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2015-09-20
Book
This is the electronic format of the Journal.
2015-06-15
Technical Paper
2015-01-2283
Andrew Smith
iOS devices, including iPhones and iPads, are being used increasingly for professional and scientific applications. Using an iOS device for noise & vibration measurements is an application with many advantages, given its small size, availability, cost, and ease of operation. We have created a system for measuring noise level, logging noise over time, doing FFT frequency analysis of sound, and measuring speech intelligibility using iPhones and iPads as the host device. This provides a portable, cost-effective, and easy to deploy test and measurement system. The main area of concern for the performance of the system is the transducer, which in the case of the microphone was designed for the speech applications, rather than wide-band acoustical analysis, and for the gyroscope, for recognizing gross movement.
2015-06-15
Technical Paper
2015-01-2106
Mark Ray, Kaare Anderson
Cloud phase discrimination, with measurements of liquid water content (LWC) and ice water content (IWC) as well as the detection and discrimination of supercooled large droplets (SLD), are of primary importance due to several high-profile incidents over the past two decades. The UTC Aerospace Systems Optical Ice Detector (OID) is a prototype laser sensor intended to discriminate cloud phase, to quantify LWC and IWC, and to detect SLD and differentiate SLD conditions from Appendix C conditions. Phase discrimination is achieved through depolarization scattering measurements of a circularly polarized laser beam transmitted into the cloud. Optical extinction measurements indicate the liquid and ice water contents, while the differential backscatter from two distinct probe laser wavelengths infers an effective droplet size. The OID is designed to be flush-mounted with the aircraft skin and to sample the air stream beyond the boundary layer of the aircraft.
2015-06-15
Technical Paper
2015-01-2095
Wolfgang Hassler, Reinhard F.A. Puffing, Andreas Tramposch
Recent research on thermal ice protection of electrically heated restraining grids designed for applications in the environmental control system (ECS) of passenger aircraft is presented. The restraining grids consist of interlaced, electrically insulated wire (the topology of the grids is similar to that of tennis rackets) and are – in certain operation modes of the ECS – exposed to an airstream containing supercooled water droplets and/or ice particles. Heat is generated in the wire by an electric current, and the temperature of the wire is controlled with the aid of an electronic control system.
2015-06-15
Technical Paper
2015-01-2152
Earle Williams, Michael Donovan, David J. Smalley, Robert G. Hallowell, Elaine P. Griffin, Kenta T. Hood, Betty J. Bennett
MIT Lincoln Laboratory is tasked by the U.S. Federal Aviation Administration to investigate the use of the NEXRAD polarimetric radars for the remote sensing of icing conditions hazardous to aircraft. A critical aspect of the investigation concerns validation that has relied upon commercial airline icing pilot reports and a dedicated campaign of in situ flights in winter storms. During the month of February in 2012 and 2013, the CONVAIR 580 aircraft operated by the National Research Council of Canada was used for in situ validation of snowstorm characteristics under simultaneous observation by NEXRAD radars in Cleveland, Ohio and Buffalo, New York. The most anisotropic and easily distinguished winter targets to dual pol radar are ice crystals.
2015-06-15
Technical Paper
2015-01-2086
Matthew Grzych, Terrance Tritz, Jeanne Mason, Melissa Bravin, Anna Sharpsten
The significant problem of engine power-loss and damage associated with ice crystal icing (ICI) was discussed in Mason et al [1]. These engine events included engine surge, stall, flameout, rollback and compressor damage and were connected to the ingestion of high concentrations of ice crystals associated with deep convective clouds. Since that time, several industry and government collaborations have taken steps to address the many technological requirements identified by the Engine Harmonization Working Group (EHWG) in 2007 [2]. The EHWG identified the need for in-situ measurements of ice concentration and size distribution to aid in the development of engine test facilities and methods to simulate the environment. Researchers are also addressing a second technology requirement identified by the EHWG: fundamental studies on the physics of ice accretion in the engine. Both efforts require study environments to be similar to the ones that cause in-service engine events.
