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1973-02-01
Technical Paper
730930
R. F. Burchill, J. L. Frarey, D. S. Wilson
A technique is discussed for generating diagnostic information from the vibration signature of machinery in the high-frequency range (up to 100 kHz). The signal generation mechanism is discussed, as well as the diagnostically significant characteristics of the data and a method of extracting this information. Two specific cases are presented utilizing the techniques to illustrate its suitability for many of the common problems encountered in machinery.
1973-02-01
Technical Paper
730931
Dwain Kitchel, Kempton A. Smith
Predominant features of sound signatures can be related back to operational events occurring within components both for normal and failure mode operations. Engineering analysis permits establishment of quantized go, no-go, or caution parameters necessary to make readiness assessment decisions. The “Structure Borne Acoustics” test technique presented in this paper has outstanding potential for this work. Reliability includes accurate detection and diagnosis of the maximum number of faults, with an absolute minimum false alarm rate. Jet engine-bearing monitoring is one example of successful application.
1973-02-01
Technical Paper
730947
Wallace H. Deckert, Curt A. Holzhauser
The evaluation and evolution of direct jet lift V/STOL transport aircraft designs are discussed. The V/STOL transport design selected as an example is a lift-fan design that was evaluated as a candidate configuration for a possible future V/STOL research transport. The paper includes discussion of potential advanced V/STOL landing approach profiles as key design requirements for V/STOL aircraft, description and experimental results of an integrated propulsion/control system designed to achieve desired advanced V/STOL near-terminal operating capabilities, and results from evaluating V/STOL designs on piloted moving-base simulators. This paper discusses use of the piloted moving-base simulator as a design tool for evolving satisfactory V/STOL stabilization and propulsion/control systems. Included are problems and solutions identified during simulation of simultaneous decelerating/descent steep-curved landing approaches under instrument flight conditions.
1973-02-01
Technical Paper
730940
W. Henricks
A reverberant acoustic field is frequently used in ground testing when it is desired to generate a spacecraft vibration environment similar to that encountered in flight. The sound-pressure level specified to accomplish this is usually the same as the maximum expected flight fluctuating pressure level. Experience has shown this to be an inadequate way to specify reverberant ground test levels because of basic differences in the characteristics of the reverberant and flight fluctuating pressure fields. This paper reviews pertinent information on this subject that has recently been obtained from large upperstage space vehicles.
1973-02-01
Technical Paper
730884
J. M. Shults
This paper will discuss the procedures used for material selection that were developed and used for two Advanced Metallic Structures, Advanced Development Programs (AMS/ADP) sponsored by the Air Force Flight Dynamics Laboratory (AFFDL) under joint management and direction of AFFDL and the Air Force Materials Laboratory, Wright-Patterson Air Force Base, Ohio. The relationship of structural properties and the role of fracture mechanics in material selection are covered. The application of the selection criteria is demonstrated as it was applied to the Advanced Metallic Air Vehicle Structure.
1973-02-01
Technical Paper
730820
Thomas D. Whelpley
A unique laboratory system for evaluation of agricultural tractor engines and power trains has been developed which closely simulates field loading, operates on a continuous 24 h basis, and is fully automated to reduce manpower expense. The programming hardware in conjunction with a dynamometer system provides a continuous and efficient method of indoor evaluation which correlates well with results from field test units. A master load histogram produced from collected field data was used to derive an engine loading cycle. A data logging system monitors the test stands during unattended times. Certain shortcomings-lack of reaction to environmental conditions, geographical differences, an operator's “feel” of a vehicle-will not totally eliminate field testing.
1973-02-01
Technical Paper
730819
Robert E. Haight
A punched tape program is being used to control power shift transmission test stands operating as single or multiple units. Any desired shift sequence (sequence or skip shifting) is availabel with no concern for rate of shift lever movement, accuracy of detent postions, etc. Transmission shifting is accomplished by using electric solenoid valves to control the shift valves. Test unit design and construction, the test controller, test cycle design, test results, laboratory-field correlation, engine, costs, and test stand deficiences are covered. This system provides test flexibility, rapid data acquisition, engine life data, and minimum equipment investment.
