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2016-09-20
Technical Paper
2016-01-2005
Jia Zeng, Zhenjie Shu, Shan Zhu
Interest in civil unmanned aircraft system (UAS) is growing worldwide, as it has the potential to create new applications and markets in civil domains. As the related technologies, including micro-electronics, composite structure, autonomous control, green energy, has been seen a rapid development, various types of UAS are constantly emerging following the expansion of functions and applications. Thus, there is a need for classified management supervision and certification for UAS. Considering the lacking of standardization for UAV category and classification, it is extremely urgent to raise a proper standard to classify and categorize UAS.
2016-09-20
Technical Paper
2016-01-1994
Wei Wu, Yeong-Ren Lin, Louis Chow, Edmund Gyasi, John P. Kizito, Quinn Leland
Abstract For aircraft electromechanical actuator (EMA) cooling applications using forced air produced by axial fans, the main objective in fan design is to generate high static pressure head, high volumetric flow rate, and high efficiency over a wide operating range of rotational speed (1x∼3x) and ambient pressure (0.2∼1 atm). In this paper, a fan design based on a fan diameter of 86 mm, fan depth (thickness) of 25.4 mm, and hub diameter of 48 mm is presented. The blade setting angle and the chord lengths at the leading and trailing edges are varied in their suitable ranges to determine the optimal blade profiles. The fan static pressure head, volumetric flow rate, and flow velocity are calculated at various ambient pressures and rotational speeds. The optimal blade design in terms of maximum total-to-total pressure ratio and efficiency at the design point is obtained via CFD simulation.
2016-09-20
Journal Article
2016-01-2030
Jon Zumberge, Michael Boyd, Raul Ordonez
Cost and performance requirements are driving military and commercial systems to become highly integrated, optimized systems which require more sophisticated, highly complex controls. To realize benefits of those complex controls and make confident decisions, the validation of both plant and control models becomes critical. To quickly develop controls for these systems, it is beneficial to develop plant models and determine the uncertainty of those models to predict performance and stability of the control algorithms. A process of model and control algorithm validation for a dc-dc boost converter circuit based on acceptance sampling is presented here. The validation process described in this paper is based on MIL-STD 3022 with emphasis on requirements settings and the testing process. The key contribution of this paper is the process for model and control algorithm validation, specifically a method for decomposing the problem into model and control algorithm validation stages.
2016-09-20
Technical Paper
2016-01-2058
Thibaut Billard, Cedric Abadie, Bouazza Taghia
Abstract The present paper reports non-electrically intrusive partial discharge investigations on an aeronautic motor. Relevancy, robustness and repeatability of partial discharge testing procedures, both on insulating materials characterization and on operating aeronautic equipment are essential to ensure reliability of the aircraft systems. The aim of this paper is to be the very first step of defining such procedures and the associated test equipment. To do so, the paper will start by providing an understanding of partial discharge phenomena and will review typical more electrical aircraft architecture. Key characteristics causing partial discharge risk to increase will be highlighted. The impact of harness length, high performance power electronics and voltage level increase on insulation system is demonstrated.
2016-09-20
Journal Article
2016-01-2051
Andreas Himmler, Lars Stockmann, Dominik Holler
Abstract The application of a communication infrastructure for hybrid test systems is currently a topic in the aerospace industry, as also in other industries. One main reason is flexibility. Future laboratory tests means (LTMs) need to be easier to exchange and reuse than they are today. They may originate from different suppliers and parts of them may need to fulfill special requirements and thus be based on dedicated technologies. The desired exchangeability needs to be achieved although suppliers employ different technologies with regard to specific needs. To achieve interoperability, a standardized transport mechanism between test systems is required. Designing such a mechanism poses a challenge as there are several different types of data that have to be exchanged. Simulation data is a prominent example. It has to be handled differently than control data, for example. No one technique or technology fits perfectly for all types of data.
2016-09-20
Technical Paper
2016-01-2064
Shashank Krishnamurthy, Stephen Savulak, Yang Wang
Abstract The emergence of wide band gap devices has pushed the boundaries of power converter operations and high power density applications. The wide band gap devices in conjunction with silicon on insulator electronic components enable the realization of power converters that can operate at high ambient temperatures that are typically found in aerospace engine environments. This paper describes the design and test of a power electronic inverter that converts a fixed input DC voltage to a variable voltage variable frequency three phase output. The design of the key functional components such as the gate drive, power module, controller and communication will be discussed in this paper. Test results for the inverter at high temperature are also presented.
