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An electrohydraulic or a hydromechanical system used in a mobile or industrial application is comprised of many different elements such as controllers, sensors, solenoids, pumps, valves, actuators etc. Often the characteristics of these components are non-linear and the interaction complex when subjected to various kinds of inputs and load situations. In order to design a stable and responsive hydraulic system application that would continue to perform reliably, it is essential to have a simulation model of the system at the early stage of the inception of the design. The simulation would predict the expected performance of each of the components of the system and be useful if the actual hardware deviates from the desired performance. To make the simulation effort expedient and worthwhile a faster computer and an easy to use software is necessary.

A major objective of many of today's corporations is reducing time to market for new products. This goal, coupled with the fact that systems are only becoming more complex is driving many engineering organizations to employ the use of virtual prototyping, simulation and control system design software. Unfortunately, despite the promise of these tools, no single dynamic system modeling package allows the engineer to easily prototype all aspects of a complex system; mechanisms, hydraulics, pneumatics, thermodynamics, powertrains and electric drives, digital controllers, state machines and electronics. One solution to this problem is to integrate multiple CAE applications, allowing the end-user to create and manipulate a complete virtual prototype of their entire system. This paper focuses on the work The Boeing Company has done integrating its dynamic system model, simulation, and control tool set, called EASY5®, with other CAE applications.

This paper explores the history behind the use of fine filters on off-road transmissions, the evolution of coreless filter technology, and the introduction of new coreless filters suitable for high temperature powershift transmissions.

As electronic systems for off-highway applications become increasingly complex, original equipment manufacturers (OEMs) must rely on outside suppliers to design the electronics and application software for these systems. Often, a combined development team is formed, with engineers from both the OEM and the supplier working together to design the system. While many methods for software process improvement exist, few of these methods deal directly with the unique challenges of coordinating and implementing software improvements for a geographically- and politically-split development team. The objective of this paper is to outline methods that may be used to create and develop a software process for such a split development team.

During the last few years, industry has come to face the demand of optimizing the ecological compatibility of its technical products. Especially the agricultural machinery branch is to develop ecologically compatible machines and facilities as these are used for work in ecologically sensitive areas. This paper will present the practical experiences of optimizing agricultural machines' ecological compatibility; it will also show a method designed for ecologically oriented agricultural machines' development in small and medium sized enterprises, based on these experiences.

Designers of mobile and off-highway equipment are developing more efficient systems to meet the demands of increased competition. Improving designs often includes a review of the hydraulic system, as engineers seek more efficient means of transmitting power. Increasingly, the focus is on reducing the size of hydraulic components or concentrating power in smaller package sizes. This can be accomplished by using higher operating pressures. To meet this challenge, developers of new off-highway hydraulic components must be able to test under those more demanding high pressure conditions. Fortunately, there are now more test-stand components available to support these manufacturers, as they design and qualify their products for higher operating pressures. Component testing is currently being conducted at pressures as high as 15 000 psi (1040 bar).

The operator of a sugarcane harvester cannot see the basecutter and depends on sound to adjust its height. A mechanical/hydraulic system was developed to follow the vertical changes in row height and the lateral changes in the location of sugarcane stalks on the top of the row. The system sensor was an articulated skid mounted in front of the cutter blade. Laboratory and field tests showed the system was able to keep the blade adjusted within 2.54 cm of the top of the row when tested under simulated field conditions.1

Electrorheological and magnetorheological fluids have found commercial application in a wide range of damping, force transmission and fluid flow arrangements, but are complex fluids, needing accurate rheological models for application design. In order to further the understanding of the behavior of these fluids under stress, a new lumped parameter (eight-element) model of shear-mode electrorheological fluid dampers has been developed. In this paper, the new model is presented and experimental data on damper force response is compared with model predictions over a range of sinusoidal input displacement amplitudes, input excitation frequencies and electric fields.

“Bio Fluids” have the remarkable property of rapidly degrading in natural environments. Unfortunately, the same fluid chemistry leading to biodegradation also leads to fluid instability in machine environments. This dilemma can be resolved through vigilant contamination control. Maintaining biodegradable fluids at extremely low levels of particulate contamination and extremely low levels of moisture discourages fluid deterioration, especially the breakdown mechanisms of oxidation and hydrolysis. Maintaining fluids clean and dry also achieves the additional benefits of limiting the wear and corrosion of mechanical components. The challenge is to control these contaminants in the fluid systems of heavy machinery operating in wet and dusty environments.

Despite the best preventative measures, ruptured hoses, spills and leaks do occur with the use of all hydraulic equipment. Although these releases do not usually produce an RCRA (Resource Conservation and Recovery Act) regulated waste, they are often reportable events. Clean-up and subsequent administrative procedures involve additional costs, labor, and work delays. Concerns about these releases, especially when they involve Sandia National Laboratories, New Mexico (SNL) vehicles hauling waste on public roads, prompted their Fleet Services Department (FS) to seek an alternative to conventional petroleum-based hydraulic fluids. Since 1996, SNL has participated in a pilot program, along with the University of Northern Iowa (UNI) Ag-Based Industrial Lubricants (ABIL) Research Program and selected vehicle manufacturers, to field test in twenty of its vehicles, hydraulic fluid produced from soybean oil.

