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This paper presents demographic and static anthropometric data collected from a nationwide sample of truck drivers. Demographic data presented include age, driving experience, and type of truck driven. Anthropometric results showed that the sample of truck drivers was taller and heavier than the general U.S. population. Twenty-one (21) anthropometric measures are reported for males (N = 183) and females (N = 53), including body lengths, breadths, and circumferences.

This paper presents the sample selection rationale and data collection methodology used to collect truck driver anthropometric and work space data. A total of 241 drivers were measured (183 males and 58 females). Data were collected in eight cities nationwide, based on estimates of the number of drivers in each geographic region. A mobile laboratory was used to measure, among other things, body dimensions, arm reach envelopes, foot reach, seat position, eye position, knee position, and stomach-to-wheel clearance. Three buck configurations were used which varied the number of parameters adjusted by the subjects, including seat fore-aft, seat height, steering wheel angle, steering wheel fore-aft, and steering wheel vertical positions. Front and side photographs were made of each subject in his or her preferred seating configuration.

This paper reviews the history of heavy truck noise legislation in the U.S. Both legislative activity and the response of vehicle and engine manufacturers are described. The cost cycle experienced by manufacturers is also described. Over a period of time, the costs involved in meeting noise regulations are reduced without increasing truck noise levels. Data is presented which shows that public complaints about truck noise are often related to modified vehicle exhaust systems. The data shows that modified exhaust systems have an especially severe effect on compression brake noise. Additional results suggest that some trucks with extensively modified exhaust systems may be able to pass the in-use noise standard.

Many areas of the world are in various stages of development which frequently includes a rapid increase in the motor vehicle population. As a result, some areas are beginning to show the effect of increased motor vehicle use on air pollution. The vehicle's contribution to California's air pollution has long been recognized and studied, and measures have been implemented to reduce emissions from motor vehicles. The history of light duty vehicle emission control in the South Coast Air Basin of California is reviewed. Emission reductions achieved, current levels, projected future emissions and the need for further emissions reductions from light duty vehicles are discussed. For other areas of the world where motor vehicles contribute to air pollution, suggestions are made which can improve the effectiveness of emission control efforts; which should be consistent with political and economic realities, and efforts to achieve international harmonization of standards.

U.S. and Russian cooperation in the International Space Station (ISS) has been ongoing since the end of 1993. Joint agreements related to Extravehicular Activity (EVA) involve the full scope of hardware and operations used on-orbit and on the ground. Technical requirement studies, common hardware development, ground tests and flight experience are all combining to aid joint progress. The Shuttle-Mir missions are directly contributing to the level of hands-on experience which is so crucial to current and future ISS activities. Common goals and practical methods are aiding in overcoming minor technical differences to create real opportunities for mutual success. With shared vision, dedicated leadership and adequate resources, the future is bright.

The successful implementation of polycarbonate for automotive headlamp applications, required the development of specialized coatings. These coatings are required to offer superior ultraviolet as well as scratch resistance. Initially, silicone-based products were the only products available. However, in the last several years, alternative technologies have been developed including organic baking enamels and U.V. - Curable products. This paper will discuss the available technologies as well as the advantages and disadvantages of each. Future trends in lighting and coating advancements will also be highlighted.

Urban air mobility (UAM) is a fast-growing industry that utilizes electric vertical take-off and landing (eVTOL) technologies to operate in densely populated urban areas with limited space. However, atmospheric icing serves as a limitation to its operational envelope as in-flight icing can happen all year round anywhere around the globe. Since icing in smaller aviation systems is still an emerging topic, there is a necessity to study icing of eVTOL rotors specifically. Two rotor geometries were chosen for this study. A small 15-inch rotor was selected to illustrate a multirotor UAV drone, while a large 80-inch rotor was chosen to represent a UAM passenger aircraft. The ice accretion experiments were conducted in an icing wind tunnel on the small 15-inch rotor. The icing simulations were performed using FENSAP-ICE. The ice accretion simulations of the 15-inch rotor sections at –5 °C show a large, rather streamlined ice shape instead of the expected glaze ice characteristics.

Upon their arrival, Unmanned Autonomous Systems (UAS) brought with them many benefits for those involved in a military campaign. They can use such systems to reconnoiter dangerous areas, provide 24-hr aerial security surveillance for force protection purposes or even attack enemy targets all the while avoiding friendly human losses in the process. Unfortunately, these platforms also carry the inherent risk of being built on innately vulnerable cybernetic systems. From software which can be tampered with to either steal data, damage or even outright steal the aircraft, to the data networks used for communications which can be jammed or even eavesdropped on to gain access to sensible information. All this has the potential to turn the benefits of UAS into liabilities and although the last decade has seen great advances in the development of protection and countermeasures against the described threats and beyond the risk still endures.

