mil.
Technical Paper

Evaluation of Commercial Off-the-Shelf Ammonia Sorbents and Carbon Monoxide Oxidation Catalysts

2008-06-29
2008-01-2097
Designers of future space vehicles envision simplifying the Atmosphere Revitalization (AR) system by combining the functions of trace contaminant (TC) control and carbon dioxide removal into one swing-bed system. Flow rates and bed sizes of the TC and CO2 systems have historically been very different. There is uncertainty about the ability of trace contaminant sorbents to adsorb adequately in a high-flow or short bed length configurations, and to desorb adequately during short vacuum exposures. This paper describes preliminary results of a comparative experimental investigation into adsorbents for trace contaminant control. Ammonia sorbents and low temperature catalysts for CO oxidation are the foci. The data will be useful to designers of AR systems for Constellation. Plans for extended and repeated vacuum exposure of ammonia sorbents are also presented.
Technical Paper

Project Orion, Environmental Control and Life Support System Integrated Studies

2008-06-29
2008-01-2086
Orion is the next vehicle for human space travel. Humans will be sustained in space by the Orion subystem, environmental control and life support (ECLS). The ECLS concept at the subsystem level is outlined by function and technology. In the past two years, the interface definition with other subsystems has increased through different integrated studies. The paper presents the key requirements and discusses three recent studies (e.g., unpressurized cargo) along with the respective impacts on the ECLS design moving forward.
Journal Article

The Orion Air Monitor; an Optimized Analyzer for Environmental Control and Life Support

2008-06-29
2008-01-2046
This paper describes the requirements for and design implementation of an air monitor for the Orion Crew Exploration Vehicle (CEV). The air monitor is specified to monitor oxygen, nitrogen, water vapor, and carbon dioxide, and participates with the Environmental Control Life Support System (ECLSS) pressure control system and Atmosphere Revitalization System (ARS) to help maintain a breathable and safe environment. The sensing requirements are similar to those delivered by the International Space Station (ISS) air monitor, the Major Constituent Analyzer or MCA (1, 2 and 3), and the predecessors to that instrument, the Skylab Mass Spectrometer (4, 5), although with a shift in emphasis from extended operations to minimized weight. The Orion emphasis on weight and power, and relatively simpler requirements on operating life, allow optimization of the instrument toward the mass of a sensor assembly.
Technical Paper

Guidance for Trade Studies of Flight-Equivalent Hardware

2007-07-09
2007-01-3223
Spacecraft hardware trade studies compare options primarily on mass while considering impacts to cost, risk, and schedule. Historically, other factors have been considered in these studies, such as reliability, technology readiness level (TRL), volume and crew time. In most cases, past trades compared two or more technologies across functional and TRL boundaries, which is an uneven comparison of the technologies. For example, low TRL technologies with low mass were traded directly against flight-proven hardware without consideration for requirements and the derived architecture. To provide for even comparisons of spacecraft hardware, trades need to consider functionality, mission constraints, integer vs. real number of flight hardware units, and mass growth allowances by TRL.
Technical Paper

Mark III Space Suit Mobility: A Reach Evaluation Case Study

2007-06-12
2007-01-2473
A preliminary assessment of the reach envelope and field of vision (FOV) for a subject wearing a Mark III space suit was requested for use in human-machine interface design of the Science Crew Operations and Utility Testbed (SCOUT) vehicle. The reach and view of two suited and unsuited subjects were evaluated while seated in the vehicle using 3-dimensional position data collected during a series of reaching motions. Data was interpolated and displayed in orthogonal views and cross-sections. Compared with unsuited conditions, medio-lateral reach was not strongly affected by the Mark III suit, whereas vertical and antero-posterior reach were inhibited by the suit. Lateral FOV was reduced by approximately 40° in the suit. The techniques used in this case study may prove useful in human-machine interface design by providing a new means of developing and displaying reach envelopes.
Technical Paper

Advances in Testing and Analytical Simulation Methodologies to Support Design and Structural Integrity Assessment of Large Monolithic Parts