The genetic modification of oilseeds has been a critical step in the evolution of biodegradable, non-toxic vegetable oil-based industrial fluids. Oils that are high in oleic acid possess the required properties for many industrial applications and have been successfully used as hydraulic fluids and numerous lubricants. Recently, the DuPont Co. has developed high oleic soybean varieties that produce oil with greatly improved oxidative stability. This oil provides the opportunity to make environmentally acceptable industrial fluids that may be lower in cost and/or functionally superior to vegetable oil-based fluids currently on the market. Research and testing over the last year has focused on utilizing genetically modified soyoil for industrial applications. Using standard bench tests and low volume fluid power pump tests, experiments were conducted to develop a soybean oil-based hydraulic fluid in cooperation with Lubrizol Corporation.

Traditionally, various testing methods are used to determine the lubrication properties of hydraulic fluids. The specific standard for mechanical testing of hydraulic fluids is based on a special type of hydraulic power unit, the vane pump (DIN 51 389, DIN 51 524). Numerous other procedures for mechanical testing of lubricants are used with the FZG-Test (DIN 51 354) being the most important one, in which the tested fluid is exposed to a certain load by shearing it in a gear set. Moreover industry uses several non-standard ‘in-house’ testing methods. This situation cannot be satisfying in many respects: Since only part of the interaction between fluid and component is tested with the existing test procedures, the validity of test results is limited. Reproducibility of the test results is also limited, especially in the case of the vane pump test, due to the number of necessary test procedures, cost and time expense is too high.

Measuring water quality and preventing drawbacks caused by deteriorated water quality in tap water fluid power systems is a unique problem. Tap water is a suitable environment for waterborne microorganisms. It also contains dissolved and undissolved organic and inorganic matter. Wear particles in the tap water fluid power systems are a separate problem, however closely linked to problems above mentioned. Contamination and the quality of the pressure medium in the system is a function of local characteristics of tap water, operating parameters, system and component design and contamination introduced to the system. To study effects of water quality on tap water fluid power systems, and to evaluate methods for measuring water quality and particle counting, a pilot scale hydraulic system was constructed. The pilot scale system emulates typical operation of a commercial tap water fluid power system.

Computer simulation of product usage is effective in achieving shorter product development time, integrating the efforts of suppliers, reducing test cost, providing early product direction and interfacing to CAD. However, simulation may not be appropriate when no objective metrics exist, the engineering phenomenon is not yet well understood, analysis technology does not exist to handle the specific problem or when knowledge based engineering is adequate. Simulation may be coupled to systems engineering to allow cascading engineering requirements for the entire product by specifying the systems that enable the achievement of customer wants and then cascaded to components that enable systems targets. Virtual Design of Experiments in the simulation process can provide major improvements in all phases of the product development process from concept screening to optimization to robustness.

Kubota has developed a lawn tractor series that will be produced in the USA with good cost to performance ratio and with new features for improved control and comfort. We believe this is the first in the industry of lawn tractor series that features the Cushion Ride system, Auto Throttle Advance system and other features. The new models, that were introduced this spring, were designed concurrently with a horizontal-axis water-cooled diesel engine and a vertical-axis water-cooled gasoline engine. Another new feature is the Electric Power Steering system. I will now discuss these newly introduced technologies.

The main purpose of this investigation was to develop the virtual prototype of the whole log forwarder by using ADAMS dynamic system simulation software. The virtual prototype contains hydraulic systems of the loader (except the grapple), mechanisms (steering, bogie axles), tire-terrain interaction, the log loader with structural flexibility and the control systems of the loader. Then the virtual prototype was validated with a simple procedure describing loading dynamics.

Washcoat sintering and substrate meltdown have traditionally been the principle deactivating mechanisms of catalysts fitted to two-stroke engines. The reduction of the excessively high HC and CO levels responsible for these effects has therefore been the focus of considerable research which has led to the introduction of direct in-cylinder fuel injection to some larger versions of this engine. However, much less attention has been paid to the effects of oil and its additives on the performance and durability of the two-stroke catalyst. The quantity of oil emitted to the exhaust system of the majority of two-stroke engines is much greater than in four-stroke engines of comparable output due to the total loss lubrication system employed. The fundamental design of the two-stroke also permits some of this oil to ‘short-circuit’ to the exhaust in a neat or unburned form.

The ASTM test method D-2882 (Standard Test Method for Indicating the Wear Characteristics of Petroleum and Non-Petroleum Hydraulic Fluids in a Constant Volume Vane Pump) is widely used to evaluate hydraulic fluids. Performing this method can be difficult due to problems with the pump hardware and the written procedure. This paper discusses the problems and suggests possible remedies.

A family of logic-based radio-controlled components, engine speed sensors, and industrial magnetic pulleys suitable for the most severe applications found in the environmental management industries has been developed. The relay logic boards are user friendly and user ready for an unlimited array of output to match OEM's ever-changing demand. The speed sensors relieve the engine power plant and drive components of unnecessary abuse when the plant is under a heavy load. The industrial magnetic head pulleys are a “new breed” of ceramic magnet that create a unique magnetic field capable of removing a large percentage of ferrite metal from waste wood grinding.

In the last two decades we have literally became a global society in all aspects of technology. Unfortunately, this has caused us to “race” to stay competetive and consistent in our desires to remain in this technological race. Any time an accelerated pace is demanded, mundane things are often overlooked. This becomes the basis for many lost opportunities.