2016-09-20
Technical Paper
2016-01-2044
Jeffrey J. Joyce, Scott Beecher, Laurent Fabre, Ramesh Rajagopalan
Over the past few decades, advanced methods have been developed for the analysis of digital systems using mathematical reasoning, i.e., formal logic. These methods are supported by sophisticated software tools that can be used to perform analysis far beyond what is practically achievable using “paper and pencil” analysis. In 2011, RTCA published RTCA DO 178C along with a set of supplements including RTCA DO 333 which provides guidance on the use of formal methods towards the certification of airborne software. Such methods have the potential to reduce the cost of verification by using formal analysis instead of conventional test-based methods to produce a portion of the verification evidence required for certification. Formal methods can also be used to find problems earlier in the development process – for example, while the requirements are being developed rather than during system integration when the cost of re-working the requirements and design is much higher.
2016-09-20
Technical Paper
2016-01-2039
Prashant S. Vadgaonkar, Ullas Janardhan
Avionics industry is moving towards fly-by wire aircrafts with less reliance on mechanical systems leading to increase in the complexity of in-flight hardware elements. RTCA/DO-254 and EUROCAE ED-80 plays a vital role in the design assurance of airborne electronic hardware. RTCA/ DO-254 and EUROCAE ED-80 are the industry standards for Design Assurance Guidance for Airborne Electronic Hardware. The two different agencies FAA and EU regulate and apply this design assurance guidance to the regulatory law in CFR and EASA CS respectively. This paper discusses the need for DO-254 /ED-80 certification in Aerospace industry, the advantages and benefits to the avionics manufacturers. The paper presents the study made on similarities and differences between DO-254/ED-80.
2016-09-20
Technical Paper
2016-01-2000
Mark Bodie, Thierry Pamphile, Jon Zumberge, Thomas Baudendistel, Michael Boyd
Abstract As technology for both military and civilian aviation systems mature into a new era, techniques to test and evaluate these systems have become of great interest. To achieve a general understanding as well as save time and cost, the use of computer modeling and simulation for component, subsystem or integrated system testing has become a central part of technology development programs. However, the evolving complexity of the systems being modeled leads to a tremendous increase in the complexity of the developed models. To gain confidence in these models there is a need to evaluate the risk in using those models for decision making. Statistical model validation techniques are used to assess the risk of using a given model in decision making exercises. In this paper, we formulate a transient model validation challenge problem for an air cycle machine (ACM) and present a hardware test bench used to generate experimental data relevant to the model.
2016-09-18
Technical Paper
2016-01-1913
Alessandro Sanguineti, Federico Tosi, Andrea Bonfanti, Flavio Rampinelli
Organic brake pads for automotive can be defined as brake linings where the bonding matrix is constituted of high-temperature thermosetting resins. Bonded together inside the polymeric binder are a mix of components (e.g. abrasives, lubricants, reinforcements, fillers, modifiers…), each playing a distinctive role in determining the tribology and friction activity of the final friction material. The herein reported work presents novel inorganic “alkali-activated”-based materials suitable for the production of alternative brake linings (i.e. brake pads), by means of an unconventional low-temperature wet process. Exploiting the hydraulic activity of specific components when exposed to an alkaline environment, such peculiar inorganic materials are capable of coming to a complete hardening without the need of traditional high-temperature energivorous procedures.
2016-09-18
Technical Paper
2016-01-1918
Yusuke Aoki, Yasuyuki Kanehira, Yukio Nishizawa
Brake squeal is an uncomfortable noise that occurs while braking. So, it is an important issue for automobile quality to prevent brake products from squealing. Brake shims are widely used to reduce squeal occurrence rate. To quantify the anti-squeal effect of shims, loss factor has been measured with a bending mode tester, instead of repeating many dynamometer tests. However, there are cases where measurement results have less correlation to actual squeal suppression rate. Therefore, we have to evaluate the anti-squeal effect by dynamometer or on an actual car until the best shim can be selected. In this work, we focused on the differences between measurement conditions and actual braking conditions of shims to obtain a good correlation. The bending mode tester measures loss factor under pressure-free condition even though shims are compressed by pistons or cylinders towards the backplate of the pad.
2016-09-18
Technical Paper
2016-01-1932
Niclas Strömberg