Under AMRDEC's Aviation Multi-Platform Munition Program (AMPM) Science and Technology Program, a “Shadow Hawk” munition (developed by Lockheed Martin Missiles and Fire Control) was commanded and released using AMRDEC's Universal Test Pod (UTP) and successfully impacted the designated ground target. The UTP program pioneered usage of OSD Unmanned Aircraft System (UAS) Control Segment (UCS) Architecture Mission Effects Sub-domain and standardized STANAG 4586 weapon control messages that formed the basis of OSD's Data Link IP (draft). The UTP employed the Universal Armaments Interface (UAI) implemented in the UTP stores management system, which provides a developmental universal, open-architecture weapon interface. This was the first demonstration of a precision-guided weapon released from a RQ-7B Shadow UAS.

In-flight atmospheric icing is a significant threat to the use of unmanned aerial vehicles (UAVs) in adverse weather. The propeller of the UAV is especially sensitive to icing conditions, as it accumulates ice at a faster rate than the wings of the UAVs. Ice protection systems can be developed to counteract the danger of icing on the propeller of UAVs. In this study, the influence of different meteorological conditions on a propeller of a UAV is analyzed for a UAV with a wingspan of a few meters. The ice accretion and the performance degradation and the required anti-icing heat fluxes have been calculated using numerical methods with ANSYS FENSAP-ICE. This analysis has been used to evaluate the critical conditions for the operation of a UAV in icing conditions and the design of a thermal IPS system for a propeller. The highest ice mass has been found at a temperature of −10 °C and an MVD of 20 μm in intermittent maximum icing conditions.

Icing is a severe hazard to aircraft and in particular to unmanned aerial vehicles (UAVs). One important activity to understand icing risks is the prediction of ice shapes with simulation tools. Nowadays, several icing computational fluid dynamic (CFD) models exist. Most of these methods have been originally developed for manned aircraft purposes at relatively high Reynolds numbers. In contrast, typical UAV applications experience Reynolds numbers an order of magnitude lower, due to the smaller airframe size and lower airspeeds. This work proposes a set of experimental ice shapes that can serve as validation data for ice prediction methods at low Reynolds numbers. Three ice shapes have been collected at different temperatures during an experimental icing wind tunnel campaign. The obtained ice shapes represent wet (glaze ice, −2 °C), mixed (−4 °C), and dry (rime ice, −10 °C) ice growth regimes. The Reynolds number is between Re=5.6…6.0×105, depending on the temperature.

Atmospheric icing is a key challenge to the operational envelope of medium-sized fixed-wing UAVs. Today, several numeric icing codes exist, that all have been developed for general aviation applications. UAVs with wingspans of several meters typically operate at Reynolds numbers an order of magnitude lower than commercial and military aircraft. Therefore, the question arises to what extent the existing codes can be applied for low-Reynolds UAV applications to predict ice accretion. This paper describes an experimental campaign at the Cranfield icing wind tunnel on a RG-15 and a NREL S826 airfoil at low velocities (25-40m/s). Three meteorological icing conditions have been selected to represent the main ice typologies: rime, glaze, and mixed ice. Each case has been run at least twice in order to assess the repeatability of the experiments. Manual ice shape tracings have been taken at three spanwise locations for each icing case.

As part of the complete solution to deal with atmospheric in-flight icing on unmanned aerial vehicles (UAV), a path planner is a valuable tool for finding an optimal path for accomplishing UAV missions. When considering icing conditions, the planner manages areas with icing risk. Together with an electro-thermal ice protection system (IPS), the path planner can optimize energy consumption by comparing energy consumed flying through the cloud or around it, as the UAV can now more safely pass through the ice. The UAV’s aerodynamic stability is also considered by meeting lift requirements, producing enough thrust, and having battery capacity left. These are constraints in the planner to ensure that the UAV can complete its mission. Benchmark icing cases are constructed to validate that the path planner performs as intended.

