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Technical Paper

U.S. Truck Driver Anthropometric and Truck Work Space Data Survey: Sample Selection and Methodology

1985-12-01
852315
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.
Technical Paper

U.S. Truck Driver Anthropometric and Truck Work Space Data Survey: Demographics and Static Anthropometrics

1985-12-01
852316
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.
Technical Paper

Compatibility of Automobile Interior Space With Low Aerodynamic Drag Body

1985-11-11
852287
The paper describes the compatibility of two contradictory factors among basic automobile design features through the development of an advanced research automobile. These factors are the interior space for passenger comfort and exterior shape for aerodynamic drag reduction. The basic design of the automobile is a fast-back front- drive car with packaging five passengers providing sufficient interior space resembling sedan. In consideration of safety regulations, the visibility and passenger comfort, body shape has been optimized by 1/5 scale model wind tunnel testing. Since engine cooling flow is one of the dominant factors among aerodynamic characteristics, resistance due to internal flow in the engine compartment are also explained. The drag coefficient of the advanced research automobile developed through aerodynamic studies was shown to be 0.25.
Technical Paper

Cost and Schedule Implications of Multinational Coproduction

1985-06-01
851150
Assesses cost and schedule implications of acquiring weapon systems using multinational coproduction by examining experiences accumulated in a large and diverse set of aerospace development and production programs. Describes and, where possible, quantifies marked U.S. and European differences in such areas as production scale, workforce policies, schedule philosophy, and manufacturing approaches, and discusses the implications of these differences for the the success of collaborative programs. Examines in detail the effects of coproduction on the cost and schedule of the F- 16 fighter aircraft program.
Technical Paper

Evolution of the Shuttle Extravehicular Mobility Unit's Life Support System

1985-07-01
851333
The Shuttle Extravehicular Mobility Unit (EMU) is an integral component in successful satellite salvaging operations. FMU evolution to its current operational status has occurred through implementation of carefully analyzed and thoroughly tested changes. The net result of these changes is known as the Block II FMU. This paper discusses the basic FMU system requirements, the philosophy used in the design of the Block I EMU, and the operation of the Life Support System (LSS); outlines the evolution of the Block II configuration; and briefly discusses future progression of the LSS. The Block II LSS configuration has improved serviceability between flights, simplified user operation, improved performance, decreased maintenance (by extending component life), and, most importantly, improved mean time between failures by a factor of fourteen.
Technical Paper

The Roles of Astronauts and Machines for Future Space Operations

1985-07-01
851332
The capabilities of remotely-operated telepresence systems for performing space operations are compared to direct human involvement via extravehicular activity (EVA). The varied roles of these approaches for future space missions are addressed, both individually and in combination. On-orbit activities are the basis for establishing typical tasks that will be required. These activities include servicing and construction operations on a manned space station, unmanned platforms, and other satellites. Techniques and concepts for accomplishing these tasks by means of EVA and remote systems are presented. Remotely operated systems controlled from the space station, with and without significant time delays, have been considered. Advantages and disadvantages of potential concepts are discussed. Laboratory testing and simulation of representative concepts of the remote systems and task performance by astronauts are discussed.
Technical Paper

Why Manned EVA?

1985-07-01
851331
Despite the fact that early STS planning did not include any provisions for manned Extravehicular Activity (EVA), the orbiter airlock and Extravehicular Mobility Units (EMU's) or “spacesuits” were eventually incorporated in the Space Transportation System. Events have amply demonstrated the value of manned EVA. It is concluded that EVA will continue to be required for STS missions and for the Space Station. The reasons that space vehicles may need servicing are presented, e.g., reliability/-MTBF, preventive maintenance, wear-out and degradation, damage, updating, and replacement. The functions that man can perform EVA are then reviewed, e.g., inspect/assess, reconfigure, repair, replace components, debris capture, checkout and verify. Some of the functions that man can perform easily in EVA but are difficult for machines/teleoperators are reviewed.
Technical Paper

Recent Shuttle EVA Operations and Experience

1985-07-01
851328
This paper describes the hardware used and the experience gained during the Space Shuttle extravehicular activities (EVAs) or “spacewalks” of 1984. Seven EVAs on four missions were conducted with objectives including hardware verification, satellite repair, hydrazine transfer, and satellite retrieval. The hardware used on these flights falls into two categories - general EVA hardware (e.g. the Manned Maneuvering Unit) and mission-unique hardware (e.g. apogee kick motor capture device, used to retrieve the WESTAR VI and PALAPA B-2 satellites). The successful completion of the mission objectives resulted in an increased knowledge of EVA operations and a broader base of Space Shuttle capabilities which are applicable to future operations.
Technical Paper

