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Technical Paper

“Zero Defects”, Statistically Considered

2000-09-11
2000-01-2605
The requirement of “zero defects” is rapidly finding its way as a “standard” of quality in numerous quarters. This phrase has great psychological appeal, and is often taken literally at all levels in an organization even though quality motivation may be the intention. It is common to believe that when zero defects are found in the sample, this must be the case for “all the rest” as well. In this paper the technical side of “zero defects” is examined. We look at the statistics of zero defects and show what is implied about lot or process quality when zero defects is the actual sample outcome. The focus is on attribute measurements and includes some special cases where a significant measurement error exists and cases where a Bayesian statistical analysis may be appropriate.
Journal Article

“Verify-on-Demand” - A Practical and Scalable Approach for Broadcast Authentication in Vehicle-to-Vehicle Communication

2011-04-12
2011-01-0584
In general for Vehicle-to-Vehicle (V2V) communication, message authentication is performed on every received wireless message by conducting verification for a valid signature, and only messages that have been successfully verified are processed further. In V2V safety communication, there are a large number of vehicles and each vehicle transmits safety messages frequently; therefore the number of received messages per second would be large. Thus authentication of each and every received message, for example based on the IEEE 1609.2 standard, is computationally very expensive and can only be carried out with expensive dedicated cryptographic hardware. An interesting observation is that most of these routine safety messages do not result in driver warnings or control actions since we expect that the safety system would be designed to provide warnings or control actions only when the threat of collision is high.
Technical Paper

“Targeting Consumer Needs in the Perfect Storm: Changing the Automotive Lifestyle”

2008-10-20
2008-21-0038
The intersection of changing lifestyles and evolving transportation needs finds smart USA well positioned for launch in 2008 during one of the most competitive periods in U.S. automotive history. In a zero sum market with new global entrants competing for single points of share, where quality levels have been redefined and fractions of points separate the best from the challengers, lifestyle awareness, innovation and product positioning become the differentiators. Simply adding features has left some with hefty investments and confused consumers. Bigger is not always better. More is not always desirable. The real opportunity for new entrants to the US market may be defined within niche markets where changing lifestyles allow for the emergence of new segments. Today, smart USA has surfaced as a clear example of right product, right place, right time.
Technical Paper

“Taguchi Customer Loss Function” Based Functional Requirements

2018-04-03
2018-01-0586
Understanding customer expectations is critical to satisfying customers. Holding customer clinics is one approach to set winning targets for the engineering functional measures to drive customer satisfaction. In these clinics, customers are asked to operate and interact with vehicle systems or subsystems such as doors, lift gates, shifters, and seat adjusters, and then rate their experience. From this customer evaluation data, engineers can create customer loss or preference functions. These functions let engineers set appropriate targets by balancing risks and benefits. Statistical methods such as cumulative customer loss function are regularly applied for such analyses. In this paper, a new approach based on the Taguchi method is proposed and developed. It is referred to as Taguchi Customer Loss Function (TCLF).
Technical Paper

“Symbiose”: Technology Developments for Bioregeneration in Space

1994-06-01
941348
Dedicated technology has been developed to support long-term biological experiments on-board spacecraft. These developments include a microgravity compatible tubular photo bioreactor for the cultivation of micro algae at very high biomass concentrations and with very high gas exchange rates, a microgravity compatible gas / liquid phase separator which also works as a pneumatic low shear-stress pump, a microgravity compatible dehumidifier, and a maltose separating reverse osmosis unit. Integration of these technologies into a partially closed artificial ecosystem form the foundation of the SYMBIOSE concept (System for Microgravity Bioregenerative Support of Experiments).
Technical Paper