During several years a toolbox for performing virtual rig tests of a brake disc has been developed by the author. A thermo-flexible multi-body model of a test rig is derived and implemented. A thermo-mechanical model of the pad-disc system is formulated including thermo-elasticity, frictional contact and wear. The energy balance at the contact interface is governed by contact conductance that depends linearly on the contact pressure and the frictional heat depends on a temperature dependent coefficient of friction. Instead of adopting a standard Lagrangian approach, the disc is formulated in an Eulerian frame like a fluid. This is then coupled to the pad most accurately by using Signorini’s contact conditions, Coulomb’s law of friction and Archard’s law of wear. The numerical treatment of these laws are performed by applying an augmented Lagrangian formulation, which in turn is solved with a non-smooth Newton method.
2016-09-18
Technical Paper
2016-01-1953
Michael Herbert Putz, Harald Seifert, Maximilian Zach, Jure Peternel
Vienna Engineering (VE) is working since more than eight years on an electro-mechanical brake (EMB) with a special eccentric and highly non-linear actuation mechanism. The principle allows e.g. high brake torque in approx. 50 milliseconds with only approx. 3 A rms actuator current at 12 V. This EMB reached an elaborated state and versions for passenger cars, elevators, railway and commercial vehicles (CVs) were derived. Now, as the EMB is going to road tests, it is necessary to closely fulfill safety requirements. What these safety requirements are and how they can be fulfilled is discussed in this paper: That are properties of the overall system and of the mechanics and electronics of the single brake. The overall brake system for EMBs needs a truly redundant power supply, a safe control bus and a safe brake pedal. The mechanics of a single brake can be required to release when power is off and it must not get mechanically stuck.
2016-09-18
Technical Paper
2016-01-1915
Meechai Sriwiboon, Seong Rhee, Kritsana Kaewlob, Nipon Tiempan, Rungrod Samankitesakul
Two formulations have been selected and tested for this investigation; Low-Copper NAO and Copper – Free NAO. Each formulation was processed to achieve 3 levels of porosity; 12, 17 and 22%. Each sample was tested for hardness (HRR, HRS, and HRL), natural frequencies and compressibility plus performance testing for friction, wear and brake squeal. This paper describes correlations or lack of them between all the measurements.
2016-09-18
Technical Paper
2016-01-1920
Deaglan O'Meachair, Stamatis Angelinas, Matthew Crumpton, Antonio Rubio Flores, Juan Garcia, Pablo Barles
Bentley Motors Ltd. has developed a Carbon Silicon Carbide (CSiC) brake system for it’s Mulsanne product, introduced at 17MY. The CSiC brake system is conceived as a performance brake system, and as such offers notable improvements in brake performance In developing the brake system, particular focus was placed on meeting the refinement levels required for a premium product, and indeed as the flagship model for Bentley Motors, NVH refinement of the brake system was of particular concern. This paper intends to discuss the technical performance of the brake system and review the NVH performance of the brakes. This paper will also demonstrate the effect of vehicle isolation on the cabin NVH, and ultimately the passenger experience, by comparing the noise and vibration content in the wheel arch with that apparent to the driver.
2016-09-18
Journal Article
2016-01-1925
David B. Antanaitis
Abstract The strong focus on reducing brake drag, driven by a historic ramp-up in global fuel economy and carbon emissions standards, has led to renewed research on brake caliper drag behaviors and how to measure them. However, with the increased knowledge of the range of drag behaviors that a caliper can exhibit comes a particularly vexing problem - how should this complex range of behaviors be represented in the overall road load of the vehicle? What conditions are encountered during coastdown and fuel economy testing, and how should brake drag be measured and represented in these conditions? With the Environmental Protection Agency (amongst other regulating agencies around the world) conducting audit testing, and the requirement that published road load values be repeatable within a specified range during these audits, the importance of answering these questions accurately is elevated. This paper studies these questions, and even offers methodology for addressing them.
2016-09-14
Technical Paper
2016-01-1888
Jie Hu, Yehui Li, Jun Cai, Richard Turkson, Feng Lin, Meiyun Qiao
Abstract This research is based on the Controller Area Network (CAN) bus, and briefly analyzed its communication protocol with reference to the layered model of Open System Interconnect Reference Model (OSI). Subsequently, a data acquisition system was designed and developed including a Vehicle Communication Interface (VCI) and a laptop. After the overall architecture was built, the communication mechanism of the VCI was studied. Furthermore, the lap top app was built using the layered design followed by the implementation of a scheme for data collection and experimentation involving the test driving of a real car on road. Finally, the driving style was identified by means of fuzzy reasoning and solving ambiguity based on fuzzy theory; via training the acceleration sample and forecast using the excellent learning and generalization ability of Support Vector Machine (SVM) for high-dimensional, finite samples.
2016-08-17
WIP Standard
ARP4553B
This SAE Aerospace Recommended Practice (ARP) is intended to provide design and qualification requirements for self-displacing hydraulic accumulators.