Atmospheric in-flight icing poses a challenge to all aircraft including unmanned aerial vehicles (UAVs). Aircraft should avoid icing conditions unless they have ways of mitigating the negative effects of icing, e.g., if they are equipped with an ice protection system (IPS). When de-icing systems are used, a certain amount of ice is allowed to accumulate before it is removed. This intercycle ice deteriorates the aerodynamics by reducing the lift, adding mass, and increasing the drag. This study combines the energy that is required to compensate for the added drag of intercycle ice shapes with the energy required for a wing IPS and compares the energy needs for different IPS operations. Two different kinds of intercycle ice shapes are simulated numerically using FENSAP-ICE, one ice shape that would accrete on an unprotected wing and one ice shape that would accrete when using a parting strip, a continuously heated element at the leading edge.

In-flight icing can result in severe aerodynamic performance penalties for unmanned aerial vehicles. It is therefore important to understand to which extent ice will build up on fixed-wing unmanned aerial vehicles wings and empennages, namely rudder and elevator, and how this ice will impact the aerodynamic performance and limits the flight envelope. This work investigates numerically icing effects on wing and empennage over a wide range of icing parameters. This is conducted using the icing CFD code FENSAP-ICE on the Maritime Robotics PX-31 Falk UAV. Therefore, the 2D profiles of these airfoils, which are RG-15 for the wing and SD8020 for rudder and elevator, are investigated. The investigated angles of attack are between –5° and 14° in 0.5° increments. Furthermore, the icing conditions are chosen according to the FAA CS 25 Appendix C for continuous maximum and intermittent maximum icing.

The Nucleation In ForesTs (NIFTY) campaign was conducted in the Morgan Monroe State Forest (MMSF) during the month of May 2008. The objectives of this campaign were to understand the principal mechanisms of nucleation, the limitations of nucleation and growth, the spatial extent of nucleation events, subsequent particle growth after nucleation in MMSF, and the link between particle nucleation and breakdown of the nocturnal boundary layer which enhances vertical mixing. This paper discusses the use of a UAV to perform selected aspects of this project, mission that was accomplished by a team of students during the campaign, and analysis of a crash which concluded the mission.

New trends in aircraft design suggest that there may be a mission advantage to placing the aircraft engine in backwards for applications in Unmanned Combat Air Vehicles (UCAV’s). These aircraft use stealth as their primary defense. Stealth is, therefore, of utmost importance leaving aerodynamics to take a lower priority in the design process. The combination of a flying wing, planform shape, airfoil and stability and control of these aircraft limit the maximum lift coefficient of the vehicle to a relatively low value. Increasing the maximum lift coefficient can be achieved by use of thrust vectoring forward of the center of gravity. This suggests an internal layout that places the engine flow opposite to that of the free stream. This design is currently being developed in an Embry-Riddle Aeronautical University undergraduate design course.

The Uniform Detection Characteristic (UDC) locus circumscribes a region in front of a vehicle at which the luminance requirement for detecting a roadway obstacle is met by the vehicle's headlamp system. Algorithms take into account variables that are not typically addressed by traditional (isolux) roadway illumination methods. The variables that can be treated include: obstacle size, coloration or reflectance characteristics; a driver's state of expectancy, age-related changes in visual sensitivity, and adaptation levels elevated by ambient light. The discernibility locus defines the distance at which a detection criterion, the luminance sensitivity threshold, is satisfied for moving or stationary obstacles. The locus protocol can be used for grading the effectiveness of lighting systems on specific vehicles, or for forensic investigation of nighttime automobile accidents

In today’s automobile industry where BS6 emission is posing a high challenge for aggregate development, cost control and with limited timeline. The main target is to provide the cooling system to have less impact on the in terms of cost, weight and to meet the challenging engineering requirement. Thus, the frugal engineering comes into the picture. This paper shows the application of thermosyphon principle for UDM injector cooling thereby reducing the rotation parts and power consumption such as an electric pump. Thermosyphon is a method of passive heat exchange and is based on natural convection, which circulates a fluid without the necessity of a mechanical or electric pump. The natural convection of the liquid commences when heat transfer to the liquid gives rise to a temperature difference from one side of the loop to the other.

Legacy electronic control units are, nowadays, required to implement cybersecurity measures, but they often do not have all the elements that are necessary to realize industry-standard cybersecurity controls. For example, they may not have hardware cryptographic accelerators, segregated areas of memory for storing keys, or one-time programmable memory areas. Such systems must still be protected with a sufficient level of rigor against attackers who wish to modify their operation or extract confidential information from them. A critical interface to defend is the Unified Diagnostics Service (UDS) interface which is used in many areas across the whole vehicle lifecycle. While the UDS service $27 (Security Access) has a reputation for poor cybersecurity, there is nothing inherent in the way it operates which prevents a secure access-control from being implemented.