1973-02-01
Technical Paper
730831
J. R. Griffin, H. L. Wittek
Laboratory development of modern diesel engine lubricants should ideally be done at the high output/speed conditions where the latest engines operate. In the late 1960's, the only engines available to the oil industry were the Caterpillar 1Y73 and the Petter AV-1. While useful test tools, neither of these engines can successfully operate at the desired conditions. Nor can they be successfully modified for that purpose. For these reasons, a joint project was established in 1969 between Chevron Research and List-Rosen-Wittek/AVL. Its purpose was to adapt one of the AVL diesel development engines to lubricant, emission, and fuel research. The design criteria developed included modern speed/output capability, durability, low maintenance, special lubrication features, adaptability, and balancing. These requirements resulted in a completely new design. A prototype was constructed, and this engine ran in October 1972. The design features are described and illustrated.
1973-02-01
Technical Paper
730817
James K. Dunn, Dan D. Lang
Complete power train assemblies are durability tested in the laboratory by applying real-time, field-recorded axle loads with an electrohydraulic servo system. Transmission shifting is servo-controlled, permitting testing with power shift and power shift-torque converter type transmissions. The load-control system permits selecting any duty cycle or combination of duty cycles for the laboratory loading. Computer analysis of field and laboratory load data gives a damage rate comparison and component life predictions. A general description of test objectives, equipment, and operation, as well as examples of test results and data comparisons, are given.
1973-02-01
Technical Paper
730818
Vernon G. Converse
Transmissions for off-road vehicles are tested functionally at the end of the production line under conditions which as nearly as possible simulate those of actual use. Pallets are used to obtain high utilization of the testing equipment. A check is made of such factors as regulator pressure, lube pressure, drag losses, gear noise, and torque under specific conditions. A description of the testing cycle, methods employed, and readings obtained is included.
1973-02-01
Technical Paper
730762
T. C. D. Manby, J. Matthews
The paper discusses historical development of the OECD test code for agricultural tractors, and describes the present form of tests and their implications. Centralized administration and technical supervision are provided by the scheme which attempts to reduce barriers to trade by avoidance of the need for duplication of testing. Possible future developments in the use of the code in relation to the European Common Market and other legislative authorities' requirements are mentioned.
1973-02-01
Technical Paper
730763
W. E. Splinter, G. W. Steinbruegge, D. E. Lane, L. F. Larsen
Procedures used at the Nebraska Tractor Test Laboratory in testing agricultural tractors are outlined. Tests conducted at other test laboratories are compared with Nebraska Tractor Test results. Tests are conducted to determine maximum horsepower at maximum power takeoff, maximum horsepower in operating gears, maximum pull available from the machine, and noise level at the operator station. These tests showed that a difference of roughly 6% resulted between the testing procedures, which could not be accounted for. It is hoped that this paper can contribute to the coordination of testing procedures at different testing stations, in an effort to improve the tests and to improve the tractor performance.
1973-02-01
Technical Paper
730713
J. W. Thompson
This paper describes the White Motor Corp. approach to heavy-duty diesel truck noise reduction. As part of the U.S. Department of Transportation Quiet Truck Program, a unique “free field” stationary vehicle noise test facility was designed and built for noise control development. The features of this facility and the techniques employed in vehicle noise source identification are presented.
1973-02-01
Technical Paper
730705
Donald L. Gibson
California has combined the best features of the random and periodic methods of vehicle inspection in a multipronged attack on the operation of unsafe vehicles. Specially trained personnel of the California Highway Patrol conduct vehicle inspections at random locations throughout the state, at fixed commercial vehicle inspection facilities, and at fleet owners' terminals to ensure compliance with statutory regulations. As a result of this balanced approach, the California motorist is provided with a quality vehicle inspection without economic hardship.
1973-02-01
Technical Paper
730987
P. E. Blatt
Advanced flight control concepts are expected to result in major design changes to the total vehicle configuration and to significantly improve the total mission effectiveness of near-future military aircraft. Fly-by-wire controls have been the catalyst that makes these advancements possible. Realistic appraisal of the current state-of-the-art in analog fly-by-wire controls and the major thrust to develop digital controls are presented.
