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Containers, although welcomed by the air freight industry, have been received with something less than enthusiasm by the user. Although the advantages of containers to the air freighter are real, those quoted to the user are frequently nonexistant. The sole real benefit, namely, reduced cost, must be passed on to the user. Costs may be cut only when customs clearance is at destination rather than at the port of entry and containers have intermodal capability. Further, airlines must change their attitudes and rulings and offer price incentives for reductions in the number of pieces shipped and the use of standard containers. Present preferential commodity rates must be scrapped.

The technical design and development of a new product is only one step in the long chain of events between the time that an unfulfilled customer need has been identified and a product to fulfill that need is finally sold and serviced. This paper attempts to provide the automotive engineer with an overview of the total procedure for marketing a new product-from product inception to final sale. Specifically, this paper analyzes the evolution of the sunroof option at Chrysler Corp. from the earliest recognition of the need for a product to replace declining convertible sales through to the selection of the advertising theme used to promote the sunroof.

The time is now for shipper and air carrier to maximize profitability through extensive employment of the air freight concept. Better understanding by both parties of the Total Materials Management theory, i.e., the tradeoffs to air cost, is the key to vastly improved utilization of The Flying Truck.

The technical feasibility of constructing and operating maglev vehicles at speeds of 250−300 mph has been amply demonstrated and is accepted here as a reality. In this paper, the markets into which passenger-or freight-carrying systems based on this technology can be introduced with economic reasonableness are evaluated. The characteristics and capabilities (particularly the capacity and comparative costs) of the system are enumerated and discussed from the points of view of the passengers, the airlines (as potential operators), and the traveling public. It is shown that if the system is integrated into the existing transportation system as a supplement to the airline system, it meets the criteria required for the introduction of any new product or service into a market. The financial enhancement of the maglev system resulting from the use of trunk routes with feeder lines diverging to various ultimate destinations becomes an extremely important consideration.

A main challenge when developing next generation architectures for automated driving ECUs is to guarantee reliable functionality. Today’s fail safe systems will not be able to handle electronic failures due to the missing “mechanical” fallback or the intervening driver. This means, fail operational based on redundancy is an essential part for improving the functional safety, especially in safety-related braking and steering systems. The 2-out-of-2 Diagnostic Fail Safe (2oo2DFS) system is a promising approach to realize redundancy with manageable costs. In this contribution, we evaluate the reliability of this concept for a symmetric and an asymmetric Electronic Power Steering (EPS) ECU. For this, we use a Markov chain model as a typical method for analyzing the reliability and Mean Time To Failure (MTTF) in majority redundancy approaches. As a basis, the failure rates of the used components and the microcontroller are considered.

This paper shows the place of Markov modeling in the spectrum of modeling tools and explains its benefits and limitations. It introduces the basic components of the model, and answers the questions WHY and WHEN to use Markov modeling. It provides the outline of several different types of Markov models and shows the results of Markov modeling. A process flow chart, a step-by-step procedure, and two examples are provided to facilitate the use of Markov modeling. Finally, this paper introduces the software tool used to perform Markov modeling.

Restraint system physical evidence is often examined during crash analysis to understand seat belt system use and effectiveness. As occupant restraint technologies have evolved over the years, the seat belt witness marks that occur in crashes have changed as well. Occupant loading has traditionally been the primary cause of marks on seat belt systems prior to pretensioners and force limiters. This research focused on newer seat belt systems equipped with force limiters and pretensioners, and how those features affect crash-induced witness marks. The front seat occupant seat belt systems studied contained both retractor pretensioners and retractor torsion-type force limiters. The crashes that were analyzed occurred on U.S. roadways where at least one airbag deployed. Distinct marks were located on the retractor, D-ring, latch plate or webbing surfaces resulting from the activation of pretensioners and/or force limiters.

In any consideration of long term (one or two years) human activities on Mars, it is imperative to evaluate the effects of the environment. There are two aspects of such environmental assessments: (1) hazardous parameters and (2) resource availability. This paper looks at both from the point of view of future human expeditions which include the requirement to explore Mars at some distance (e.g., several kilometers) from the landing site, and the ability to perform in situ measurements, physical and chemical analyses of surface and subsurface materials. Human activity on Mars clearly requires more support (food, water, air) than can be transported by a spacecraft. At the same time, resources for human protection from environmental hazards must be provided. This paper offers a discussion and analysis of these problems, based primarily on Mars fly-by, orbiter and lander data obtained in the 60's and 70's. The Viking orbiters and landers have been the most useful in that context.

