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Journal Article

ℒ1 Adaptive Flutter Suppression Control Strategy for Highly Flexible Structure

2013-09-17
2013-01-2263
The aim of this work is to apply an innovative adaptive ℒ1 techniques to control flutter phenomena affecting highly flexible wings and to evaluate the efficiency of this control algorithm and architecture by performing the following tasks: i) adaptation and analysis of an existing simplified nonlinear plunging/pitching 2D aeroelastic model accounting for structural nonlinearities and a quasi-steady aerodynamics capable of describing flutter and post-flutter limit cycle oscillations, ii) implement the ℒ1 adaptive control on the developed aeroelastic system to perform initial control testing and evaluate the sensitivity to system parameters, and iii) perform model validation and calibration by comparing the performance of the proposed control strategy with an adaptive back-stepping algorithm. The effectiveness and robustness of the ℒ1 adaptive control in flutter and post-flutter suppression is demonstrated.
Technical Paper

“Zero Defects”, Statistically Considered

2000-09-11
2000-01-2605
The requirement of “zero defects” is rapidly finding its way as a “standard” of quality in numerous quarters. This phrase has great psychological appeal, and is often taken literally at all levels in an organization even though quality motivation may be the intention. It is common to believe that when zero defects are found in the sample, this must be the case for “all the rest” as well. In this paper the technical side of “zero defects” is examined. We look at the statistics of zero defects and show what is implied about lot or process quality when zero defects is the actual sample outcome. The focus is on attribute measurements and includes some special cases where a significant measurement error exists and cases where a Bayesian statistical analysis may be appropriate.
Technical Paper

“Walking on Automotive Waste? - Plastic Recycling Opportunities for Waste Automotive Materials in the Footwear Industry Sector”

1998-02-23
981162
This paper demonstrates the possibilities of using Automotive waste plastic material from “end of life” vehicles (ELVs), in the Footwear Industry to manufacture shoe components. The study establishes the sustainability of the flow of ELVs, from the European Car Parc and identifies and estimates the quantity of plastic materials potentially available for recycling from ELVs. Four potential materials, Acrylonitrile/butadiene/styrene (ABS), Polypropylene (PP), Polypropylene/ethylene/propylene/diene (PP/EPDM) and Polyamide (PA), were identified and three materials (PP, PP/EPDM and ABS) were reprocessed from ELV components and evaluated by the Footwear Industry. As a result, ABS was recommended as an economically, suitable replacement for HIPS, the current material used for manufacturing shoe heel components.
Technical Paper

“Virtual Engine/Powertrain/Vehicle” Simulation Tool Solves Complex Interacting System Issues

2003-03-03
2003-01-0372
An integrated simulation tool has been developed, which is applicable to a wide range of design issues. A key feature introduced for the first time by this new tool is that it is truly a single code, with identical handling of engine, powertrain, vehicle, hydraulics, electrical, thermal and control elements. Further, it contains multiple levels of engine models, so that the user can select the appropriate level for the time scale of the problem (e.g. real-time operation). One possible example of such a combined simulation is the present study of engine block vibration in the mounts. The simulation involved a fully coupled model of performance, thermodynamics and combustion, with the dynamics of the cranktrain, engine block and the driveline. It demonstrated the effect of combustion irregularity on engine shaking in the mounts.
Technical Paper

“Understanding Diesel Engine Lubrication at Low Temperature”

1990-10-01
902177
Oil pumpability in passenger car gasoline engines was well-characterized by an ASTM program and by individual researchers in the 1970's and early 1980's. Oil pumpability in diesel engines however, was not investigated to any significant extent until the mid-1980's. This study was initiated to define the performance of several commercial viscosity modifiers in different formulations containing 3 detergent-inhibitor (DI) additive packages and 4 basestock types. The test oils were run at -18°C (0°F) in a Cummins NTC-400 diesel engine. The results, when statistically analyzed, indicated that a new, second generation olefin copolymer (OCP) viscosity modifier had better performance than a first generation OCP and, furthermore, had performance equal to a polymethacrylate (PMA) viscosity modifier. The analysis also showed that one DI/base stock combination had a significant effect on performance.
Technical Paper

“The Producers” New Row-Crop Tractors From John Deere

1982-02-01
821062
A line of five new row-crop tractors is being introduced by John Deere with innovative features including a 15-speed full power shift transmission, a high capacity, highly-maneuverable full-time mechanical front-wheel drive and micro-processor controlled instrumentation. In addition, the tractors have increased power, improved fuel economy, greater hydraulic power, improved hitch sensing, improved operator controls, lower sound levels, and revised styling. This paper documents the design and development of these new John Deere row-crop tractors.
Technical Paper

“The Influence of Idle, Drive Cycle and Accessories on the Fuel Economy of Urban Hybrid Electric Buses - Chassis Dynamometer Tests”

2003-11-10
2003-01-3438
Fuel economy can be part of a business case for a fleet making the decision to buy new HD hybrid drivetrain technologies. Chassis dynamometer tests using SAE Recommended Practice J2711 on a bus equipped with an Allison EP SYSTEM ™ hybrid system and operated on standard bus driving cycles have produced impressive gains of over 60%. Preliminary urban bus field tests, on the other hand, have shown lower fuel economy gains. The difference can be attributed, in part, to the use of accessories - most importantly air conditioning - which are parasitic loads on the vehicle. In this paper the characteristics of driving cycles are studied to determine those factors which have the strongest influence on fuel economy for hybrids. The data show that the number of stopping events in a route or cycle is a strong influence as is the average vehicle speed. Energy analysis will show the relationship of fuel economy benefit and battery energy within a driving cycle.
Technical Paper

“Test Methodology Development for Rig Level Validation of Light Weight Stabilizer Link of EV Bus Suspension”

