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A laboratory axle efficiency test using a torque sweep method has been developed. Vehicle test limitations, previous axle efficiency tests and origin of current test are discussed. Test development, equipment and importance of technique are presented. Correlation with vehicle tests is shown and usefulness of data for evaluating lubricant and axle design changes is discussed. An evaluation of test results shows that the torque sweep method has the capability of identifying changes that may not show with vehicle tests.

The question of the use of tires and tracks on agricultural prime movers is again surfacing. The four-wheel drive market is growing fast, particularly in areas where crawlers have been popular. The relative performance characteristics of tires and tracks are compared in agricultural soil conditions. Performance analysis shows that a four-wheel drive tractor should have a 22 percent higher productivity than a similar weighted track layer in a firm soil. This is due to the higher axle power of the four-wheel drive tractor. A track layer should outproduce a four-wheel drive of equal axle power (with proper weight-to-power) by 12 percent. A four-wheel drive tractor had a 36-50 percent higher productivity than a similar weighted track layer in sugarcane conditions for several tillage operations. For similar weighted tractors, owning and operating costs per hectare for a four-wheel drive tractor were 33 percent less than that for a track layer. No significant differences in soil compaction between crawler and four-wheel drive tractors were found in field experiments. There was no significant compaction below the tillage zone for both tractors. Theoretical predictions agreed well with field experiments.

The objectives of the Applications Technology Satellite (ATS) Program are to advance space technology in areas of importance to mankind. A brief description of the planned satellites and experiments is presented. The experiments include instructional television, communications, navigation, meteorology, spacecraft technology and science. The ATS-F and -G satellites will have 30-foot deployable antennas and will serve as three-axis stabilized platforms in geostationary orbit with 0.1 degree pointing accuracy.

The health of inflatable structures, including space suits and habitats, is dependent upon the integrity of the gas retention structural layer. Inflatable structures typically utilize a coated fabric gas retention layer, or bladder. Threats such as Micrometeoroid and Orbital Debris (MMOD) penetration and inadvertent impact with sharp objects can cause a breach of the gas retention layer. Leakage as a result of bladder breach will impact operations due to loss of consumables and time spent locating and repairing the defect. Crew safety can be at risk where high rate leakage could cause loss of mission or loss of life. ILC has recently researched self-healing technologies that prevent leakage by closing penetrations of the gas retention structure and that are viable and scalable for various future missions and applications ranging from the Constellation Space Suit System (CSSS) to deployable lunar habitats. Several candidates of passive self-healing systems were studied. System impacts such as the size of the hole that can be healed, material mass and thickness, and system inflation pressure were considered. Candidates were evaluated based on derived requirements for a flexible inflatable system. In 2001 a Shuttle Space Suit Assembly (SSA) lower arm component prototype with a viscoelastic gel self-healing bladder was fabricated and puncture tested in vacuum. The performance of this viscoelastic gel solution was used for comparison with new concepts that have recently been developed and tested.

A new 40-channel CB radio system had been developed by a major automotive manufacturer as a regular production option for a number of its 1978 cars and trucks. To maximize theft resistance, the system uses a remote chassis, detachable microphone, and a tri-band antenna. This state-of-the-art system is presented here in terms of component functions, design development, manufacture, and test equipment and procedures.

Essais des huiles de moteurs reduisant la consommation de carburant. Description de l'essai dynamometrique sequence VI de l'ASTM (American society for testing and materials)

KE-Jetronic (Kontinuierlich electronic): un nouveau systeme d'injection continue multipoint a commande electronique avec fonctionnement mecanique en cas d'avarie

The function of the system valve stem - valve guide is dependent on the material combination and the available amount of oil. The wear on both components must be low at high running times to ensure a save function and keep the emission of the engine low. The knowledge about the friction- and wear mechanism is not obviously caused by missing information about the real amount of oil in the guide and over the oil transportation. This paper describes, in which way it is possible to visualize the valve behavior in a valve guide. Two test rigs with valve guides made out of glass are built up to investigate the behavior of the valve under running conditions. This research work realized for the first time, taking photographs of the oil distribution in a original scaled valve guide under running conditions. The following could be visualized: • The oil film and the oil pressure distribution between valve stem and valve guide with different clearances had been investigated. A closed hydrodynamic oil film only can built up in a capillary gap. • At a great valve clearance no sufficient oil film pressure could build up. Increasing the oil content does not solve this problem. By missing oil film pressure wear is visible immediately. • The amount of oil transported towards the valve head - represents a part of the oil consumption in a real engine with a negative influence for the emissions- increased excessively with the valve stem clearance. • The influence of worn out valve stem sealing is more severe, the greater the valve clearance is. • The very complex secondary movement of the valve in the guide is strongly dependent on the amount of oil. In this paper fundamental knowledge for understanding the system valve stem - valve guide are described.

The oxidation stability of automatic transmission fluids can be evaluated using several approaches. These include motored transmission oxidation tests. The Aluminum Beaker Oxidation Test is one of the tests specified for MERCON tm service ATF. This paper provides a summary of the test procedure, reviews the data supporting the validity of the test, and presents information on the repeatability and reproductibility of the test method

The authors would like to acknowledge the “Competitive Research Grants (CRG) Program”, King Abdullah University of Science and Technology (KAUST) for directly funding this research. The authors also appreciate all of the assistance provided by the KAUST engine laboratory staffs in the support of this investigations.

This work was supported by King Abdullah University of Science and Technology (KAUST) Office of Sponsored Research under the award number OSR-2019-CRG7-4077, and the KAUST Clean Fuels Consortium (KCFC) and its member companies.