2015-06-15
Technical Paper
2015-01-2153
David Serke, Michael King, Andrew Reehorst
In early 2015, the NASA Glenn Research Center will conduct a field campaign based out of Cleveland, Ohio with 60 flight hours on the Twin Otter icing research aircraft. The purpose of the field campaign is to test several prototype algorithms meant to detect the location and severity of in-flight icing within the terminal airspace. The terminal airspace is currently defined as within 25 kilometers horizontal distance of the terminal, which in this case was Hopkins International Airport in Cleveland. Two new and improved algorithms have been developed and will be operated during the field campaign. The first is the 'NASA Icing Remote Sensing System', or NIRSS. NASA and the National Center for Atmospheric Research have developed this icing remote sensing technology which has demonstrated skill at detecting and classifying icing hazards in a vertical column above an instrumented ground station1,2.
2015-06-15
Technical Paper
2015-01-2112
Thomas Schlegl, Michael Moser, Hubert Zangl
We present a system of completely autarkic temperature and capacitive icing sensors for aircraft. The consequences of icing on aircraft are described, for example, in [1] and [2]. Flexible (i.e. bendable) sensors, which are truly wireless and do not require maintenance, are easily mounted to almost any point on the aircraft surface (e.g. wings, fuselage, rudder, elevator, etc.). The entire sensing unit has a size of less than 100 mm times 170 mm (3.397 in times 6.693 in). The overall thickness can be kept lower than 2 mm (0.079 in) at the current status of development. It comprises the sensor front-end, processing electronics, buffered solar harvesting and a low-power radio frequency transmitter. The system transmits measurement results via an RF link to a monitoring system, which comprises a receiver antenna and a receiver circuit located at a suitable position on the aircraft. The employed sensor principle was first suggested in [3].
2015-06-15
Technical Paper
2015-01-2248
Florian Pignol, Emiel Tijs, Daniel Fernandez Comesana, Daewoon Kim
It is important to determine the contribution of different engine components to the total sound perceived inside the cabin in order to apply an effective noise reduction treatment. Accelerometer or laser based vibration tests are usually performed, however, the radiated sound is not always captured accurately. Microphone based methods are strongly influenced by the many reflections and other sound sources inside the engine bay. Recently, it has been shown that engine radiation can be effectively measured using particle velocity sensors while the engine remains mounted in the car. Similar results were obtained as with a dismounted engine in an anechoic room. This paper is dedicated to the evaluation of the transfer path from the engine to the vehicle interior in order to calculate the sound pressure contribution of individual engine sections at the listener’s position. To achieve a good signal to noise ratio during acoustic transfer paths a novel monopole sound source was designed.
2015-06-15
Technical Paper
2015-01-2335
Scott Amman, Francois Charette, Paul Nicastri, John Huber, Brigitte richardson, Gint Puskorius, Yuksel Gur, Anthony Cooprider
Quantifying Hands-free Call Quality in an Automobile Hands-free phone use is the most utilized use case for vehicles equipped with infotainment systems with external microphones that support connection to phones and implement speech recognition. Critically then, achieving hands-free phone call quality in a vehicle is problematic due to the extremely noisy nature of the vehicle environment. Noise generated by wind, mechanical and structural, tire to road, passengers, engine/exhaust, HVAC air pressure and flow are all significant contributors and sources of noise. Other factors influencing the quality of the phone call include microphone placement, cabin acoustics, seat position of the talker, noise reduction of the hands-free system, etc. This paper describes the work done to develop procedures and metrics to quantify the effects that influence the hands-free phone call quality.
2015-06-15
Technical Paper
2015-01-2256
Colin Troth
This paper considers some aspects of rigid body dynamics of power trains with respect to noise and vibration (by definition a power train (PT) term here is an engine plus transmission). Rigid body concepts are very important in helping assess unwanted levels of flexibility of PT’s and attached ancillaries e.g. mounting brackets. Using rigid body concepts it is possible to define vibration and noise ‘entitlement’ to what can theoretically be achieved. Targets can then be to set based upon these entitlements. This can then lead to better more robust designs to achieve higher levels of refinement. Dedicated software and the use of generic 3 and 4 cylinder one litre in-line PT’s are used to aid this study which can be shown to adhere more to rigid body behaviour due to their compact designs and lower (frequency) dominant orders of excitation.
2015-06-15
Technical Paper
2015-01-2279
Giovanni Rinaldi, Chris Moon, Bret Engels
A unique Matlab-based coded engineering software tool (Time-Frequency Analyzer Core) was developed that allows users to process acquired time data to help in identifying sources and paths of noise and vibration (in the experience of the authors). The Time-Frequency Analyzer Core (TFAC) software does not replace commercial off the shelf software/hardware NV specific tools such as modal analysis, ODS, acoustic mapping, order tracking, etc., rather it aims at providing basic, yet powerful data inspection and comparison techniques in a single software tool that facilitate drawing conclusions and identifying most effective next steps. The features and advantages of using this software tool will be explained, along with a description of its application to a few different cases (automotive and off highway/agricultural).
