Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “TRANSPORT VEHICLE”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2

Design of an autonomous teleoperated cargo transporting vehicle for lunar base operations

At the turn of the century NASA plans to begin construction of a lunar base. The base will likely consist of developed areas (i.e., habitation, laboratory, landing and launching sites, power plant) separated from each other due to safety considerations. The Self-Repositioning Track Vehicle (SRTV) was designed to transport cargo between these base facilities. The SRTV operates by using two robotic arms to raise and position segments of track upon which the vehicle travels. The SRTV utilizes the semiautonomous mobility (SAM) method of teleoperation; actuator-controlled interlocking track sections; two robotic arms each with five degrees of freedom; and these materials: titanium for structural members and aluminum for shell members, with the possible use of light-weight, high-strength composites.

Holt, James↗

Expendable launch vehicle transportation for the space station

Logistics transportation will be a critical element in determining the Space Station Freedom's level of productivity and possible evolutionary options. The current program utilizes the Space Shuttle as the only logistics support vehicle. Augmentation of the total transportation capability by expendable launch vehicles (ELVs) may be required to meet demanding requirements and provide for enhanced manifest flexibility. The total operational concept from ground operations to final return of support hardware or its disposal is required to determine the ELV's benefits and impacts to the Space Station Freedom program. The characteristics of potential medium and large class ELVs planned to be available in the mid-1990's (both U.S. and international partners' vehicles) indicate a significant range of possible transportation systems with varying degrees of operational support capabilities. The options available for development of a support infrastructure in terms of launch vehicles, logistics carriers, transfer vehicles, and return systems is discussed.

Corban, Robert R.↗

Advanced earth-to-orbit transportation vehicles and their propulsion systems

This paper identifies some of the advanced transportation systems and their associated propulsion systems being considered by MSFC for near-term missions (1980-1990), future missions (1990-2000), and far-term missions (post 2000). The near-term launch-vehicle considerations center around the growth Shuttle and the Shuttle-derived Heavy-Lift Launch Vehicle (HLLV) systems. The future and far-term considerations support the development of larger more advanced transportation systems. In such cases, the changing nature of the propulsion requirements needed by the launch vehicle are identified. The evolvement of chemical propulsion launch vehicles into the far future is prognosticated, and where applicable from a launch vehicle or propulsion viewpoint, orbit transfer vehicles are discussed.

Shelton, B. W.↗

New fireworthy composites for use in transportation vehicles

This paper presents an overview of certain aspects of the evaluation of the fireworthiness of air transport interiors. It examines some technical opportunities that are available today through the modification of aircraft interior subsystem components, modifications that may reasonably be expected to provide improvements in aircraft fire safety. These modifications have the potential of reducing the rate of fire growth, with a consequent reduction of heat, toxic gas, and smoke emission throughout the habitable interior of an aircraft, whatever the initial source of the fire. It is shown that these new materials modifications reduce the fire hazard not only because of their unique ablative properties, which help to contain or isolate the fire source, but also because there is a significant reduction in their characteristic flame spread, heat release, and smoke and toxic gas emissions.

Parker, J. A.↗

Future space transportation vehicles - A NASA perspective

NASA has conducted extensive analyses of several scenarios of potential payload applications in an attempt to project future space transportation capability requirements. Of particular concern is the development of increasingly capable launch system. The enhancement of the manned STS with a heavy liftcargo launch vehicle which would utilize Shuttle technology to provide an unmanned cargo version of the Shuttle is also being addressed.

Branscome, Darrell R.↗

Light-Duty Vehicle Transportation Policy and Implication on Greenhouse Gas Emissions

