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The cost and complexity of aircraft power systems limit the number of integrated system evaluations that can be performed in hardware. As a result, evaluations are often performed using emulators to mimic components or subsystems. As an example, aircraft generation systems are often tested using an emulator that consists of a bank of resistors that are switched to represent the power draw of one or more actuators. In this research, consideration is given to modern wide bandwidth emulators (WBEs) that use power electronics and digital controls to obtain wide bandwidth control of power, current, or voltage. Specifically, this paper first looks at how well a WBE can emulate the impedance of a load when coupled to a real-time model. Capturing the impedance of loads and sources is important for accurately assessing the small-signal stability of a system.

EcoCAR 2: Plugging In to the Future (EcoCAR) is North America's premier collegiate automotive engineering competition, challenging students with systems-level advanced powertrain design and integration. The three-year Advanced Vehicle Technology Competition (AVTC) series is organized by Argonne National Laboratory, headline sponsored by the U. S. Department of Energy (DOE) and General Motors (GM), and sponsored by more than 28 industry and government leaders. Fifteen university teams from across North America are challenged to reduce the environmental impact of a 2013 Chevrolet Malibu by redesigning the vehicle powertrain without compromising performance, safety, or consumer acceptability. During the three-year program, EcoCAR teams follow a real-world Vehicle Development Process (VDP) modeled after GM's own VDP. The VDP serves as a roadmap for the engineering process of designing, building and refining advanced technology vehicles.

We developed a wireless, contact free power transfer mechanism that is safer and robust to imperfect alignment on landing at the base station and that avoid trips back to the launch sites for recharging off power lines. A magnetic field is created using inductor coils on both the transmitting and receiving sides. We use small induction coils around the UAV to increase efficiency and decrease interference. By locating several of these small inductive coils around our quad-rotor UAV, faster recharging is accomplished in comparison to the use of just one coil. In addition, more coils permit larger voltages for more efficient power transfers. On the base station, several folding robotic arms will be used to realign the receiver coils over the transmitter coils. After adequate recharging as measured by battery voltages or power consumption at the base station, the UAV sends a signal to the base station to open the dome to fly away.

This paper presents hydraulic topographies using a network of valves to achieve better energy efficiency, reliability, and performance. The Topography with Integrated Energy Recovery (TIER) system allows the valves and actuators to reconfigure so that flow from assistive loads on actuators can be used to move actuators with resistive loads. Many variations are possible, including using multiple valves with either a single pump/motor or with multiple pump/motors. When multiple pump/motors are used, units of different displacements can be chosen such that units are controlled to minimize time operating at low displacement, thus increasing overall system efficiency. Other variations include configurations allowing open loop or closed loop pump/motors to be used, the use of fixed displacement pump/motors, or the ability to store energy in an accumulator. This paper gives a system level overview and summarizes the hydraulic systems using the TIER approach.

The Indiana Space Grant Consortium is one of 52 members of the National Space Grant College and Fellowship Program (“Space Grant”), which was initiated by NASA in 1988. Space Grant is designed to be a source of NASA-related information, awards, and programs to enhance education, outreach, and workforce development for the United States. Based on the land grant model of public university education, Space Grant seeks to spread the vision of NASA to increase science, technology, engineering, and math (STEM) awareness; NASA-related education; workforce development; outreach and research activities. This paper describes the evolution of these activities in Indiana.

Due to the instabilities that may occur in power systems with regulated loads such as those used in military aircraft, ships, and terrestrial vehicles, many analysis techniques and design methodologies have been developed to ensure stable operation for expected operating conditions. However, many of these techniques are difficult to apply to complex systems and do not guarantee large-displacement stability following major disturbances such as faults, regenerative operation, large pulsed loads, and/or the loss of generating capacity. In this paper, a design paradigm is set forth guaranteeing large-displacement stability of a power system containing a significant penetration of regulated (constant-power) loads for any value of load power up to and including the steady-state rating of the source. Initial investigations are performed using an idealized model of a dc-source to determine the minimum requirements that ensure large-displacement stability.

