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This four-hour short course intends to present an overview of electrohydraulic flow control servovalves commonly used in flight control and utility actuators. The scope of this course covers the history and design of servovalves, as well as their most common performance characteristics. This course will provide participants an understanding of the application of electrohydraulic servovalves in hydraulically powered actuators and preparation of the servovalve procurement specification.

This course is verified by Probitas Authentication as meeting the AS9104/3A requirements for continuing Professional Development. This four-hour short course will provide an overview of design considerations for electrohydrostatic actuation for transport and business aircraft applications.  The instructor will present the critical topics of electrohydrostatic actuation (EHA) from a systems development perspective (V-Approach).  Beginning with aircraft system requirements, the instructors will then guide participants through EHA subsystem requirements, component design, component verification test, aircraft integration, and use. 

This four-hour short course provides an introduction to contamination control principles in aircraft hydraulic systems. Topics covered include an introduction to the types of contamination in aircraft hydraulic systems, contaminant measurement, and reporting methods. In addition, the impact of contamination on hydraulic components is discussed in detail. Along with an introduction to filtration mechanisms, information on testing, rating, and specifying filters will be provided.

This four-hour short course provides an overview of hydraulic system design of typical business and commercial aircraft. Topics will include the principles, system architectures, power sources, and the main components and technologies of hydraulic systems including hydraulic power generation, filtration, fluid storage, distribution, sensing and control. The step by step process of designing a hydraulic system will also be reviewed. Additionally, future trends in hydraulic systems will be discussed.

This 4-hour short course provides an overview of Power Electronics (PE) in use in modern transport aircraft. This course includes the context, principles, design drivers, and the main PE components of various flight applications, including those for harsh environments. This course is designed to deliver and demystify the basic theories and best practices of mechanical, electronics, thermal management, safety, reliability and maintainability disciplines. In addition, future trends in Power Electronics will be discussed.

This 4-hour short course offers an overview of aircraft hydraulic pumps focusing on their application in hydraulic systems, design and performance characteristics, and integration issues. These topics will examine the various pump technologies available for aircraft system applications, their design, performance and operational characteristics and limitations, and discusses the challenges and lessons learned in the integration of pumps in hydraulic systems.

This half day course presents an overview of seals and sealing system design for military and commercial aircraft. It is aimed to provide engineers having some previous actuator and control valve design background with an understanding of the general hardware groove standards, standard parts for static applications and how seal designs and sealing systems can be best used in dynamic reciprocating and rotary applications. Information will be provided regarding seal material and fluid compatibility, friction drag, expected wear rates depending on operating conditions and duty cycle, hardware surface finish and topography.

This four-hour short course intends to present an overview of electrically powered flight control actuation systems, covering commercial applications. The scope covers issues related to the mechanical design of actuators themselves, with limited reference to their control electronics. Additionally, this course will provide participants an understanding of the design considerations behind these actuation systems.

This four-hour short course provides an introduction to fluids for aerospace hydraulic systems. Topics covered include an introduction to basics fluid properties, rheology, tribology, and fluid product development. In addition, the history and performance of different classes of fluids are discussed in detail, and specific failure modes such as erosion and sludge formation will be described. Along with an introduction to fluid degradation, information on used oil analysis test methods and interpretation will be provided.

This four-hour short course provides key considerations for the comparison of electrically supplied (Power-by-Wire, or PbW) and hydraulically supplied (Power-by-Pipe, of PbP) actuation for aerospace. The focus is put on the consequence, for designers, of changing the physical principles and the technology used. A particular attention is paid to the unavoidable side effects introduced by the technological realization. Simple examples with realistic numerical values are used to make the comparisons quantitatively realistic.

This technical paper collection contains 49 papers detailing military vehicle technology. Topics covered include: reliability growth for military vehicles, upgrading readiness, rapidly installed fluid transfer system, robotic technologies, electrical systems modeling and simulation, nanofluid research, and more.

Abstract The mechanical efficiency of the current continuously variable transmission (CVT) suffers from high pump loss induced by a high-pressure system. A novel wedge mechanism is designed into the CVT clamp actuation system to generate the majority of clamp force mechanically. Therefore, the hydraulic system can operate at a low-pressure level most of the time, and the pump loss is greatly reduced to improve the CVT’s mechanical efficiency. Through dynamic analysis and design optimization, 90% of clamp force is contributed by the wedge mechanism and the rest of the 10% is generated by a conventional hydraulic system. The optimal design is validated through dynamic modeling using Siemens Virtual.Lab software by simulating the wedge clamp force generation, ratio change dynamics, and system response under tip-in conditions. After that, we built prototype components that target 70% of the clamp force contributed by the wedge mechanism and tested them on a transmission dynamometer.

Abstract In this article, compared with traditional Remote Parameter Control (RPC), the iterative process is improved based on linear transfer function (TF) estimation of the nonlinear dynamic system. In the improved RPC, the iteration coefficient is designed according to the convergence condition of the nonlinear iterative process, so that the convergence level, convergence speed, and iteration stability could be improved. The difference between the traditional and the improved RPC iterative process is discussed, the RPC iterative process of the nonlinear system is analyzed, and channel decoupling for Multi-Input Multi-Output (MIMO) system based on eigen-decomposition of the system TF and linear TF estimation is introduced. It assumes that the eigenvector matrix of the system TF remains the same, and the linear TF in the iterative process is estimated and updated, which is used for iterative calculation.

Abstract Inline piston pumps are extensively used in aircraft hydraulic systems. They can be found in engine-driven large-sized hydraulic pumps and zonal electric motor-driven mid-small sized pumps. Inline piston pumps are positive displacement pumps with variable volumetric flow controls. Positive displacement pumps can provide a variable flow rate over a wide range of suction pressures. Aircraft fly at high altitudes, and therefore these pumps have to work in extreme conditions such as low atmospheric pressure, low temperature. At low inlet pressures, the pump is highly susceptible to cavitation, i.e., insufficient filling capacity. The pressure below which pump flow rate drops drastically is known as critical inlet pressure. Extensive research has been carried out to study cavitation in inline piston pumps.