Testing EVA Equipment for Polar Orbit Operations

1985-07-01
851330
Polar orbit extravehicular activity (EVA) will expose EVA equipment to the conditions in which charging of Defense Meteorological Satellite Program (DMSP) satellites has been measured. Charging can occur when you have darkness, incident energetic electrons, and low neutralizing plasma density. Fluxes of precipitating keV to tens-of keV electrons, which also cause optical auroras, may be encountered in the high latitude auroral zone. In addition, a large body such as the Shuttle sweeps out the ambient ionospheric plasma to produce a cavity in its wake. Laboratory test results will be presented that confirm charging and subsequent arc discharge of EVA equipment material samples. Induced current and radiated radio frequency electromagnetic interference (EMI) were measured from the arc discharges. Such EMI could cause potentially dangerous EVA equipment anomalies. Ground tests of subsystems and the complete EVA equipment system are needed.
Technical Paper

Digital Control for Engine Bleed Air

1985-07-01
851316
As modern control systems become more demanding and complex and the optimum control algorithm becomes more elusive, it becomes obvious that the versatility of control algorithm construction and modification in software is far superior to analog circuit implementations. A digital microprocessor based electronic control system has been developed for temperature control of engine bleed air on the B-1B bomber. The Engine Bleed Air Control System (EBACS) provides pressurized, temperature controlled air to various subsystems on the aircraft. This paper addresses the unique approach used in controlling a bleed air system having major gain variations (over 500 to 1) and major system-element time-constant variations (over 5 to 1) within the flight envelope, while still maintaining specified response times and stability margins.
Technical Paper

Physiological Considerations for EVA in the Space Station Era

1985-07-01
851313
Extravehicular Activity (EVA) is an important part of the U.S. space program. The argument that EVA's are unnecessary or too dangerous has been refuted by the successes of contingency and planned EVA's. The recent successes in satellite maintenance and retrieval have demonstrated EVA's to be useful, practical, and safe. During the Space Station Program, crewmembers will be expected to perform more frequent EVA's. As in the past, the physiological factors must be integrated with operational and engineering considerations to achieve a safe, effective system. In past programs, we have been concerned with factors including metabolic work rates and extensive prebreathing methods to rid the body of bends-inducing nitrogen. In the Space Station Program, we are presented with frequent and varied EVA tasks which require that the hardware withstand repeated use, and that physiological limits not be exceeded.
Technical Paper

Preparing a Health Care Delivery System for Space Station

1985-07-01
851310
NASA's Space Station is viewed as the beginning of man's permanent presence in space. This paper presents the guidelines being developed by NASA's medical community in preparing a quality, permanent health care delivery system for Space Station. The guidelines will be driven by unique Space Station requirements such as mission duration, crew size, orbit altitude and inclination, EVA frequency and rescue capability. The approach will emphasize developing a health care system that is modular and flexible. It will also incorporate NASA's requirements for growth capability, commonality, maintainability, and advanced technology development. Goals include preventing unnecessary rescue attempts, as well as maintaining the health and safety of the crew. Proper planning will determine the levels of prevention, diagnosis, and treatment necessary to achieve these goals.
Technical Paper

Digital Controlled Closed Loop Air Cycle Development

1985-07-01
851319
The trend in Environmental Control System (ECS) design for military aircraft is towards the use of closed loop cooling systems with the use of microprocessors for ECS control. The use of a closed loop ECS can reduce energy extraction from the engines thereby resulting in a reduction in aircraft takeoff gross weight penalties and/or an increase in aircraft range. The other advantages over a conventional open loop system are that the vulnerability to the Chemical Biological (CB) threat is reduced and a more favorable thermal environment is provided for avionics. The purpose of this study was to develop a digital control system for a closed loop ECS and to demonstrate the controls in a breadboard laboratory test rig. The study showed that a practical approach to systems development includes use of the “EASY digital computer program for control law development, a hybrid analog/digital computer for software development and demonstration in a breadboard ECS.
Technical Paper

Space Applications of Nitinol Heat Engines

1985-07-01
851322
The Nitinol Heat Engine (NHE) uses a shape-memory alloy of nickel and titanium to convert thermal energy directly to mechanical power and through a generator, to electricity. An NHE was analyzed and designed to produce power from solar irradiation in space, with radiative cooling to a deep-space heat sink. A model NHE was built and tested in a space chamber simulating the radiation and space environment, and produced results agreeing with performance predictions. Other space NHE using Space Station waste heat are also discussed. Such space NHE are demonstrated to be cost-competitive with photovoltaic cells as a source for space power.
Technical Paper

