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Journal Article

Research on Measurement Method of Road Gradient and Altitude by On-Road Driving

2009-04-20
2009-01-1116
Exhaust emissions from a vehicle under road driving condition is affected by the control state of ECU (Engine Control Unit). This control state highly depends on the driving force of the vehicle. The driving force is nearly equal to the driving resistance, which is the sum of the acceleration resistance, the air resistance, the rolling resistance and the gradient resistance. Although it is essential to take an accurate measurement of the road gradient, it is quite difficult to evaluate the gradient resistance in testing on-road driving. In this study, the measurement methods of the road gradient and the altitude with GPS, gyro sensor and height sensor are reported. The road gradient under the on-road driving condition is evaluated by the combination of measuring the pitch angle with the gyro sensor and measuring the vehicle gradient with the two height sensors. Verifying of this method, the altitude of the driving test route is also evaluated.
Technical Paper

Application of Virtual SEA for the Prediction of Acoustic Performance of Cockpit

2009-04-20
2009-01-0767
Not only for the carmakers but also for the automotive parts suppliers, cost reduction and short development cycle are strongly required to survive in highly competitive market. The simulation models predicting acoustic performance of cockpit module at early design stage could be a part of time-saving and cost-effective solution for those demands. Via experimental, analytical, and virtual statistical energy analysis (SEA) approach, the simulation models of cockpit module predicting acoustic performance are developed and validated. Recently proposed virtual SEA using FE models from crash analysis are useful to reduce the ambiguity of SEA modeling which could make a big difference in the result. The SEA models simulate the transmission loss tests of a cockpit module attached with several kinds of acoustical treatments between two connected reverberation chambers.
Journal Article

Optimum Guide Position Design of a Cockpit Module for Decreasing the Permanent Deformation

2010-04-12
2010-01-0393
The noise of interior plastic parts has been one of the major driving factors in the design of automotive interior assemblies. This phenomenon is one of the major contributors to the perceived quality in a vehicle. The noise is caused by interior plastic parts and other parts as a result of permanent deformation. Traditionally, noise issues have been identified and rectified through extensive hardware testing. However, to reduce the product development cycle and minimize the number of costly hardware builds, hardware testing must rely on engineering analysis and upfront simulation in the design cycle. In this paper, an analytical study to reduce permanent deformation in a cockpit module is presented. The analytical investigation utilizes a novel and practical methodology, which is implemented through the software tools, ABAQUS and iSight, for the identification and minimization of permanent deformation.
Journal Article

Car-to-X Simulation Environment for Comprehensive Design Space Exploration Verification and Test

2010-04-12
2010-01-0451
A future car-to-x communication system has to fulfil a lot of different requirements concerning high performance and functionality that are given by the field of application. To be able to optimize the system architecture regarding these constraints an intensive architecture evaluation and investigation is necessary. Within this paper a simulative approach for comprehensive design space exploration, verification, and test of a car-to-x communication unit is presented. The proposed simulation environment allows for a flexible adaption to the test case by being able to interconnect an arbitrary number of simulators of different type and different granularity. As a novelty complete embedded car-to-x systems can be investigated by integrating several SystemC based architecture models into an environmental simulation and observing their behavior and interaction.
Technical Paper

Statistical Modeling of Fatigue Crack Growth in Wing Skin Fastener Holes

2010-04-12
2010-01-0202
Estimation and prediction of residual life and reliability are serious concerns in life cycle management for aging structures. Laboratory testing replicating fatigue loading for a typical military aircraft wing skin was undertaken. Specimens were tested until their fatigue life expended reached 100% of the component fatigue life. Then, scanning electron microscopy was used to quantify the size and location of fatigue cracks within the high stress regions of simulated fastener holes. Distributions for crack size, nearest neighbor distances, and spatial location were characterized statistically in order to estimate residual life and to provide input for life cycle management. Insights into crack initiation and growth are also provided.
Technical Paper

Tribological Evaluation of the Aviation Kerosene for Use in CI Engines

2009-11-02
2009-01-2804
To reduce the fuel related logistic burden, NATO Armed Forces are advancing the use of a single fuel for both aircraft and ground equipment. To this end, F-34 is replacing distillate diesel fuel in many applications. Yet, unacceptable wear due to poor lubricity was illustrated by tests conducted with kerosene on High Frequency Reciprocating Rig. Therefore, HFRR tests were performed with fatty acid methyl esters of sunflower, palm, cotton-seed, tobacco-seed, olive, rape-seed and used frying oils, at volume concentrations from 0.05% to 0.6%. This study showed that the biodiesels used, produced a significant decrease in the wear scar diameter at concentrations of 0.2% to 0.4 %. Biodiesels derived from non-polyunsaturated oils, such as palm and olive gave better lubrication at certain concentrations.
Technical Paper

Aeroelastic Design of a Joined-Wing UAV

2009-11-10
2009-01-3150
Aim of this study is the development of an integrated methodology able to support the structural design of an UAV demonstrator, having a joined-wing configuration and a high structural flexibility. HAPD (High Altitude Performance Demonstrator) is an UAV multi-mission, very light vehicle under development at CIRA, the Italian Aerospace Research Centre. HAPD structure is redundant as regards constraints, so the internal forces depend upon the stiffness distribution. In addition the evaluation of flight loads has to be performed without neglecting the flexibility of the structure. Because of the extreme unconventionality of the configuration the design of the primary structures has been widely affected by aeroelastic analyses.
Technical Paper