There has always been, from the very first UAV, a need for providing cost-effective methods of deploying unmanned aircraft systems at high altitudes. Missions for UAVs at high altitudes are used to conduct atmospheric research, perform global mapping missions, collect remote sensing data, and establish long range communications networks. The team of Gevers Aircraft, Technology Management Group, and Purdue University have designed an innovative balloon launched UAV for these near space applications. A UAV (Payload Return Vehicle) with a nested morphing wing was designed in order to meet the challenges of high altitude flight, and long range and endurance without the need for descent rate control with rockets or a feathering mode.

The On-line Project Information System (OPIS) is a LAMP-based (Linux, Apache, MySQL, PHP) system being developed at NASA Ames Research Center to improve Agency information transfer and data availability, largely for improvement of system analysis and engineering. The tool will enable users to investigate NASA technology development efforts, connect with experts, and access technology development data. OPIS is currently being developed for NASA's Exploration Life Support (ELS) Project. Within OPIS, NASA ELS Managers assign projects to Principal Investigators (PI), track responsible individuals and institutions, and designate reporting assignments. Each PI populates a “Project Page” with a project overview, team member information, files, citations, and images. PI's may also delegate on-line report viewing and editing privileges to specific team members. Users can browse or search for project and member information.

Most of the gaseous contaminants generated inside ALS (Advanced Life Support) cabins can be degraded to some degree by microbial degradation in a biofilter. The entry of biofiltration techniques into ALS will most likely involve integration with existing physico-chemical methods. However, in this study, cabin air quality treated by only biofiltration was predicted using the one-box and biofiltration models. Based on BVAD (Baseline Values and Assumptions Document) and SMAC (Spacecraft Maximum Allowable Concentrations), ammonia and carbon monoxide will be the critical compounds for biofilter design and control. Experimentation is needed to identify the pertinent microbial parameters and removal efficiency of carbon monoxide and to validate the results of this preliminary investigation.

Resource recovery, including that of urine water extraction, is one of the most crucial aspects of long-term life support in interplanetary space travel. This paper will consequently examine an innovative approach to processing raw, undiluted urine based on low-temperature freezing. This strategy is uniquely different from NASA's current emphasis on either ‘integrated’ (co-treatment of mixed urine, grey, and condensate waters) or ‘high-temperature’ (i.e., VCD [vapor compression distillation] or VPCAR [vapor phase catalytic ammonia removal]) processing strategies, whereby this liquid freeze-thaw (LiFT) procedure would avoid both chemical and microbial cross-contamination concerns while at the same time securing highly desirable reductions in likely ESM levels.

The application of biological treatment to solid waste is very promising to facilitate recycling of water, carbon, and nutrients and to reduce the resupply needs of long-term crewed space missions. Degradation of biodegradable solid wastes generated during such a mission is under investigation as part of the NASA Center of Research and Training (NSCORT) at Purdue University. Processing in the solids thermophilic aerobic reactor (STAR) involves the use of high temperature micro-aerobic slurry conditions to degrade solid wastes, enabling the recycling of water, carbon, and nutrients for further downstream uses. Related research presently underway includes technical development and optimization of STAR operations as well as a complementary evaluation of post-STAR processing for gas-stream purification, water recovery by condensate purification, and residuals utilization for both mushroom growth media and nutritional support for fish growth.

This paper reviews some applications of lattice Boltzmann methods (LBM) to compute multiphase flows. The method is based on the solution of a kinetic equation which describes the evolution of the distribution of the population of particles whose collective behavior reproduces fluid behavior. The distribution is modified by particle streaming and collisions on a lattice. Modeling of physics at a mesoscopic level enables LBM to naturally incorporate physical properties needed to compute complex flows. In multiphase flows, the surface tension and phase segregation are incorporated by considering intermolecular attraction forces. Furthermore, the solution of the kinetic equations representing linear advection and collision, in which non-linearity is lumped locally, makes it parallelizable with relative ease. In this paper, a brief review of the lattice Boltzmann method relevant to engine sprays will be presented.