2006-09-12
2006-01-3179
Significant system efficiency gains can be achieved in high-performance aircraft via a unitized structure that reduces parts count. For instance, reduced parts count leads to substantial engineering logistic cost savings through higher levels of subsystem and mounting hardware integration. It also creates performance benefits by eliminating structural connections. Residual stress management, however, remains a major obstacle to capturing full benefits and broadening the application of unitized structure solutions. This paper describes how Alcoa and others are developing tools to overcome limitations in current testing, evaluation, and design practices attributed to residual stress effects. The authors present recent advancements in fracture toughness and fatigue crack growth characterization, along with a new, integrated approach for improved accounting of residual stress effects during fracture critical component design, manufacturing planning, and life management.
Technical Paper

Trade Study for a Mars Surface Mission Bulk Commodity Supply Scenario: Processed Peanut Oil Versus Bulk Oil

2006-07-17
2006-01-2071
A comparison of resource cost was made between processed peanut oil and a bulk supply of peanut oil within a reference menu using nominal yield values from literature and equivalency factors from the Exploration Life Support (ELS) Baseline Values and Assumptions Document (BVAD). Results of the comparison show a potential mass savings of up to 496.3 kg if a bulk supply of oil were to replace processed peanut oil within identified recipes. Direct comparison of processed peanut oil and bulk oil commodities shows the cost-to-launch value for processed peanut oil will be 3.2 times greater than a bulk supply. This replacement would also remove 164.4 kg of solid waste generated through peanut processing. These values and the general versatility of a bulk supply of oil indicate that recipes under the bulk commodity supply scenario should use a variety of oils.
Technical Paper

Metric Evaluation of Food Packaging Scenarios Intended for a Mars Surface Mission

2006-07-17
2006-01-2067
The National Aeronautics and Space Administration (NASA) is working towards future long duration manned space flights beyond low earth orbit. For these missions several food provisioning strategies are being investigated. Individual, prepackaged meals may be provided throughout the mission or commodities may be taken in bulk and processed while on the planetary surface. To enable these different supply scenarios, a packaging system must be developed that will protect the food or commodity and have minimal impact on system mass. Metric values for a prepackaged scenario and a bulk supply scenario, using current packaging material technologies, were compared. The results of this comparison show that bulk packaging penalties will potentially be more than an order of magnitude less than those of a prepackaged food system.
Technical Paper

Toward Human-Robot Interface Standards: Use of Standardization and Intelligent Subsystems for Advancing Human-Robotic Competency in Space Exploration

2006-07-17
2006-01-2019
NASA's plans to implement the Vision for Space Exploration include extensive human-robot cooperation across an enterprise spanning multiple missions, systems, and decades. To make this practical, strong enterprise-level interface standards (data, power, communication, interaction, autonomy, and physical) will be required early in the systems and technology development cycle. Such standards should affect both the engineer and operator roles that humans adopt in their interactions with robots. For the engineer role, standards will result in reduced development lead-times, lower cost, and greater efficiency in deploying such systems. For the operator role, standards will result in common autonomy and interaction modes that reduce operator training, minimize workload, and apply to many different robotic platforms. Reduced quantities of spare hardware could also be a benefit of standardization.
Technical Paper

Evaluation of a Full-Body Scanning Technique for the Purpose of Extracting Anthropometrical Measurements

2005-07-11
2005-01-3016
A method for capturing full-body scans for the purpose of extracting Extravehicular Activity (EVA) suit measurements is being evaluated. Subjects were marked using reflective spheres enabling researchers to acquire all 118 measurements of the suit sizing protocol. Several researchers measured the subjects using a full-body laser scanner, a motion analysis system, and standard anthropometrical equipment. The linear scanner measurements were compared to the motion analysis data, while the circumferential scanner measurements were compared to the manual data. The mean percent difference between the scanner measurements and motion analysis linear/manual circumferential measurements was 4.21%. It was concluded that the scanner measurements were accurate enough for preliminary sizing of EVA suits.
Technical Paper

New Behavioral Paradigms for Virtual Human Models

2005-06-14
2005-01-2689
The earliest Digital Human Modeling systems were non-interactive analysis packages with crude graphics. Next generation systems added interactivity and articulated kinematic human models. The newest systems use real-time computer graphics, deformable figures, motion controllers, and user interfaces. Our long-term goal is to free the user as much as possible from interactive human model manipulation through direct understanding and execution of task instructions. We present a next generation DHM testbed that includes a scriptable interface, real-time collision-avoidance reach, empirical joint motion models, a versatile locomotion engine, motion capture and synthetic motion blends and combinations, and a smooth skinned scalable human model.
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