Quantifying the Fuel Consumption Penalties for an Operational Contrail Avoidance System

2009-11-10
2009-01-3151
Recent work has shown that when an aircraft encounters ambient ice-supersaturated conditions (where contrails may form and persist), it may be possible to avoid contrail formation by shifting cruise altitude up or down 2000 feet. If an aircraft's cruise altitude is shifted from the optimal profile during a portion of the mission, fuel consumption increases. Because on average approximately 20% of distance flown by commercial airliners is through ice-supersaturated regions, this study quantifies the fuel burn penalties for the notional scenario of flying the same fraction of cruise at altitude displacements of +2000, -2000, and -4000 ft. Present aircraft performance data was used to generate accurate fuel burn penalty estimates. This study finds that the net penalties for existing aircraft to fly contrail avoidance shifts vary between 0.2% and 0.7% increase in block fuel consumption.
Technical Paper

Torino Piemonte Aerospace (TPA) Project - Strategic Planning Model for SMEs

2009-11-10
2009-01-3153
Torino Piemonte Aerospace project (TPA) implemented a scientific, strategic planning method that simultaneously supports selected aerospace Piemonte Region (located in North-Western Italy) SMEs in their internationalisation process and offers the world aerospace community a competitive Supply Chain for professional procurement and for world-class partners and suppliers identification. Strategic Planning Framework adopted by TPA is a disciplinary tool which measured the competitive strength of the Piemonte aerospace cluster (TPA companies) and analyzed the external environment (market trends, business models, strategic assets). Within the limits of Competitive Positioning analysis, TPA Team performed the selection of the 66 top class aerospace and defence companies able to match buyers' needs and interact with international markets.
Journal Article

Managing Aircraft Simulation Requirements with Content-Based Image Retrieval

2009-11-10
2009-01-3149
Requirements analysis for aircraft simulators is often driven by photographs and videos of the actual aircraft. An engineer may gather and organize hundreds or even thousands of source photos of various instruments and devices unique to the aircraft. Managing all of this source information and referencing it to generate software requirements can be challenging and time-consuming. This paper explores Content Based Image Retrieval (CBIR) techniques to automatically process and search those images to generate basic requirements and to facilitate reuse. An unsupervised clustering algorithm groups source images based on minimal user input. Images processed in this way can also be queried by image similarity, thereby allowing project managers to find common source material among projects. The effectiveness of these techniques is demonstrated on an example cockpit.
Journal Article

Evaluation of the Use of a Head Worn Display (HWD) for Flight Support in the Commercial Flight Deck

2009-11-10
2009-01-3144
This study compared the performance of pilots flying a series of approach and landings under each of three conditions: using standard 737-NG flight deck displays only, using those displays with an optical head up display (HUD), and using those displays with a head worn display (HWD) depicting the same symbology as the HUD. Display condition had no effect on pilots' normal landing flight profiles or successful avoidance of a runway incursion. However, pilots reported decreased situation awareness and increased perceived workload when using the HWD as compared to the other two conditions. Pilot comments suggested that the poorer ratings for HWD were attributed to physical characteristics of the hardware and noticeable head-tracking latency. The results indicate that while the HWD technology still needs more refinement, the near-to-eye display concept is a viable alternative to a HUD.
Technical Paper

MIL-STD-1553 Physical Layer for Time-Triggered Networks

2009-11-10
2009-01-3147
Time Triggered networking technologies such as TTP (Time Triggered Protocol) are beginning to be used in critical aerospace applications such as flight controls. While TTP provides stringent specifications for determinism and fault tolerance, it does not define a physical layer. TTP's “de facto” physical layer, RS-485, includes shortcomings in a number of areas. These include a relatively low minimum transmitter voltage, low receiver threshold, along with a lack of specificity in a number of areas. The latter include bus signal levels, transmitter zero-crossing distortion and receiver zero-crossing tolerance, isolation method, terminal output noise, common mode and noise rejection, and input impedance. MIL-STD-1553, which has been deployed in flight and mission critical military applications for decades, defines a highly proven and robust physical layer. This paper presents MIL-STD-1553's physical layer as a candidate for use with TTP.
Technical Paper

Photometric and Colorimetric Measurement Procedures for Airborne Electronic Flat Panel Displays — SAE ARP 4260

2009-11-10
2009-01-3143
SAE ARP 4260 Photometric and Colorimetric Measurement Procedures for Airborne Electronic Flat Panel Displays [1] has recently been revised. This new revision reaffirms that ARP 4260 is pertinent to the aviation industry, changes the content to keep up with the state of the art, and adds clarification where needed. ARP 4260 contains methods used to measure the optical performance of airborne electronic flat panel display systems and is referenced in SAE ARP 4256, Design Objectives for Liquid Crystal Displays for Part 25 (Transport) Aircraft [2] and in SAE AS 8034, Minimum Performance Standard for Airborne Multipurpose Electronic Displays [3].
Journal Article