Solids thermophilic aerobic reactor (STAR) processing of biodegradable solid waste residuals uses high temperature conditions to reduce waste volume, inactivate pathogens, and render products that may enter the recycle system by providing plant substrate, fish food, and mushroom growth medium. The STAR process recovers and enables the reuse of nutrients, water, and carbon. During the time of this study, STAR was operated at a 3% solids loading rate, with an 11-day retention time at a temperature range of 50-55°C. This document presents the following details: a the evolution to date of the STAR reactor b review of reactor operation and analytical methods c a synopsis of the performance results and related discussion, and d a synopsis of future goals relative to this project's associated research roadmap.

Wheat is a candidate crop for the Advanced Life Support (ALS) system, and cereal grains and their products will be included on long-term space missions beyond low earth orbit. While the exact supply scenario has yet to be determined, some type of post-processing of these grains must occur if they are shipped as bulk ingredients or grown on site for use in foods. Understanding the requirements for processing grains in space is essential for incorporating the process into the ALS food system. The ESM metric developed by NASA describes and compares individual system impact on a closed system in terms of a single parameter, mass. The objective of this study was to compare the impact of grain mill type on the ESM of producing yeast and flat breads. Hard red spring wheat berries were ground using a Brabender Quadrumat Jr. or the Kitchen-Aid grain mill attachment (both are proposed post-harvest technologies for the ALS system) to produce white and whole wheat flour, respectively.

Models for the components of a long-duration UAV power system are set forth. The models include the solar array, solar array power converter, fuel cell and electrolyzer system and corresponding power converter, and propulsion load. Based on these models, a power management control is derived, which when coupled with the component models, are used to simulate power system performance during start-up, through a day-night cycle, and through a solar eclipse.

A procedure for simulating the dynamics of agricultural and forestry machines using mechanical system simulation software is presented. A soil/track interface model including rubber-track and steel-track was introduced as well as equations that can be used to model mechanical and hydraulic power trains commonly found in tracked vehicles. Two rubber-tracked vehicles (agricultural tractors) and two steel-tracked machines (forestry vehicles) were simulated to illustrate the technique, and some analysis results are presented. The examples given in this paper are based on the author’s research over the past several years.

Throughout the industry, organizations struggle with the task of implementing effective human factors programs aimed at reducing maintenance errors. Almost universally, many barriers have frustrated these efforts. In 1998 and 1999, the National Transportation Safety Board sponsored two workshops designed at identifying barriers to the implementation of human factors programs and to explore what was working and what was not working among the many industry efforts. This paper explores the findings of these workshops. In addition, it will report findings of Purdue University studies that reveal a rapid deterioration of even the most successful human factors programs. The research findings disclose several “disconnects” within most organizations which rapidly negate the positive effects of successful human factors and error management training and nullify many proactive human factors programs.

An overview of model development for seated occupants is presented. Two approaches have been investigated for modeling the vertical response of a seated dummy: finite element and simplified mass-spring-damper methods. The construction and implementation of these models are described, and the various successes and drawbacks of each modeling approach are discussed. To evaluate the performance of the models, emphasis was also placed on producing accurate, repeatable measurements of the static and dynamic characteristics of a seated dummy.

This paper explores the current status of error management strategies and human factors efforts within regional airlines. It briefly addresses the potential needs of the environment from a perspective of the market’s accident and incident history as well as anecdotal reports received from members of the regional airline community. It also raises questions concerning the applicability of human factors and error management strategies developed in other segments of aviation to the problems faced within regional airline environments.

Detailed computer models of system components for More Electric Aircraft have been developed using the Advanced Control System Language (ACSL) and its graphical front-end, Graphic Modeller. Among the devices modeled are a wound-rotor synchronous generator with parallel bridge-rectifier outputs, a switched-reluctance generator, and various loads including a DC-DC converter, an inverter-driven induction motor, and an electro-hydrostatic actuator. Results from the simulations are presented together with corroborating experimental test results.