1973-02-01
Technical Paper
730988
Thomas P. Peppler
This paper is a summary of the characteristics and development program for the U.S. Army heavy lift helicopter (HLH) fly-by-wire flight control system. The evolved control system consists of a triple channel direct electrical linkage which replaces the mechanical controls between the cockpit and the rotor control actuators and a triplex digital automatic flight control system. The direct electrical linkage has been successfully tested in a demonstration helicopter. The test helicopter utilized triple hydraulic driver actuators to control existing power actuators. In the HLH, the driver and power functions will be integrated into a single rotor control actuator consisting of a triple control stage and dual power stage. Transmission-driven dual hydraulic systems at each rotor head supply the two power stages and two of the control stages. A separate electrically driven hydraulic pump supplies the third section of the triplex control stage.
1973-02-01
Technical Paper
730957
H. E. Sutherland
The Advanced System Monitor (ASM) is an integrated display device using digital data acquisition and processing techniques, and is intended for a new generation of transport aircraft. It provides the flight crew with the critical airplane condition data in one centralized location. The equipment described constitutes the data acquisition, processing, and control portion which works in conjunction with the ASMs electronic display. The mechanization is a dual redundant system having operational modes which allow for the safe flight of aircraft even if there are two failures. The heart of the system is a general-purpose computer which monitors and, on command, provides the crew with aircraft condition status and automatically notifies of deteriorating conditions so that an appropriate action can be taken. This system also accommodates the recording of maintenance and crew performance parameters.
1973-02-01
Technical Paper
730953
John Donohue
There is a trend in future commercial aircraft toward more integration of systems, functions, and displays. Many benefits can be realized through proper integration, the most significant being improved operating efficiency. The Advanced Systems Monitor (ASM) is a display integration device using digital data acquisition and processing techniques together with a cathode ray tube or other advanced integrated displays. The ASM provides operating data to the flight crew and maintenance data to the ground crew. While these two functions appear different, the difference is quite often in form rather than substance. The system parametric data used for performance indication to the flight crew often have the intelligence to identify malfunctioning units to the ground crew. This intelligence can be extracted through use of the computer. Incorporation of a computer in the ASM design provides processed data to the crews, as well as raw data.
1973-02-01
Technical Paper
730412
Paul D. Clark, Darrold E. Roen
A system has been developed to load the power train of a lab test vehicle with field recorded torques. This loading is accomplished with hydraulically activated axle load brakes which are controlled by an electro-hydraulic servo system. The entire power train is then tested as though the tractor was operating in the field. The advantages of the test system include 24 h/day operation regardless of weather conditions and very consistent day to day loading of the test vehicle. This paper presents the reasons for starting the program and a description of the power train test system.
1973-02-01
Technical Paper
730385
J. A. Bert, L. J. Painter
This paper reports the results of an evaluation by the Coordinating Research Council (CRC) of a new test to measure the thermal stability of jet fuels. This new test, the jet fuel thermal oxidation test (JFTOT) by Alcor Inc., was designed to improve upon the ASTM-CRC Coker test. The Alcor JFTOT is described as to fuel system, the heater test tube section, the thermocouple calibration tube rating methods-both visual rating and light reflectance methods, test program format, effect of test time on deposit formation, the heater tube temperature profile, and visual and tube deposit rater ratings. The relationship between the ASTM-CRC Coker and the JFTOT is evaluated, and the precision of the JFTOT and various measurements are discussed.
1973-02-01
Technical Paper
730678
C. R. Forsman, W. R. Schwindeman
Modern electronic diagnostic equipment, which displays fuel injection pressure curves, combustion pressure patterns and compression quality, has been used to improve the reliability and repeatability of laboratory engine tests used for lubricant development and evaluation. Major savings in man hours per test engine and greater engine availability have been obtained, along with great improvement in test repeatability. The same equipment used in fleet maintenance has provided significant savings by detecting incipient breakdowns in time to make repairs and avoid engine replacement and on-the-road failures. The fleets tested showed 10-25% of the vehicles had specific malfunctions which could produce costly failures if not immediately repaired.
1973-02-01
Technical Paper
730667
R. S. Benson, P. C. Baruah
The results are presented of an extensive series of tests on a turbocharged 4-stroke diesel engine in which the test results are compared with predictions using a generalized computer program. An examination is made of the influence of the cylinder heat transfer coefficient, the cylinder wall temperature, the exhaust pipe wall temperature, and the air valve flow areas on the engine and turbocharger performance predictions in order to establish the limits of accuracy required for these data. The effect of including the intake system in the calculation is also examined. Results are presented comparing the actual performance of the turbocharger with the predicted performance using steady flow data.
