Search Results

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.

课程概述 Powertrain controls for NEVs are one of the most complex and highly confidential areas of NEV research and development.  This two-day course takes the seemingly complicated field of NEV powertrain controls and summarizes it into a few basic principles.  The latest and most popular NEV powertrains are also reviewed to illustrate these principles and the controls strategies used.  对于新能源汽车来说，动力总成控制一直以来都是最复杂的和高度机密的领域之一。在这两天的课程中，我们将把看似复杂的动力总成控制系统总结出几条基本规则，同时，通过对当今其他车型动力控制系统的案例分析，来把这些规则和原理进行融会贯通。

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.

The purpose of this four hour short course is to provide information to understand how is established the basic architecture of a Flight Control Actuation System of a transport airplane, i.e. understanding the rationale for the distribution of the control surfaces, power sources, actuators and computers.

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 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 four-hour short course will present an overview of hydraulically powered flight control actuation systems used on fly-by-wire aircraft, covering both military and commercial applications. The scope this course covers the issues related to the mechanical design of actuators themselves, as well as their control electronics. Additionally, this course will provide participants an overview of the design considerations behind these flight control actuation systems.

This 4-week virtual-only experience is conducted by leading experts in the autonomous vehicle industry and academia. You’ll develop an understanding of the fundamentals of AV architecture, including mechatronics, kinematics, and the sense-think-act framework in autonomous systems. The course builds a connection for how robotics are used in autonomous vehicles and provides you with demonstrations, procedures, and the skills necessary to program a robot with basic commands using the Robot Operating System (ROS).

The difficulty in locating crash sites has prompted international efforts for alternatives to quickly recover flight data. This document describes the technical requirements and architectural options for the Timely Recovery of Flight Data (TRFD) in commercial aircraft. ICAO and individual Civil Aviation Authorities (CAAs) levy these requirements. The ICAO Standards and Recommended Practices (SARPs) and CAA regulations cover both aircraft-level and on-ground systems. This report also documents additional system-level requirements derived from the evaluation of ICAO, CAA, and relevant industry documents and potential TRFD system architectures. It describes two TRFD architectures in the context of a common architectural framework and identifies requirements. This report also discusses implementation recommendations from an airplane-level perspective.

The presentation describes technology developments and the integration of these technologies into new emission control systems. As in other years, the reader will find a wide range of topics from various parts of the world. This is reflective of the worldwide scope and effort to reduce diesel exhaust emissions. Topics include the integration of various diesel particulate matter (PM) and Nitrogen Oxide (NOx) technologies as well as sensors and other emissions related developments. Presenter Atsuo Kondo, NGK Insulators, Ltd.

Simulation-based tolerance analysis is the accepted standard for dimensional engineering in aerospace today. Sophisticated 3D model-based tolerance analysis processes enable engineers to measure variation in complex, often large, assembled products quickly and accurately. Best-in-class manufacturers have adopted Quality Intelligence Management tools for collecting and consolidating this measurement data. Their goal is to completely understand dimensional fit characteristics and quality status before commencing the build process. This results in shorter launch cycles, improved process capabilities, reduced scrap and less production downtime. This paper describes how to use simulation-based approaches to correlate the theoretical tolerance analysis results produced during engineering simulations to actual as-built results. This allows engineers to validate or adjust as-designed simulation parameters to more closely align to production process capabilities.

With the growing use of carbon fiber composite structure in Aircraft Manufacturing, the challenge of drilling carbon fiber stacked with Titanium has become a focus point. Due to the abrasive nature of the carbon fiber (CF), cutting tool life is relatively short when drilling carbon fiber stalked with Titanium. A common drill wear indicator is exit burr formation in the Titanium. As drilling tools wear due to the abrasive nature of the CF, the exit burr in the in the Titanium increases. This study seeks to understand the factors that lead to tool wear and exit burr formation. A correlation may be made relating drilling thrust forces with exit burr formation. Different cutting tools geometries and materials are studied using a high speed camera to attempt to understand the factors influencing exit burr formation. Findings are optimized and tested. Decreasing exit burr in the drilling of CF and Titanium may increase tool life thereby reducing tool costs to airframe manufacturers.

