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At Boeing’s commercial aircraft production in Everett Washington, the organization that supplies parts to the factory floor (known internally as Company 625) is revising their methods. A new process will deliver parts in kits that correspond to the installation plans used by the mechanics. Several alternative methods are under review. The authors used simulation methods to evaluate and compare these alternatives. This study focuses on the category of parts known as standard fasteners (‘standards’). Through direct observation, interviews with experts, as well as time and motion study, the process flow of the kitting operation was mapped A simulation model was created using the simulation software ARENA to examine two scenarios: the current kitting operation in the factory cribs and the proposed centralization of kitting operation in the Company 625.

An automotive propulsion concept is presented which utilizes liquid nitrogen as the working fluid for an open Rankine cycle. Ambient heat exchangers are used to power an engine that is configured to maximize heat transfer during the expansion stroke. If sufficient heat input during the expansion process can be realized then this cryogenic propulsive system would provide greater automotive ranges and lower operating costs than those of electric vehicles currently being considered for mass production. The feasibility of meeting this engineering challenge has been evaluated and several means of achieving quasi-isothermal expansion are discussed.

The repairing of commercial aircraft is a complex task. Service engineers at Boeing's Commercial Aviation Services group specialize in providing crucial repair information and technical support for its many customers. This paper details factors that influence Boeing's response time to service requests and how to improve it. Information pertaining to over 5000 service requests from 2008 and 2009 was collected. From analysis of this data set, important findings were discovered. One major finding is that between 6 and 8 percent of service requests are late because time/date stamps used in reports were created in a different time zone.

This study investigates using driver prediction to anticipate energy usage over a 160-meter look-ahead distance for a series, plug-in, hybrid-electric vehicle to improve conventional thermostatic powertrain control. Driver prediction algorithms utilize a hidden Markov model to predict route and a regression tree to predict speed over the route. Anticipated energy consumption is calculated by integrating force vectors over the look-ahead distance using the predicted incline slope and vehicle speed. Thermostatic powertrain control is improved by supplementing energy produced by the series generator with regenerative braking during events where anticipated energy consumption is negative, typically associated with declines or decelerations.

Regenerative braking is an important factor in improving hybrid electric vehicle efficiency. This paper proposes a new regenerative braking strategy that activates preemptively during a distracted driving scenario, before service brakes are utilized. The strategy uses onboard advanced driver assistance systems, such as forward facing radar, to detect when an object is approaching fast enough to enable regenerative braking in response. The proposed strategy is simulated on a full-vehicle model of a series plug-in hybrid electric vehicle. A driver model is developed to mimic the behavior of a distracted driver through delayed response time to the changing speed of a lead vehicle. Multiple trials are simulated using different combinations of existing regenerative braking strategies along with the proposed strategy. Results show that a preventative regenerative braking control strategy can recuperate significant amounts of energy while also improving vehicle safety.

Whole-body vibration (WBV) is associated with several adverse health and safety outcomes including low-back pain (LBP) and driver fatigue. The objective of this study was to evaluate the efficacy of three commercially-available air-suspension truck seats for reducing truck drivers’ exposures to WBV. Seventeen truck drivers operating over a standardized route were recruited for this study and three commercially-available air suspension seats were evaluated. The predominant, z-axis average weighted vibration (Aw) and Vibration Dose Values (VDV) were calculated and normalized to represent eight hours of truck operation. In addition, the Seat Effective Amplitude Transmissibility (SEAT), the ratio of the seat-measured vibration divided by the floor-measured vibration, was compared across the three seats. One seat had significantly higher on-road WBV exposures whereas there were no differences across seats in off-road WBV exposures.

Previous studies have shown that use of flight-path displays may lead to increased situational awareness during final approach and landing. However, there are a number of research issues which remain to be investigated concerning the optimum design of a perspective flight-path display. The purpose of this paper is to report the results of a study which investigated the relationship between the geometric field of view, number of tunnels in the display, and flight-path complexity on the subject's ability to fly a computer-simulated aircraft during final approach. Implications of the results for the design of perspective flight-path displays are discussed.