Understanding the factors influencing crew performance under conditions of long-term isolation, confinement, high workload and elevated risk is an important prerequisite to the manned space exploration missions beyond low-Earth orbit that are planned under the new National Space Policy of the United States. Quantitatively tracking the performance of crews affected by those stressors is therefore crucial both during actual space missions and as part of precursor activities on the ground, such as those taking place at planetary-analog simulation facilities. During the summer of 2003, an experiment was carried out tracking the cognitive performance of the crew on board such a facility, the Mars Society’s “Flashline Mars Arctic Research Station” in the Canadian High Arctic. In addition to the self-administered computer-based testing, the crew’s daily activities were logged to enable the identification of external factors that might affect the observed performance.

Mars Base 10 was developed at the International Space University during an internship at NASA Ames Research Center. The underlying proposal was to develop innovative concepts for deployable and inflatable structures enabling permanent habitation on Mars for ten astronauts. The project was primarily conducted as an investigation for an analogue Mars base test bed for the Atacama Desert in Chile and for online virtual environment experiments (Spaceward Bound 2.0). The design presented in this paper takes into account all components of a mission to Mars with a focus on the surface habitat architecture.

This paper presents background information and describes operating experience with Mars Base Zero, a terrestrial analog of a Mars base situated in Fairbanks, Alaska. Mars Base Zero is the current stage in a progression from a vegetable garden to a fully closed system (Nauvik) that the International Space Exploration and Colonization Company (ISECCo) has undertaken. Mars Base Zero is an 80 m2 greenhouse, with 18m2 of living space attached. The primary goal is to determine the necessary size for Nauvik in order to support one to four people using current ISECCo techniques for growing food crops. In the spring of 2004 Mars Base Zero was planted, and in the fall of 2004, one subject, Ray Collins, was closed in the system for 39 days. The data from this closure indicates that, using ISECCo cropping techniques, Nauvik will need 150 m2 of crop area to support one person. While problems were encountered, the minimum goal of 30 days closure was exceeded.

Mars Exploration Rover (MER) mission launched two spacecraft to Mars in June and July of 2003 and landed two rovers on Mars in January 2004. A Heat Rejection System (HRS) based on a mechanically pumped single-phase liquid cooling system was used to reject heat from electronics to space during the seven months cruise from Earth to Mars. Even though most of this HRS design was similar to the system used on Mars Pathfinder in 1996, several key modifications were made in the MER HRS design. These included the heat exchanger used in removing the heat from electronics, design of venting system used to vent the liquid prior to Mars entry, inclusion of pressure transducer in the HRS, and the spacecraft radiator design. Extensive thermal/fluids modeling and analysis were performed on the MER HRS design to verify the performance and reliability of the system. The HRS design and performance was verified during the spacecraft system thermal vacuum tests.

NASA launched two rovers in June and July of 2003 as a part of the Mars Exploration Rover (MER) project. MER-A (Spirit) landed on Mars in Gusev Crater at 15 degrees South latitude and 175 degrees East longitude on January 4, 2004 (Squyres, et al., Dec. 2004). MER-B (Opportunity) landed on Mars in Terra Meridiani at 2 degrees South latitude and 354 degrees East longitude on January 25, 2004 (Squyres, et al., Aug. 2004). Both rovers have well exceeded their design lifetime (90 Sols) by more than a factor of 5. Spirit and Opportunity are still healthy and continue to execute their roving science missions at the time of this writing. This paper discusses rover flight thermal performance during the surface missions of both vehicles, covering roughly the time from the MER-A landing in late Southern Summer (aereocentric longitude, Ls = 328, Sol 1A) through the Southern Winter solstice (Ls = 90, Sol 255A) to nearly Southern Vernal equinox (Ls = 160, Sol 398A).