The transportation sector accounts for 16% of global greenhouse gas (GHG) emissions and is under formidable pressure to decarbonize. With a growing number of countries making commitments to achieve carbon neutrality or “net-zero” emissions within the next few decades, it is imperative for transportation researchers and policymakers to understand the viable pathways towards achieving carbon neutrality for light-duty transport. This chapter discusses the transportation policies and GHG emissions of the three largest markets in the world—the U.S., China, and the European Union. The life cycle GHG emissions of various vehicle technologies are evaluated while highlighting the regional and temporal differences. We then use market penetration and fleet models, developed specifically for each market, to comprehensively assess the light-duty transport energy demand and GHG emissions under various scenarios. The modeling results show that battery electric vehicles (BEVs) will increase in market share, but internal combustion engine vehicles (ICEV) will continue to dominate the passenger vehicle stock in the next 20 years under most scenarios. Improving ICEV efficiency can play a critical role in meeting GHG regulations in the near- and medium-term. BEVs, whose GHG emissions are highly dependent on the source of electricity generation, will play an essential role in the long-term as the electric grid becomes cleaner. In summary, transportation policies should be technology agnostic and consider emissions based on the whole life cycle. Moreover, a holistic approach to reducing transportation GHG emissions is key to achieving global environmental goals.

Ou, Shawn↗

Limiting performance of ground transportation vehicles subject to transient loading

A computational approach to determining the limiting performance of vehicles subject to transient disturbances based on response variable criteria is set forth. For the purposes of a limiting performance study, the transportation system dynamics are described using second- or first-order equations in which the sought for quantity is a vector of time-varying functions called control or isolator forces that have replaced portions of the physical system. Computations are performed as a linear programming problem. As an example of the limiting performance of vehicles in protecting passengers or cargo under crash conditions, the problem of lading damage of a rail vehicle that is struck by another vehicle is considered.

Pilkey, W. D.↗

Initial Validation of Robotic Operations for In-Space Assembly of a Large Solar Electric Propulsion Transport Vehicle

Developing a capability for the assembly of large space structures has the potential to increase the capabilities and performance of future space missions and spacecraft while reducing their cost. One such application is a megawatt-class solar electric propulsion (SEP) tug, representing a critical transportation ability for the NASA lunar, Mars, and solar system exploration missions. A series of robotic assembly experiments were recently completed at Langley Research Center (LaRC) that demonstrate most of the assembly steps for the SEP tug concept. The assembly experiments used a core set of robotic capabilities: long-reach manipulation and dexterous manipulation. This paper describes cross-cutting capabilities and technologies for in-space assembly (ISA), applies the ISA approach to a SEP tug, describes the design and development of two assembly demonstration concepts, and summarizes results of two sets of assembly experiments that validate the SEP tug assembly steps.

Komendera, Erik E.↗

Comparative vibration environments of transportation vehicles

Measured vibration data are presented for a number of air and surface vehicles. Consideration is given to the importance of direction effects; of vehicle operating modes such as takeoff, cruise, and landing; and of measurement location on the level and frequency of the measurements. Various physical measurement units or descriptors are used to quantify and compare the data. Results suggest the range of vibration associated with a particular mode of transportation and illustrate the comparative levels in terms of each of the descriptors. Collectively, the results form a data base which may be useful in assessing the ride of existing or future systems relative to vehicles in current operation. In addition, subjective response data obtained from vibration simulator studies are presented to illustrate human response characteristics as well as to indicate a laboratory approach for the development of ride-quality criteria.

Stephens, D. G.↗

Design Study of a Nuclear-Electric Transport Vehicle for Ice Giant Missions

Nuclear-electric propulsion, in which a nuclear reactor is used to power high specific-impulse ion thrusters for propulsion, is a promising method for such applications as missions to the ice giants Uranus and Neptune, identified as targets of high science value in the most recent NASA Decadal Survey of Planetary Science. Until recently, however, this has required a lightweight space nuclear power system that has yet to be designed. NASA has recently been developing the “Kilopower” nuclear reactor as a power source for future exploration missions, with a 1-kW prototype recently tested under the KRUSTY program. We utilized a next-generation Kilopower reactor to design a transportation system for missions to the ice giant planets. The mission objectives were to carry a payload of 1164 kg, comprising a lander/hopper vehicle to be delivered to explore the moon or moons of the target ice giant, along with atmospheric probes to drop into the atmosphere, plus 188 kg of science instrumentation on the spacecraft itself.

nuclear electric propulsion↗

Expendable launch vehicle transportation for the Space Station

ELVs are presently evaluated as major components of the NASA Space Station's logistics transportation system, augmenting the cargo capacity of the Space Shuttle in support of Station productivity and operational flexibility. The ELVs in question are the Delta II, Atlas II, Titan III, Titan IV, Shuttle-C (unmanned cargo development), European Ariane 5, and Japanese H-II, as well as smaller launch vehicles and OTVs. Early definition of ELV program impacts will preclude the potentially excessive costs of future Space Station modifications.