“Standardizing the Datasheet” Towards Auto-Code Generation Efficiency

2009-04-20
2009-01-0270
Software programs in non-application areas such as Board Support Packages, Hardware Abstraction Layers, signal processing and data acquisition are more or less very standard and common across many applications. These form a major part of the “platform” software, which changes very little. However, it is seen that many a time, efforts are spent resolving issues in the hardware dependent layers rather than concentrating on the application at hand, despite the fact that the software controlling the hardware has been developed many times. There are many reasons why this section of the software is rewritten many times over: different coding standards, different software architecture and layering concepts, the dreadful cut-and-paste methods, and so on. Introduction of a tool-based code configurator and generator eliminates access to the code and focuses on configuring a pre-written set of SW procedures. Advantages: Standardization, reuse and high levels of productivity.
Technical Paper

“Space-BEE: Space Biomedical Exercise Environment” A Personal Centrifuge within an Inflatable Structure

2005-07-11
2005-01-3049
This paper presents a conceptual design of a short-radius centrifuge for orbital application, contained in an inflatable structure. The objectives of this design are: to support the physical effectiveness of the crew by offering an exercise facility; to provide a test bed for biomedical experiments on human centrifugation in orbit; and to offer recreational benefits during long periods of confinement. The use of a pneumatic structure that can expand in orbit allows maximizing the radius of the centrifuge within mass and launch constraints. The proposed project is composed of elements with standard interfaces; its environmental design is based on human factor considerations from biomedical literature, and it respects current ergonomics and NASA standards.
Technical Paper

“SHIFT-MATE” A Fuel Efficiency Monitor

1985-12-01
852340
The SHIFT-MATE is a dashboard mounted computer based device that cues a truck driver to shift more efficiently. Through electronic circuitry, key vehicle parameters are monitored, computed, then via graphic display, instructs the driver when to shift for improved fuel economy. The theory of operation is described in the text.
Technical Paper

“Rubber Coupling” at a 4×4 Transmition System

2003-11-18
2003-01-3684
There are many different vibration sources in a car. Engine, gears, road roughness, impacts against the wheels cause vibration and sound that can decrease the parts and the car durability as well as affect drivability, safety and passengers and community comfort. In 4×4 cars, some extra vibration sources are the parts responsible for transmitting the torque and power to the rear wheels. Each of them has their own vibration modes, excited mostly by its imbalance or by the second order engine vibration. The engine vibration is a very well known phenomena and the rear driveshaft is designed not to have any vibration mode in the range of frequencies that the engine works or its second order. The imbalance of a driveshaft is also a design requirement. That means, the acceptable imbalance of the driveshaft is limited to a maximum value.
Technical Paper

“Rigidization-on-Command”™ (ROC) Resin Development for Lightweight Isogrid Booms with MLI

2003-07-07
2003-01-2342
The “Rigidization-on-Command”™ (ROC™) resin development has focused on the development of resin systems that use UV light cure for rigidization. Polymeric sensitizers have been incorporated into the resin formulations to promote cure using Pen-Ray lamps and UV light-emitting diodes (LED's). Formulations containing the polymeric sensitizers were examined by FTIR and DSC. Complete cure was observed after 15 min. exposure with the Pen-Ray lamps. Performance of the Pen-Ray lamps and UV LEDs was thoroughly characterized. Thermal models were developed to optimize the performance of the of the MLI insulation thermal oven used for orbital cure of the boom. Results show that -12°C is the lowest temperature required for cure of the ROC™ resin systems.
Technical Paper

“Quiet” Aspects of the Pratt & Whitney Aircraft JT15D Turbofan

1973-02-01
730289
This paper describes the engine design details of the Pratt & Whitney JT15D-1 engine as related to noise generation. Design principles and factors contributing to the very low-noise levels on the Cessna Citation aircraft are illustrated. Noise testing experiences and data from static tests on the United Aircraft of Canada Ltd. (UACL) flight test aircraft and from both static and flight tests on the Citation aircraft are discussed. Lessons learned from these tests and some future probabilities are outlined.
Technical Paper

“Posture and Gait Control Enhancement Using Dermal Optical Sensitivity”