Head Up Display Performance Improvements and Cost Reductions through the Application of Non-conventional Engineering Solutions

2009-11-10
2009-01-3142
This paper describes displays realized by the use of radically new optical and image source design techniques that have facilitated very significant performance improvements beyond those previously achieved. These improvements are not only in respect of size, weight, volume and cost for a given optical performance, but also in the characteristics that currently limit, or in some cases prohibit, the use of such displays in many cockpit applications. Displays that have been realized and tested through the implementation of these new techniques are described and their performance in laboratory and flight trials discussed, together with a discussion of the way ahead for further progress in their development.
Journal Article

Advanced Electrical Signature Analysis of Aircraft Electrical Generators

2009-11-10
2009-01-3162
The electrical and mechanical failures (such as bearing and winding failures) combine to cause premature failures of the generators, which become a flight safety issue forcing the crew to land as soon as practical. Currently, diagnostic / prognostic technologies are not implemented for aircraft generators where repairs are time consuming and its costs are high. This paper presents the development of feature extraction and diagnostic algorithms to ultimately 1) differentiate between these failure modes and normal aircraft operational modes; and 2) determine the degree of damage of a generator. Electrical signature analysis based features were developed to distinguish between healthy and degraded generators while taking into account their operating conditions. The diagnostic algorithms were developed to have a high fault / high-hour detection rate along with a low false alarm rate.
Journal Article

Applying Poincaré Plots for Evaluating the Health State of Aircraft Generators

2009-11-10
2009-01-3161
This paper explores the use of Poincaré plots to study signal variability of Navy P-3 aircraft generators. The method, which was inspired from nonlinear dynamics for analyzing interval sequences, is a technique used to plot each interval against the subsequent interval of the signal from different points of view. The geometry of the plots reveals salient features among new, low-usage, and high-usage generators. In addition to its simple visual interpretation, quantitative descriptors were explored to assess the degree of degradation of the overall system health state. The results suggest that accurate health state predictions can be achieved if baseline data can be collected.
Technical Paper

High Altitude Platforms for Telecommunications: Design Methodology

2009-11-10
2009-01-3159
High Altitude Platforms (HAPs) represents an appealing solution to deliver low cost broadband access to telecommunication (TLC) networks. However, this potential can be disclosed only if a proper technology is identified in the design of airships and aircrafts. This paper first presents the innovative services which can be provided by a fleet of HAPs in the field of information and communication technology (ICT), and then a novel approach to a modular the design of HAPs is presented. In particular, this study consists of a theoretical investigation and energetic design of an HAP derived from a new class of stratospheric airship for the production of energy at high quote. In practice the energy is harvested by photovoltaic panels and stored in hydrogen fuel cells. We denote this new technology with the acronym P.S.I.C.H.E. (Photovoltaic Space Island for Conversion of Hydrogen as Energy vector).
Technical Paper

ROPTALMU - A New Concept of Crawling Portable Robotic System for Wing Spars Drilling

2009-11-10
2009-01-3158
In this paper a new concept of portable-crawler robotic system for wing spars drilling during their assembly phase will be presented. The solution developed, named ROPTALMU, consists of a drilling robot that is brought along the shop floor to the wing assembly tooling by means of an automated guided vehicle (AGV). Once in front of the tooling, the drilling robot is detached from the AGV and fixed securely and accurately to the tooling structure. Then a first set of holes is drilled inside the robot's reach. After this, in order to work in another product's working zone, the robot is able to walk automatically along the tooling. Once the work finished in the whole product, the robot is put again in the AGV and brought to the next product tooling. The system has been conceived so that it is able to adapt to a wide variety (different families) of wing spars performing drilling tasks on materials such as aluminum, CF and titanium.
Technical Paper

Automated Fastening of Aircraft Cargo Door Structures with a Standard Articulating Robot System

2009-11-10
2009-01-3157
The demand of flexible and cost-efficient solutions for automated fastening systems inspired us to develop the robot and end-effector technology to fulfil the customer's requirement for a highly accurate, automated robot based drill and fastening system for an aerospace application. This paper describes an innovative robot cell for drilling and solid riveting installation in cargo door structures of a single aisle aircraft at EUROCOPTER in Germany. The required absolute positioning accuracy is reached by using a special compensation package for the robot that was developed by BROETJE-Automation. Our customer's application required a completely new type of end-effector; installing solid rivets and capable of operating within the inner structure of the cargo doors. This solution demonstrates how standard robots equipped with a mature compensation method by BROETJE-Automation resulted in a highly flexible and cost-efficient light weight automation response.
Technical Paper

Pinch Bolt Injector

2009-11-10
2009-01-3156
This paper will cover the design of the pinch bolt injector used on the A380 panel to stringer joining machines #9 and #10. The bolt injector was designed to decrease bolt insertion cycle time, increase reliability and incorporate a fully automated bolt purge system. This paper will cover how the injector handles bolt diameters from 1/4″-1/2″ and how it helped increase the machines' bolt insertion rate from 5.5 bolts per minute to 8 bolts per minute
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