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Autonomous vehicles have the potential to transform lives by providing transportation to a wider range of users. However, with this new method of transportation, user acceptance and comfort are critical for widespread adoption. This exploratory study aims to investigate what makes passengers uncomfortable in existing vehicles to inform the design of future autonomous vehicles. In order to predict what may impact user acceptance for a diverse rider population for future autonomous vehicles, it is important to understand what makes a broad range of passengers uncomfortable today. In this study, interviews were conducted for a total of 75 participants from three diverse groups, including 20 automotive engineering graduate students who are building an autonomous concept vehicle, 21 non-technical adults, and 34 senior citizens. The results revealed both topics which made different groups of passengers uncomfortable as well as how these varied between the groups.

The purpose of this research is to characterize the wear resistance of wheel treads made of polymeric woven and non-woven fabrics. Experimental research is used to characterize two wear mechanisms: (1) external wear due to large sliding between the tread and rocks, and (2) external wear due to small sliding between the tread and abrasive sand. Experimental setups include an abrasion tester and a small-scale merry-go-round where the tread is attached to a deformable rolling wheel. The wear resistance is characterized using various measures including, quantitatively, by the number of cycles to failure, and qualitatively, by micro-visual inspection of the fibers’ surface. This paper describes the issues related to each experiment and discusses the results obtained with different polymeric materials, fabric densities and sizes. The predominant wear mechanism is identified and should then be used as one of the criteria for further design of the tread.

The Waste and Hygiene Compartment will serve as the primary facility for metabolic waste management and personal hygiene on the United States segment of the International Space Station. The Compartment encloses the volume of two standard ISS racks and will be installed into Node 3 after launch inside a Multipurpose Logistics Module on the Space Shuttle. Long duration space flight requires a departure from the established hygiene and waste disposal practices employed on the Space Shuttle. This paper describes requirements and a conceptual design for the Waste and Hygiene Compartment that are both logistically practical and acceptable to the crew.

In the next 20 years fully autonomous vehicles are expected to be in the market. The advance on their development is creating paradigm shifts on different automotive related research areas. Vehicle interiors design and human vehicle interaction are evolving to enable interaction flexibility inside the cars. However, most of today’s vehicle manufacturers’ autonomous car concepts maintain the steering wheel as a control element. While this approach allows the driver to take over the vehicle route if needed, it causes a constraint in the previously mentioned interaction flexibility. Other approaches, such as the one proposed by Google, enable interaction flexibility by removing the steering wheel and accelerator and brake pedals. However, this prevents the users to take control over the vehicle route if needed, not allowing them to make on-route spontaneous decisions, such as stopping at a specific point of interest.

Image segmentation has historically been a technique for analyzing terrain for military autonomous vehicles. One of the weaknesses of image segmentation from camera data is that it lacks depth information, and it can be affected by environment lighting. Light detection and ranging (LiDAR) is an emerging technology in image segmentation that is able to estimate distances to the objects it detects. One advantage of LiDAR is the ability to gather accurate distances regardless of day, night, shadows, or glare. This study examines LiDAR and camera image segmentation fusion to improve an advanced driver-assistance systems (ADAS) algorithm for off-road autonomous military vehicles. The volume of points generated by LiDAR provides the vehicle with distance and spatial data surrounding the vehicle.

A new life support approach is proposed for use on the International Space Station (ISS). This involves advanced technologies for water recovery and air revitalization, tested at the Johnson Space Center (JSC), including bioprocessing, reverse-osmosis and distillation, low power carbon dioxide removal, non-expendable trace contaminant control, and carbon dioxide reduction.

The application of virtual engineering methods can streamline the product design process through improved collaboration opportunities among the technical staff and facilitate additive manufacturing processes. A product digital twin can be created using the available computer-aided design and analytical mathematical models to numerically explore the current and future system performance based on operating cycles. The strategic decision to implement a digital twin is of interest to companies, whether the required financial and workforce resources will be worthwhile. In this paper, two metrics are introduced to assist management teams in evaluating the technology potential. The usefulness and time savings metrics will be presented with accompanying definitions. A case study highlights the usefulness metric for the “Deep Orange” prototype vehicle, an innovative off-road hybrid vehicle designed and fabricated at Clemson University.