Corban, Robert R.↗

Low Noise Cruise Efficient Short Take-Off and Landing Transport Vehicle Study

The saturation of the airspace around current airports combined with increasingly stringent community noise limits represents a serious impediment to growth in world aviation travel. Breakthrough concepts that both increase throughput and reduce noise impacts are required to enable growth in aviation markets. Concepts with a 25 year horizon must facilitate a 4x increase in air travel while simultaneously meeting community noise constraints. Attacking these horizon issues holistically is the concept study of a Cruise Efficient Short Take-Off and Landing (CESTOL) high subsonic transport under the NASA's Revolutionary Systems Concepts for Aeronautics (RSCA) project. The concept is a high-lift capable airframe with a partially embedded distributed propulsion system that takes a synergistic approach in propulsion-airframe-integration (PAI) by fully integrating the airframe and propulsion systems to achieve the benefits of both low-noise short take-off and landing (STOL) operations and efficient high speed cruise. This paper presents a summary of the recent study of a distributed propulsion/airframe configuration that provides low-noise STOL operation to enable 24-hour use of the untapped regional and city center airports to increase the capacity of the overall airspace while still maintaining efficient high subsonic cruise flight capability.

Kim, Hyun D.↗

Opportunities for structural improvements for an advanced supersonic transport vehicle

The superplastically formed diffusion-bonded (SPF/DB) program has developed successfully and far enough to recommend that a major structural program to validate the weight and cost of SPF/DB sandwich titanium structure should be initiated. The NASA Langley study of wing and fuselage SPF/DB sandwich panels shows that this process is potentially structurally efficient. The Douglas SPF/DB expanded sandwich process that utilizes a welded core sheet that expands to face sheets proves to be very efficient. The theoretical weight optimization design charts for the wing and fuselage concepts were validated by small-scale tests. Mnay design applications were fabricated. Projecting the results of an SPF/DB sandwich airframe structure to a MDC AST design shows significant weight and cost savings. A 6 percent lower direct operating cost was calculated. A growth AST utilizing composites, metal matrices, and SPF/DB sandwich shows future promise for a post-1990 technology readiness. Titanium SPF/DB sandwich, compared to presently available aluminum structure, is superior for application to a Mach 2.2 supersonic transport.

Fischler, J. E.↗

System for measuring passenger reaction to transportation-vehicle vibration

Equipment is capable of measuring frequencies from 0 to 50 Hz and is portable, light, inexpensive, and easily adaptable to field operations. System could be used in situations where it is necessary to record simultaneously subject response to other types of physical measurement or stimuli, such as temperature, noise, or pressure.

Clevenson, S. A.↗

Aerodynamic braking of high speed ground transportation vehicles.

The drag effectiveness of aerodynamic brakes arranged in series on a train-like vehicle was investigated. Fixed- and moving-model testing techniques were used in order to determine the importance of proper vehicle-ground interference simulation. Fixed-model tests were carried out on a sting-mounted model: alone; with a fixed ground plane; and in proximity to an image model. Moving-model tests were conducted in a vertical slide-wire facility with and without a ground plane. Results from investigations of one brake configuration are presented which show the effect of the number of brakes in the set and of spacing between brakes.

Marte, J. E.↗

Transportation vehicle energy intensities. A joint DOT/NASA reference paper

A compilation of data on the energy consumption of air and ground vehicles is presented. The ratio BTU/ASM, British Thermal Units/Available Seat Mile, is used to express vehicle energy intensiveness, and related to the energy consumed directly in producing seat-mile or ton-mile productivity. Data is presented on passenger and freight vehicles which are in current use or which are about to enter service, and advanced vehicles which may be operational in the 1980's and beyond. For the advanced vehicles, an estimate is given of the date of initial operational service, and the performance characteristics. Other key considerations in interpreting energy intensiveness for a given mode are discussed, such as: load factors, operations, overhead energy consumption, and energy investments in new structure and equipment.

Mascy, A. C.↗