Impact of driving patterns on fuel economy is significant in hybrid electric vehicles (HEVs). Driving patterns affect propulsion and braking power requirement of vehicles, and they play an essential role in HEV design and control optimization. Driving pattern conscious adaptive strategy can lead to further fuel economy improvement under real-world driving. This paper proposes a real-time driving pattern recognition algorithm for supervisory control under real-world conditions. The proposed algorithm uses reference real-world driving patterns parameterized from a set of representative driving cycles. The reference cycle set consists of five synthetic representative cycles following the real-world driving distance distribution in the US Midwestern region. Then, statistical approaches are used to develop pattern recognition algorithm. Driving patterns are characterized with four parameters evaluated from the driving cycle velocity profiles.

Four-way, integrated, diesel emission control systems that combine selective catalytic reduction for NOx control with a continuously regenerating trap to remove diesel particulate matter were evaluated under real-world, on-road conditions. Tests were conducted using a semi-tractor with an emissions year 2000, 6-cylinder, 12 L, Volvo engine rated at 287 kW at 1800 rpm and 1964 N-m. The emission control system was certified for retrofit application on-highway trucks, model years 1994 through 2002, with 4-stroke, 186-373 kW (250-500 hp) heavy-duty diesel engines without exhaust gas recirculation. The evaluations were unique because the mobile laboratory platform enabled evaluation under real-world exhaust plume dilution conditions as opposed to laboratory dilution conditions. Real-time plume measurements for NOx, particle number concentration and size distribution were made and emission control performance was evaluated on-road.

This document establishes the minimum criteria for effective training of air carrier and contractor personnel to deice/anti-ice aircraft to ensure the safe operation of aircraft during ground icing conditions. Appendix D specifies guidelines for particular airplane models.

Abstract This article presents a comprehensive investigation for the interaction between vehicle ride vibration control and braking control using two degrees of freedom (2DOF) quarter vehicle model. A typical limited bandwidth active suspension system with nonlinear spring and damping characteristics of practical hydraulic and pneumatic components is controlled to regulate both suspension and tire forces and therefore provide the optimum ride comfort and braking performance of an anti-lock brake system (ABS). In order to design a suitable controller for this nonlinear integrated system, various control techniques are followed including state feedback tuned using Linear Quadratic Regulator (LQR), state feedback tuned using Genetic Algorithm (GA), Proportional Integrated (PI) tuned genetically, and Fuzzy Logic Control (FLC). The ABS control system is designed to limit skid ratio below threshold of 15%.

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 Path tracking is an essential stage for vehicle safety control. It is more newsworthy than ever in the automotive context and especially for autonomous vehicle. The study proposes an optimal control method for path tracking problem in inverse vehicle handling dynamics. The proposed method generates an expected trajectory which guarantees minimum clearance to the prescribed path by identifying the optimal steering torque input. Based on this purpose, the path tracking problem, which is treated as an optimal control problem, is then solved by local collocation method and mesh refinement. Finally, a real vehicle test is executed to verify the rationality of the proposed model and methodology. The results show that using control variables as a mesh refinement function can capture the dramatic changes in state variables, and the efficiency improvement is more significant as the number of the grid points increases.

Abstract It is reasonable to use a two-phase heat transfer loop (TPL) in a thermal control system (TCS) of spacecraft with large heat dissipation. One of the key elements of TPL is a heat-controlled accumulator (HCA). The HCA represents a volume which is filled with vapor and liquid of a single working fluid without bellows. The pressure in a HCA is controlled by the heater. The heat and mass transfer processes in the HCA can proceed with a significant nonequilibrium. This has implications on the regulation of TPL. This article presents a mathematical model of nonequilibrium heat and mass transfer processes in an HCA for microgravity conditions. The model uses the equations of mass and energy conservation separately for the vapor and liquid phases. Interfacial heat and mass transfer is also taken into account. It proposes to use the convective component k for the level of nonequilibrium evaluation.

Abstract Commercial vehicles contribute to the majority of freight transportation in the United States. They are also significant fuel consumers, with over 23% of fuel used in transportation in the United States. The gas price volatility and increasingly stringent regulation on greenhouse-gas emissions have driven manufacturers to adopt new fuel-efficient technologies. Among others, an advanced transmission control strategy, which can provide tangible improvement with low incremental cost. In the commercial sector, individual drivers have little or no interest in vehicle fuel economy, contrary to fleet owners. Aggressive driving behavior can greatly increase the real-world vehicle fuel consumption. However, the effectiveness of transmission calibration to match the shift strategy to the driving characteristics is still a challenge.