Automotive drive-by-wire systems have enabled greater mobility options for individuals with physical disabilities. To further expand the driving paradigm, a need exists to consider an alternative vehicle steering mechanism to meet specific needs and constraints. In this study, a cellphone steering controller was investigated using a fixed-base driving simulator. The cellphone incorporated the direction control of the vehicle through roll motion, as well as the brake and throttle functionality through pitch motion, a design that can assist disabled drivers by excluding extensive arm and leg movements. Human test subjects evaluated the cellphone with conventional vehicle control strategy through a series of roadway maneuvers. Specifically, two distinctive driving situations were studied: a) obstacle avoidance test, and b) city road traveling test. A conventional steering wheel with self-centering force feedback tuning was used for all the driving events for comparison.

Spacecraft thermal control systems are essential to provide the necessary thermal environment for the crew and to ensure that the equipment functions adequately on space missions. The Ultralight Fabric Reflux Tube (UFRT) was developed by the Pacific Northwest National Laboratory as a lightweight radiator concept to be used on planetary surface-type missions (e.g., Moon, Mars). The UFRT consists of a thin-walled tube (acting as the fluid boundary), overwrapped with a low-mass ceramic fabric (acting as the primary pressure boundary). The tubes are placed in an array in the vertical position with the evaporators at the lower end. Heat is added to the evaporators, which vaporizes the working fluid. The vapor travels to the condenser end section and condenses on the inner wall of the thin-walled tube. The resulting latent heat is radiated to the environment. The fluid condensed on the tube wall is then returned to the evaporator by gravity.

Unmanned ground vehicles (UGVs) may encounter difficulties accommodating environmental uncertainties and system degradations during harsh conditions. However, human experience and onboard intelligence can may help mitigate such cases. Unfortunately, human operators have cognition limits when directly supervising multiple UGVs. Ideally, an automated decision aid can be designed that empowers the human operator to supervise the UGVs. In this paper, we consider a connected UGV platoon under cyber attacks that may disrupt safety and degrade performance. An observer-based resilient control strategy is designed to mitigate the effects of vehicle-to-vehicle (V2V) cyber attacks. In addition, each UGV generates both internal and external evaluations based on the platoons performance metrics. A cloud-based trust-based information management system collects these evaluations to detect abnormal UGV platoon behaviors.

In the United States and worldwide, 38,824 and 1.35 million people were killed in vehicle crashes during 2020. These statistics are tragic and indicative of an on-going public health crisis centered on automobiles and other ground transportation solutions. Although the long-term US vehicle fatality rate is slowly declining, it continues to be elevated compared to European countries. The introduction of vehicle safety systems and re-designed roadways has improved survivability and driving environment, but driver behavior has not been fully addressed. A non-confrontational approach is the evaluation of driver behavior using onboard sensors and computer algorithms to determine the vehicle’s “mistrust” level of the given operator and the safety of the individual operating the vehicle. This is an inversion of the classic human-machine trust paradigm in which the human evaluates whether the machine can safely operate in an automated fashion.

A Plasma Air Decontamination System (PADS) is being developed by ORBITEC for trace contaminant control in spacecraft cabin air, based on non-thermal, atmospheric pressure plasma discharges that generate various highly reactive species that can react with and break down trace air contaminants. It uses a simple and modular design, and may be scaled up or down to meet the requirements of different applications. The prototype PADS reactor has successfully demonstrated removal of ammonia and other selected volatile organic carbons from air, including acetone, ethylbenzene, methane, and methylene chloride. It has the potential to replace the existing high-temperature catalytic oxidizers.

Space-faring crews must have safe breathing air throughout their missions to ensure adequate performance and good health. Toxicological assessment of air quality depends on applicable air-quality standards, measurements of pollutant concentrations, and crew reports of air quality. Samples of air were obtained during ingress and egress of the Zarya and Unity modules on missions 2A and 2A.1. The results from 2A suggest that trace pollutants were at safe levels and that there was good air exchange between the modules. Results from the 2A.1 flight also showed that trace pollutants were at acceptable concentrations; however, there was evidence of inadequate mixing between the modules during the hatch-open operations. Furthermore, the 2A.1 crew reported after the flight that the air quality seemed to cause symptoms during their operations in Zarya, particularly when more than one crewmember was working inside open panels for some time.