2024-01-16
2024-26-0357
In the modern and fast growing automotive sector, reliability & durability are two terms of utmost importance along with weight & cost optimization. Therefore it is important to explore new technology which has less weight, low manufacturing cost and better strength. The new technology developed always seek for a quick, cost effective and reliable methodology for its design validation so that any modification can be made by identifying the failures. This paper presents the rig level test methodology to validate and to correlate the CAE derived strain levels, life cycle & failure mode of newly developed light weight stabilizer link for EV Bus suspension
Technical Paper

“Taguchi Customer Loss Function” Based Functional Requirements

2018-04-03
2018-01-0586
Understanding customer expectations is critical to satisfying customers. Holding customer clinics is one approach to set winning targets for the engineering functional measures to drive customer satisfaction. In these clinics, customers are asked to operate and interact with vehicle systems or subsystems such as doors, lift gates, shifters, and seat adjusters, and then rate their experience. From this customer evaluation data, engineers can create customer loss or preference functions. These functions let engineers set appropriate targets by balancing risks and benefits. Statistical methods such as cumulative customer loss function are regularly applied for such analyses. In this paper, a new approach based on the Taguchi method is proposed and developed. It is referred to as Taguchi Customer Loss Function (TCLF).
Technical Paper

“TFC/IW in 1982”

1982-02-01
820301
TFC/IW, total fuel consumption divided by inertia weight is reported with other engineering variables for recent EPA data for industry passenger cars and truck. TFC/IW is used in comparisons between gasoline and diesel engines, 49 States and California, passenger cars and trucks. The California fuel economy penalty due to more stringent emissions standards is discussed. The relationship between TFC/IW and ton miles per gallon is shown. Special attention is focused on 4 cylinder gasoline powered vehicles in 49 States passenger car fleet. The use of TFC/IW to answer the question, ‘What Changed?’ when comparing the fuel economies of two fleets is described.
Technical Paper

“Spacematic” Monitoring System

1998-09-15
982138
Pneumatic, manually operated, drilling machines are used to produce a significant proportion of all holes drilled during wing manufacture. Drilling machine design and the manual drilling process has not changed significantly in decades. By employing miniature, low power, electronics and interfacing techniques, a monitoring system has been developed. This system enables improved process control of the manual drilling operation. Machine calibration management, measurement of drill performance, jig drilling error control and asset management are some of the benefits attainable. This project will hopefully encourage others to discover the potential for improving historically established processes, by employing modern technological developments.
Technical Paper

“Smart sensing” of Oil Degradation and Oil Level Measurements in Gasoline Engines

2000-03-06
2000-01-1366
Proper lubrication of moving parts is a critical factor in internal combustion engine performance and longevity. Determination of ideal lubricant change intervals is a prerequisite to ensuring maximum engine efficiency and useful life. When oil change intervals are pushed too far, increased engine wear and even engine damage can result. On the other hand, premature oil changes are inconvenient, add to vehicle maintenance cost, and result in wasted natural resources. In order to determine the appropriate oil change interval, we have developed an oil condition sensor that measures the electrical properties of engine oil, and correlates these electrical properties to the physical and chemical properties of oil. This paper provides a brief background discussion of the oil degradation process, followed by a description of the sensor operational principles and the correlation of the sensor output with physical and chemical engine oil properties.
Technical Paper

“Seizure-Delay” Method for Determining the Seizure Protection of EP Lubricants

1939-01-01
390146
IT does not yet seem to be recognized fully that it is the local temperature at the surface of contact and not the local specific pressure that chiefly determines the occurrence of seizure under extreme-pressure-lubrication conditions. This local temperature is the result of the temperature level of the parts lubricated, considered as a whole (“bulk” temperature) and of a superimposed instantaneous temperature rise (temperature “flash”) which is localized in the surface of contact. It appears typical for extreme-pressure-lubrication conditions, as met in gear practice, that the temperature flash is much higher than the bulk temperature. With existing conventional test methods for the determination of the protection against seizure afforded by EP lubricants, a considerable rise of the bulk temperature mostly occurs; as it cannot be controlled sufficiently; thus, leaving an unknown margin for the temperature flash, it renders impossible a reliable determination.
Technical Paper

“Second-Generation” SAE 5W-30 Passenger Car Engine Oils

1986-10-01
861515
High performance lubricant additive systems have been developed to formulate SAE 5W-30 passenger car engine oils which meet current and anticipated requirements of the North American original equipment manufacturers. The trend in North America is to recommend SAE 5W-30 oils that not only meet the API SF requirements for gasoline engines (“first-generation” oils), but also meet the stringent API CC requirement for light duty diesel engines (“second-generation” oils). Furthermore, the engine builders have issued “world specifications” for motor oils which incorporate additional “second-generation” SAE 5W-30 characteristics, such as enhanced API SF limits, improved fuel efficiency, an increased margin of bearing protection, and lower finished-oil phosphorus levels. The additive systems described herein exceed API SF and CC requirements as well as “second-generation” performance hurdles.
Technical Paper

“STATE OF THE ART” REPORT ON WINTERIZATION OF CONSTRUCTION EQUIPMENT

1964-01-01
640064
As increasing populations set demands for the abundant natural resources of the colder regions, the complex industrial machines of American Industry are expected to build the new railroads, roads, cities, mines, power sources, airports and factories, and operate these activities year round. This paper reviews the basic problems of “winterization” and the design practices, materials and components used with varying effectiveness in “winterizing” construction and associated equipment for use in moderate and extreme cold geographical areas. Several new charts are included which offer design temperature data for the northern United States, Canada, Alaska, Greenland, as well as average January isotherms around the earth. The authors are members of CIMTC Subcommittee XV, “Environment”.
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