Today's competitive food and produce markets require better understanding of the design of packaged, palletized products in order to minimize product damage during shipping, maintain quality, control costs, and address promotional and environmental concerns. To further define important design parameters, the effects of shipment vibration on palletized products were measured. The premise of this study was that the natural frequencies of the palletized product should be different from those of the vehicle in order to decrease resonant behavior that may lead to packaging failure. The study was conducted in two stages. First, the natural frequencies of the product itself were examined, then the natural frequencies of fully loaded truck trailers were investigated. A description of analytical and experimental methods for evaluating packaging design and suggestions for ways to avoid resonant excitation are presented.

This paper addresses a simulation modeling case study of a batching process. The batching process exists in a multi-server, multi-queue aircraft component manufacturing system where all parts and batches are serial numbered for traceability. Every lot of parts requires a unique set of serial numbers and the sequence of batches is required to follow the airplane master production schedule. The study goal was to identify and provide solutions to shorten arrival time differences among parts going to the same batch in a system of more than 100 shared processes. Queue lengths, resource utilization, bottlenecks, and various scenario comparisons were yielded from simulation modeling exercises.

This paper details the development process and model architecture used in the University of Washington's EcoCAR 2 hybrid supervisory controller. The EcoCAR 2 project challenges 15 universities across North America to create a hybrid vehicle that most effectively minimizes emissions and fuel consumption while still maintaining consumer acceptability. The supervisory controller for the University of Washington was designed to distribute torque to the various electric and combustion drive systems on a parallel though the road plug-in hybrid electric vehicle using Simulink and Stateflow. The graphical interface of Simulink offers some distinct advantages over text-based programming languages. However, there are also significant challenges posed by the software, particularly when several controls engineers are working in parallel on a large model with some type of version control.

Measuring the displacements in vehicle seat suspensions and the displacements the seat has to absorb may assist vehicle seat designers in better designing seats to absorb vibrations. Low frequency seat displacement is important in seat design to identify end-stop events and higher frequency shorter displacements are also important since seat components can be optimized to absorb these smaller displacements. Displacements can be directly measured with special instruments, but it would be less complicated if simple, compact accelerometers could be used to measure the seat displacements. This paper compares accelerometer-derived displacement measurements to known displacements derived from sinusoidal physics and field measured random displacements measured with potentiometers. Using known, controlled sinusoidal displacements, three lab-based experiments were conducted to determine how well accelerometers, using double integration, could measure displacements.

Aerodynamic assessment of icing effects on swept wings is an important component of a larger effort to improve three-dimensional icing simulation capabilities. An understanding of ice-shape geometric fidelity and Reynolds and Mach number effects on iced-wing aerodynamics is needed to guide the development and validation of ice-accretion simulation tools. To this end, wind-tunnel testing was carried out for 8.9% and 13.3% scale semispan wing models based upon the Common Research Model airplane configuration. Various levels of geometric fidelity of an artificial ice shape representing a realistic glaze-ice accretion on a swept wing were investigated. The highest fidelity artificial ice shape reproduced all of the three-dimensional features associated with the glaze ice accretion. The lowest fidelity artificial ice shapes were simple, spanwise-varying horn ice geometries intended to represent the maximum ice thickness on the wing upper surface.

Artificial ice shapes of various geometric fidelity were tested on a wing model based on the Common Research Model. Low Reynolds number tests were conducted at Wichita State University’s Walter H. Beech Memorial Wind Tunnel utilizing an 8.9% scale model, and high Reynolds number tests were conducted at ONERA’s F1 wind tunnel utilizing a 13.3% scale model. Several identical geometrically-scaled ice shapes were tested at both facilities, and the results were compared at overlapping Reynolds and Mach numbers. This was to ensure that the results and trends observed at low Reynolds number could be applied and continued to high, near-flight Reynolds number. The data from Wichita State University and ONERA F1 agreed well at matched Reynolds and Mach numbers. The lift and pitching moment curves agreed very well for most configurations.

Understanding the aerodynamic impact of swept-wing ice accretions is a crucial component of the design of modern aircraft. Computer-simulation tools are commonly used to approximate ice shapes, so the necessary level of detail or fidelity of those simulated ice shapes must be understood relative to high-fidelity representations of the ice. Previous tests were performed in the NASA Icing Research Tunnel to acquire high-fidelity ice shapes. From this database, full-span artificial ice shapes were designed and manufactured for both an 8.9%-scale and 13.3%-scale semispan wing model of the CRM65 which has been established as the full-scale baseline for this swept-wing project. These models were tested in the Walter H. Beech wind tunnel at Wichita State University and at the ONERA F1 facility, respectively. The data collected in the Wichita St.