These requirements are intended to be included in the Producrement Specification for the accumulator. Those requirements identified by the use of "shall" are considered to be essential requirements; those requirements identified by the use of "should" are considered to be optional requirements for inclusion in the Specificaiton at the discretion of the Purchaser.

In addition, test methods for production acceptance and qualification purposes are provided.

The accumulator is intended for use in military aerospace hydraulic systems with rated pressures of up to 8000 psi (55,158 kPa) and of the following types as specified in SAE AS 5440: Type I: -65 to +160 °F (-54 to +71 °C) fluid temperature; Type II: -65 to +275 °F (-54 to +135 °C) fluid temperature.

2016-08-17
WIP Standard
J1401

This SAE Standard specifies the performance tests and requirements for hydraulic brake hose assemblies used in the hydraulic braking system of a road vehicle. It also specifies the methods used for identification of the hose manufacturer.

This document applies to brake hose assemblies made of a hose fabricated from yarn and natural or synthetic elastomers and assembled with metal end fittings for use with nonpetroleum-base brake fluids as specified in SAE J1703, SAE J1704 and SAE J1705.

The nominal internal diameter of the brake hose shall fall within one of the following values:

    a. less than 4 mm (1/8 in or less)
    b. 4 to 5 mm (3/16 in)

2016-08-17
WIP Standard
J2087
This SAE Standard provides test procedures, requirements, and guidelines for a daytime running light (DRL) function.
2016-08-16
WIP Standard
J183
This SAE Standard outlines the engine oil performance categories and classifications developed through the efforts of the Alliance of Automobile Manufacturers (Alliance), American Petroleum Institute (API), the American Society for Testing and Materials (ASTM), the Engine Manufacturers Association (EMA), International Lubricant Specification Advisory Committee (ILSAC) and SAE. The verbal descriptions by API and ASTM, along with prescribed test methods and limits are shown for active categories in Table 1 and obsolete categories in Table A1. Appendix A is a historical documentation of the obsolete categories. For purposes of this document, active categories are defined as those (a) for which the required test equipment and test support materials, including reference engine oils and reference fuels, are readily available, (b) for which ASTM or the test developer monitors precision for all tests, and (c) which are currently available for licensing by API EOLCS.
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