The New Environmental Control System for the B-52 G/H Aircraft

1985-07-01
851320
ENVIRONMENTAL CONTROL SYSTEM (ECS) for the B-52 G/H Aircraft - The Boeing B-52 G/H aircraft uses precooled engine bleed air as a source for cabin pressurization and cabin, missile and avionics air conditioning. These systems are controlled by two solid state controllers which also contain built in self test and fault isolation. The ECS regulates the bleed air pressure and flow via an electrical signal from a cooling effect sensor in the avionics air supply. This flow control approach saves engine bleed air by not dumping excessive cold air into the avionics equipment and not over-cooling or overheating the two cabins or missiles. The missile conditioning system mixes cold and warm air to keep the missiles at the required temperature. The system also provides a “go-no-go” signal to the cabin to indicate “temperature readiness” of the missiles. The two cabins are separately temperature controlled through individual temperature selectors and controls.
Technical Paper

Heat Pipe Cooled Electronic Circuit Card as Applied to SEM FORMAT B Standard

1985-07-01
851317
Grumman developed, patented, and tested a heat pipe concept to increase the power dissipation capability of the SEM FORMAT B Standard Module. The systems integration concept approach in the development of the design was to: Provide a heat pipe module within the existing SEM FORMAT B form factor that would be interchangeable with the existing conduction module Utilize the short conduction path of the module Maintain the existing component mounting area Maintain thermal compatibility between the module and heat sink interface. Within the restraints of these objectives, the Grumman concept was shown to be feasible and proven to be capable of providing a power dissipation capability twice that of the existing conduction module.
Technical Paper

Environmental Control System Simulation using EASY5, as Applied to the F-14

1985-07-01
851318
The Naval Air Development Center has developed a thermal model of the F-14 Environmental Control System (ECS) using the EASY5 dynamic anaysis computer program. In addition to discussing the modeling effort, this paper also details several improvements made to the EASY5 program in an attempt to improve its accuracy, flexibility, and computational stability. Also highlighted is a simplified version of the F-14 EASY5 ECS model which is being used to conduct trade studies and to calculate the initial conditions required to run the EASYS program.
Technical Paper

Voice Interface for Transport Aircraft Cockpits

1982-02-01
820104
Increases in air traffic density, reductions in crew complement and the interface requirements of more computer processing and data storage on aircraft of the future threaten to overload the motor and visual channels of the flight crew. Considerable success has been achieved in developing devices to permit voice communication between people and computers in the past decade and possibilities exist for using this technology to maintain cockpit workload at manageable levels. Lockheed-Georgia is developing a voice interface system for caution-warning, data entry, information retrieval and systems control as part of an Advanced Flight Station Simulator program. Efforts are currently underway to define the proper requirements and applications for computer voice interface to achieve optimum interaction between people and machines under critical circumstances.
Technical Paper

HANDLING CHARACTERISTICS OF A SIMULATED TWIN TILT NACELLE V/STOL AIRCRAFT

1983-10-03
831549
The first government-conducted piloted flight simulation of the Grumman-designed twin turbofan-powered tilt-engine V/STOL aircraft (design 698) was conducted at NASA Ames Research Center. The aircraft is discussed with an emphasis on its unique hover characteristics. These characteristics include the adverse nonminimum phase that occurs in lateral and longitudinal translation, and the large attitude control power available. Both of these features are attributes of the control vanes (a Grumman-patented concept) buried in the fan exhaust flow. The simulation used the following NASA Ames Research Center facilities: The Vertical Motion Simulator with the interchangeable cab, the Sigma 8 computer, and the Computer-Generated Image system with a four-window display.
Technical Paper

Integrated Modelling Approaches in Advanced Cockpit Automation

1983-10-03
831543
With advances in display and control methods and recent developments in sensor and microelectronic technologies, the term automation, especially as it pertains to the cockpit of a tactical aircraft, has taken on a totally new dimension. No longer are we restricted to automation as it pertains to solely flight managment functions. Functions such as realtime situation assessment, tactics selection and trajectory control are all candidates for partial or total automation. In addition, adaptive vehicle subsystem reconfigurations as a function of tactical posture, onboard faults and ongoing emergencies are all within the purview of onboard automation. In order to realize these rather ambitious goals it is suggested that no one class of models is adequate in providing the necessary onboard intelligence to enhance overall performance and reduce workload.
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