1973-02-01
Technical Paper
730666
R. S. Benson, J. D. Ledger, N. D. Whitehouse, S. Walmsley
Comparison is made between the transient response of a medium-speed, turbocharged diesel engine subjected to sudden load changes on a test bed and the response of a computer simulation model of the engine. Brief details are given of the simulation techniques involved and the data required to set up the model. Despite close agreement of model and engine steady-state results over the whole normal operating range, the transient responses of the model were initially found to be much faster than the test-bed responses. It is shown that the most important factor causing this difference is the lack of knowledge of the combustion at low air-fuel ratios and hence prediction of engine exhaust temperature during transient operation. Good agreement was obtained when this was modified.
1973-02-01
Technical Paper
730650
Takeshi Inoh, Masaharu Aisaka
Tuning techniques for controlling three principal modes of elastic vibration-vertical, torsional, and lateral-in the frame/body structure of a heavy-duty truck are discussed. The components involved in the solution of the shake problem are the frame/cargo-body structure, the cab mounting, and the powerplant mounting. The method followed in this experiment was a three-dimensional mathematical model analysis using a transfer matrix. The theoretical estimates showed appreciable correlation with the experimental results obtained by using a electrohydraulic shaker system. This technique, based upon a study of the effects of various components on the three modes of shake, was applied to production trucks and produced quite favorable results.
1973-02-01
Technical Paper
730522
John C. Elston
A generalized approach is taken looking at automobile emissions and energy problems from the vantagepoint of a state government regulatory agency. The auto industry's vast capability for technology, mass production, quality control, and marketing ability culminates at the dealership. Thereafter, the vehicle is often viewed by the user much differently. Initially, this paper attempts to overlay many of the different disciplines that formulate the final product. By examining a wide range of environmental ills, in part created by the automobile, and by analyzing how the automotive industry has adapted to past crises, the impending emission and energy questions are explored by using various economic, regulatory, and engine design trend indicators. Prospectives for analyzing these problems are demonstrated.
1973-02-01
Technical Paper
730502
T. Sisson, R. Zimmerman, J. Martz
This paper describes methods of determining modal stiffness, inertia, and damping properties of automotive bodies and frames using transient testing techniques. The test equipment described is a digital Fourier analyzer system. The hardware and software used to obtain transfer functions of the vehicle components is discussed, and several examples are presented which compare frequency response data generated by the Fourier analyzer to the same data generated by the more standard sinusoidal excitation methods.
1973-02-01
Standard
AIR1208
ABSTRACT
1973-02-01
Standard
J140A_197302
This SAE Recommended Practice describes test procedures for evaluating hardware used in motor vehicle seat belt assemblies. Related hardware performance requirements are described in SAE J141. Test procedures and performance requirements for retractors will be covered in separate SAE Recommended Practices to be issued later.
1973-02-01
Technical Paper
730499
M. F. Dague, R. J. Montag, E. L. Haines
Product and materials evaluation testing has been revolutionized to meet the unique requirements of steel belted tires. Many of the classical cord and tire tests have been found to be inadequate and others to require modification. The development of many new test methods has been required. This paper discusses the tests used to characterize and evaluate steel for tires. These tests can be broadly divided into two categories: 1. Tests evaluating the steel cord material such as tensile properties and mechanical properties. 2. Tests evaluating the steel-rubber composite behavior such as adhesion and fatigue. Test parameters, data accumulation and treatment, and significance of test results are discussed.
1973-02-01
Technical Paper
730590
Norman S. Stahler, Fred Arndt
Under the Experimental Safety Vehicle (ESV) Program authorized by the National Traffic and Motor Vehicle Safety Act, AMF Inc. and Fairchild Industries developed the first ESVs under competitive contracts, while General Motors Corp. and Ford later developed ESVs under noncompetitive contracts. These contracts stated that ESV testing would be performed by an independent contractor. This paper describes the ESV test program through the GM phase of testing as related to methodology, operating procedures, and results, and the role of Dynamic Science Division of Ultrasystems Inc. as test contractor.
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