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Operator fatigue and time-of-day induced variations in cognitive effectiveness can lead to lapses in attention, slowed reactions, and impaired reasoning and decision-making that has been shown to contribute to accidents, incidents and errors in a host of industrial and military settings. During the past three years, the US Air Force has sponsored the development of a model of human fatigue and circadian variation and a scheduling tool based upon the model that will be used to minimize aircrew fatigue. The initial test version of the tool has passed review by the operational wings of the AF and a final operational product is in advanced development and validation. The software was developed by SAIC and NTI and is called the Fatigue Avoidance Scheduling Tool (FAST™). This fatigue forecasting system is being developed and tested by NTI under a small business innovative research (SBIR) grant from the US Air Force, now in the third year of a three-year program.

SAE J1453 O-ring Face Seal (ORFS) Fittings have emerged as the premier fittings to eliminate fluid leakage. They utilize an elastomeric O-ring in a captive groove to prevent leakage at the fitting to tube/hose interface. A straight-sided groove had been used successfully for years, but it had the problem of not consistently retaining the O-ring in the groove until the fittings are assembled. A new dovetail groove, which positively retains the O-ring, has been designed and incorporated into the SAE J1453 standard. Several alternative designs were considered before agreeing to adopt the dovetail groove. This paper covers the development and testing conducted to adopt the dovetail groove in the SAE standard.

This paper reviews the development of an electrical diagnostic presentation adopted for John Deere products worldwide. Deere has adopted IEC 617 electrical symbols and incorporated them into a standard presentation format to simplify and improve the communication of electrical information to dealer technicians who service John Deere equipment. The diagnostic presentation is designed to provide the end user, the service technician, a common method for diagnosing electrical problems. It utilizes a combination of diagrams prepared by product engineering and service groups. Engineering is responsible 1) for developing a functional schematic diagram to explain the operation, function and interaction of the electrical devices, and 2) for developing a wiring diagram to show the harness flattened out with connectors and devices.

The purpose of this paper is to review the development of SAE J2244 by the SAE Fluid Conductors and Connector Technical Committee and to review the changes made to ISO 6149:1980 by the ISO Subcommittee to address the deficiencies which have prevented ISO 6149 from becoming “the International Port” for hydraulic fluid power applications. Because the needs of the global market-place have now been incorporated into SAE J2244 (ISO 6149), a basis will be established for making SAE J2244 (ISO 6149) the preferred port for the 90's, and thus: THE WORLD CLASS PORT & STUD ENDS FOR HIGH PRESSURE HYDRAULICS. SAE J2244 was developed in parallel with the revision of ISO 6149:1980 to provide U.S. users an industry standard for metric, straight thread ports and stud ends. SAE J2244 incorporates the extensive changes made to ISO 6149:1980 to complete its design. Heavy-duty and light-duty stud end dimensions, working pressures, burst pressures, and assembly torques have been developed.

Performance testing provides an important complement to urine testing as a determinant of fitness for duty. Performance testing can be conducted immediately to screen out impaired workers before they undertake safety related job functions. Urine testing involves the expense and delay of laboratory testing, and results relate more to life style than current on-the-job performance capability. This paper reviews performance based testing and discusses the development and application of two performance based screening devices. One device has the capability of rapidly screening for impaired psychomotor performance given previous baseline data. The second device provides the potential for screening psychomotor and divided attention performance without prior experience or baseline data.

A subjective assessment of ride quality was undertaken in order to estimate the relationships among 22 factors that affect concepts of ride quality and to assess the interaction of these factors with 7 ride quality issues. Nine line-haul drivers drove and rated each of 16 tractor-trailer vehicles. The factors, driver vibration, ease of steering, and interior cab noise determined overall impressions of ride quality. Of the issues, front axle load, tractor configuration, tractor rear suspension, trailer suspension, trailer load, wheel base length, and newer and older cab designs, the latter evoked the clearest differentiation of ride quality between paired vehicles.