Space-faring crews must have safe breathing air throughout their missions to ensure adequate performance and good health. Toxicological assessment of air quality depends on the standards that define acceptable air quality, measurements of pollutant levels during the flight, and reports from the crew on their in-flight perceptions of air quality. Air samples returned from ISS on flights 8A, UF2, 9A, and 11A were analyzed for trace pollutants. On average, the air during this period of operations was safe for human respiration. However, about 3 hours into the regeneration of 2 Metox canisters in the U.S. airlock on 20 February 2002 the crew reported an intolerable odor that caused them to stop the regeneration, take refuge in the Russian segment, and scrub air in the U.S. segment for 30 hours. Analytical data from grab samples taken during the incident showed that the pollutants released were characteristic of nominal air pollutants, but were present in much higher concentrations.

There are many sources of air pollution that can threaten air quality during space missions. The International Space Station (ISS) is an extremely complex platform that depends on a multi-tiered strategy to control the risk of excessive air pollution. During the seven missions surveyed by this report, the ISS atmosphere was in a safe, steady-state condition; however, there were minor loads added as new modules were attached. There was a series of leaks of octafluoropropane, which is not directly toxic to humans, but did cause changes in air purification operations that disrupted the steady state condition. In addition, off-nominal regeneration of metal oxide canisters used during extravehicular activity caused a serious pollution incident.

As planetary suit and planetary life support systems develop, specific design inputs for each system relate to a presently unanswered question concerning operational concepts: What distance can be considered a safe walking distance for a suited crew member exploring the surface of the Moon to ‘walkback’ to the habitat in the event of a rover breakdown, taking into consideration the planned extravehicular activity (EVA) tasks as well as the possible traverse back to the habitat? It has been assumed, based on Apollo program experience, that 10 kilometers (6.2 mi) will be the maximum EVA excursion distance from the lander or habitat to ensure the crew member's safe return to the habitat in the event of a rover failure. To investigate the feasibility of performing a suited 10 km walkback, NASA-JSC assembled a multi-disciplinary team to design and implement the ‘Lunar Walkback Test’.

As space hardware continues to grow in complexity, the demands on crews expected to be able to operate and maintain this equipment continue to grow. In terms of the International Space Station, the demands on the crew have been further increased by the reduction in crew capacity from the originally planned seven members down to three. This situation has prompted the need to find new ways of training that can meet these demands. In particular, just-in-time training techniques promise to enable crew members to correctly execute procedures that they have never performed before on equipment that they are only marginally familiar with or perhaps have never even seen before. To enable crews to work with unfamiliar procedures or equipment, we believe that it is necessary to employ a highly visual approach to convey the complex spatial information that is often involved.

The International Space Station (ISS) Active Thermal Control System (ATCS) (Ref. 1,2) has changed over the past several years to address problems and to improve its assembly and operation on-orbit. This paper captures the ways in which the Internal (I) ATCS and External (E) ATCS have changed design characteristics and operations both for the system currently operating on-orbit and the new elements of the system that are about to be added and/or activated. The rationale for changes in ATCS design, assembly and operation will provide insights into the lessons learned during ATCS development. The state of the assembly of the integrated ATCS will be presented to provide a status of the build-up of the system. The capabilities of the on-orbit system will be presented with a summary of the elements of the ISS ATCS that are functional on-orbit plus the plans for launch of remaining parts of the integrated ISS ATCS.

For over 40 years, NASA has been putting humans safely into space in part by minimizing microbial risks to crew members. Success of the program to minimize such risks has resulted from a combination of engineering and design controls as well as active monitoring of the crew, food, water, hardware, and spacecraft interior. The evolution of engineering and design controls is exemplified by the implementation of HEPA filters for air treatment, antimicrobial surface materials, and the disinfection regimen currently used on board the International Space Station. Data from spaceflight missions confirm the effectiveness of current measures; however, fluctuations in microbial concentrations and trends in contamination events suggest the need for continued diligence in monitoring and evaluation as well as further improvements in engineering systems. The knowledge of microbial controls and monitoring from assessments of past missions will be critical in driving the design of future spacecraft.

Electrification of off-road vehicle powertrains can increase mobility, improve energy efficiency, and enable new utility by providing high amounts of electrical power for auxiliary devices. These vehicles often operate in extreme temperature conditions at low ground speeds and high power levels while also having significant cooling airpath restrictions. The restrictions are a consequence of having grilles and/or louvers in the airpath to prevent damage from the operating environment. Moreover, the maximum operating temperatures for high voltage electrical components, like batteries, motors, and power-electronics, can be significantly lower than those of the internal combustion engine. Rejecting heat at a lower temperature gradient requires higher flow rates of air for effective heat exchange to the operating environment at extreme temperature conditions.