In January 2004, two Mars Exploration Rovers (MER) landed on the surface of Mars to begin their mission as robotic geologists. A year prior to these historic landings, both rovers and the spacecraft that delivered them to Mars, were completing a series of environmental tests in facilities at the Jet Propulsion Laboratory. This paper describes the test program undertaken to validate the thermal design and verify the workmanship integrity of both rovers and the spacecraft. The spacecraft, which contained the rover within the aeroshell, were tested in a 7.5 m diameter thermal vacuum chamber. Thermal balance was performed for the near earth (hot case) condition and for the near Mars (cold case) condition. A solar simulator was used to provide the solar boundary condition on the solar array. IR lamps were used to simulate the solar heat load on the aeroshell for the off-sun attitudes experienced by the spacecraft during its cruise to Mars.

The Mars Exploration Rovers (MER), were launched in June and July of 2003, respectively, and successfully landed on Mars in early and late January of 2004, respectively. The flight system architecture implemented many successful features of the Mars Pathfinder (MPF) system: A cruise stage that transported an entry vehicle that housed the Lander, which in turn, used airbags to cushion the Rover during the landing event. The initial thermal design approach focused on adopting the MPF design wherever possible, and then concentrating on the totally new Rover thermal design. Despite a fundamentally sound approach, there were several salient lessons learned. Some were due to differences from MPF, while others were caused by other means. These lessons sent a clear message: thermal design continues to be a system engineering activity. In each major flight system assembly, there were excellent examples of this recurring theme.

Designed by students and other volunteers from three universities in the U.S. and Australia, the Mars Gravity Biosatellite Program plans a launch of a small, unmanned research platform to support ground-breaking investigations in partial gravity physiology. This spinning spacecraft will provide “artificial gravity” at 0.38-g, the surface gravity of Mars. Onboard life support systems will support a payload of fifteen mice for a total mission duration of five weeks, culminating in reentry at the Woomera Protected Area in Australia. We present this international, multi-disciplinary, multi-institute program as a new model for both aerospace workforce development and public outreach.

This paper presents the work done by architecture students at the Institute for Architecture and Product Design at the University of Technology in Munich. The design studio based its studies on the M.A.R.S Mars Arctic Research Station on Devon Island by the Mars Society and the „Tuna Can“-Concept of the Mars Reference Mission by NASA. Main subjects of investigation were the greenhouse, the entrance/airlock situation, the work level and the living level. On the living level studies for the kitchen, hygiene facilities and the Crew Quarters have been done. The paper will explain the underlying design ideas and the students work will be illustrated by many drawings and model photographs.

This paper describes a simple concept for extracting a nitrogen-argon carrier gas mixture from the Martian atmosphere in-situ and compressing the gas to a pressure suitable for use in analytical experiments during exploration missions. Both the separation and compression processes are performed via adsorption. In addition to being a low-mass, low-volume, and virtually solid state unit, the process consumes little or no electrical power. Energy to perform work is taken from the environment using the daily temperature cycle. Such a device would also be a proof-of-concept technology for buffer gas generation for life support application on future human missions to Mars.

Mars landing vehicle descent propulsion is discussed in the light of the constraints of the mission, the environment, and the interfacing functions. The presence of a largely undefined, tenuous atmosphere is shown to produce a great variability of initial and boundary conditions for the propulsion phase of descent. The mission provides numerous subtle constraints of formidable importance to the propulsion implementation. The current requirement for prelaunch, in-situ, thermal sterilization is paramount among these. A significant, and unresolved, mission-related problem is that of the interaction of landing propulsion on the native environment. For a mission which has as its primary objective the investigation of the Mars environment, landing site alteration is a significant concern. The principal intersystem constraint is that of the flight path guidance logic choice.

The ultimate goal of human space exploration is to discover if life exists on other worlds, to understand the genesis and evolution of the universe and to learn to live on other planets. Mars offers the closest opportunity to pursue these goals realistically. The capabilities to define, design, develop, build, test, contract out, manufacture and operate new technologies are the means to achieve this set of goals. The purpose of this set of criteria is to evaluate mission design and exploration technology proposals to ensure that the means support the goals and do no obstruct them. This paper presents a comprehensive approach to evaluating complete Mars mission designs and partial designs. It begins from current theory and methodology of design problem definition. It proposes a method of evaluating if the mission design solution answers the problem definition.