2004-07-19
2004-01-2484
Posture and gait controls underlie the fundamental physical and cognitive human factors necessary for astronauts’ safety and performance in Space. This central subsystem is adversely affected when exposed to an extreme or hostile environment. A specific stimulation, using dermal optical sensitivity, can be provided to the central nervous system to counteract peripheral stimulations due to microgravity as well as other negative stressors. We believe using dermal optical sensitivity-based stimulation can be key in the performance enhancement necessary to ensure human based space mission viability and success.
Technical Paper

“Personal Integrity” and Man-Machine Integration

1982-02-01
821348
A sense of “personal integrity” blocks pilot use of new information about how he thinks. Research on human performance under stress done over the past fifty years indicates increased rigidity and regression to earlier learned behavior in high stress, and in low Stress a shift in attention to any domestic situation or on the job controversy which is of higher stress than that of the job at hand, all without the pilot's knowledge. Informal surveys of commercial pilot training and commercial pilot attitudes towards these studies indicate that the study findings directly confront learned cultural responses. Pilot and trainer reactions prevent the information from being adequately investigated or formally taught. The findings are not written into training manuals and pilots who are informally given the information do not have adequate access to the knowledge when it is needed.
Technical Paper

“Pedestrian in the Loop”: An Approach Using Augmented Reality

2018-04-03
2018-01-1053
A large number of testing procedures have been developed to ensure vehicle safety in common and extreme driving situations. However, these conventional testing procedures are insufficient for testing autonomous vehicles. They have to handle unexpected scenarios with the same or less risk a human driver would take. Currently, safety related systems are not adequately tested, e.g. in collision avoidance scenarios with pedestrians. Examples are the change of pedestrian behaviour caused by interaction, environmental influences and personal aspects, which cannot be tested in real environments. It is proposed to use augmented reality techniques. This method can be seen as a new (Augmented) Pedestrian in the Loop testing procedure.
Technical Paper

“Next Generation” Means for Detecting Squeaks and Rattles in Instrument Panels

1997-05-20
972061
Engineers doing squeak and rattle testing of instrument panels (IP's) have successfully used large electrodynamic vibration systems to identify sources of squeaks and rattles (S&R's). Their successes led to demands to test more IP's, i.e., to increase throughput of IP's to reflect the many design, material, and/or manufacturing process changes that occur, and to do so at any stage of the development, production, or QA process. What is needed is a radically different and portable way to find S&R's in a fraction of the time and at lower capital cost without compromising S&R detection results.
Technical Paper

“Multi Vector” Field of View Design Tool

2004-03-08
2004-01-0380
A multi vector design tool to accurately predict instrument panel obscuration was developed to insure that critical legal displays in vehicles are not obscured. The concept provides for a computer generated light source shaped to replicate the human eyes. The light source is then projected onto a 3D math based arrangement and the resultant shadows are visible on the instrument panel surface and its displays. Design studios require criteria for the placement of the instrument cluster gages and displays, various controls, switches, and steering column stalks before an interior theme can be completed. Therefore, instrument panel obscuration and visibility must be determined early in the design process. The obscured areas are a function of the instrument panel surface, steering wheel rim, hub, spokes, and the location of the driver's eyes. This light source method allows engineers and designers the ability to quickly determine obscured areas.
Technical Paper

“Motion in FEA”: An Innovative Approach for More Physical and More Accurate Vehicle Dynamics Simulation

2012-04-16
2012-01-0762
Vehicle dynamics is a discipline of mechanical engineering that benefited of significant improvements thanks to the progress of computational engineering. Vehicle dynamics engineers are using CAE for the development of a vehicle with MBS and FEA. The concurrent use of these two technologies is a standard in the automotive industry. However the current simulation process is not fully efficient because local geometrical and material nonlinearities are not accurately modeled in classical MBS software. This paper introduces a methodology for vehicle dynamics simulation integrating MBS capabilities in one single nonlinear FEA environment enabling an accurate modeling of nonlinearity in vehicles.
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