2015-06-15
Technical Paper
2015-01-2281
Shrirang Deshpande, Randall Allemang
Spectral maps and order tracks are tools which are susceptible to improper sensor location on rotating machinery and to measurement noise. On a complex/large rotating system, the major behavior in a particular direction cannot be observed by using standard digital signal processing averaging techniques on different sensor outputs. Also, measurement noise cannot be reduced by applying averaging - due to the slew rate of the system. A newly developed technique tested on experimental data, is presented which uses singular value decomposition (SVD) as its basis to improve the observability of rotating systems. By using data acquired from multiple accelerometers on a machine, singular values – obtained from a SVD of the cross-power matrix at each 2-D point in the frequency-RPM domain – can be plotted in a color-map format similar to a RPM spectral map.
2015-06-15
Technical Paper
2015-01-2215
Thomas L. Lago
How to decrease noise and vibration exposure has been of interest for many years. Empirical data have verified that too high dose values can create multiple problems to a human body - often severe. Some years back, the European Machinery Directive has increased the responsibility for manufacturers and employers to make sure limits are complying with legislation. Classical technology often consists of passive solutions aiming at trying to cut back on noise and vibration levels. For low frequency, these methods are often lacking the needed performance especially if weight should be considered at the same time. A smart combination of passive and active techniques can make a real difference. Today, with possibilities for low cost and embedded electronics and the rapid development of new actuators, a vast range of applications are possible for this combined combat approach, with a financial advantage as well.
2015-06-15
Technical Paper
2015-01-2222
Nikos Zafeiropoulos, Marco Ballatore PhD, Andy Moorhouse PhD, Andy Mackay
Road noise forces can excite different structural resonances of the vehicle hence a high number of sensors required for observing and separating all the vibrations that are coherent with the cabin noise. Current reference sensor selection methods for feedforward road noise control result to high number of sensors. Therefore there is a necessity for reducing the number of sensors without degrading the performance of an ANC system. In the past coherence function analysis has been found to be useful for optimising the sensor location. Thus, in this case coherence function mapping was performed between an array of vibration sensors and a microphone in order to identify the locations on the structure with highly correlated with road bands in the compartment. A vehicle with an advanced suspension system was used for applying the method and defining some locations as reference signals for feedforward active road noise control.
2015-05-20
Book
This is the electronic format of the Journal.
2015-05-15
Book
This is the electronic format of the Journal.
2015-04-24
Article
Traffic gridlock, accident fatalities, and vehicle emissions are not good things. So the underlying challenge for the auto industry is to develop and use technologies appropriately for society. Matschi was the Thursday morning keynote speaker in the AVL theater inside Detroit’s Cobo Center at the 2015 SAE World Congress.
2015-04-24
Article
Initial focus is on battery, starter, and fuel pump to provide early warnings of impending issues with starting a car, as discussed in a 2015 SAE World Congress panel. The 4G connection in 2016 Chevrolets obtains data, cloud server holds the analysis algorithms.
2015-04-24
Article
As connectivity expands throughout the transportation industry, it’s transforming security from door locks to firewalls and antivirus programs. Aircraft and ground vehicle representatives discussed the topic during the “Technical Expert Panel Discussion: With connectivity, comes risks - cybersecurity and safety” at the 2015 SAE World Congress.
2015-04-24
Article
Car buyers want a human-machine interface that lets them bring in personal devices and perform all kinds of tasks whenever they want, and they don’t want to have to read a manual or spend time learning how to manage their many options. Panelists grappled with solutions to this vexing challenge during a 2015 SAE World Congress panel.
2015-04-24
WIP Standard
J1939DA
The J1939 Digital Annex The J1939 Digital Annex, introduced in August 2013, offers key J1939 technical data in an Electronic Spreadsheet that can be easily searched, sorted, and adapted to other formats. J1939DA contains all of the SPNs (parameters), PGNs (messages), and other J1939 data previously published in the SAE J1939 top level document. J1939DA also contains all of the SLOTs, Manufacturer ID Codes, NAME Functions, and Preferred Addresses previously published in the SAE J1939 top level and the J1939-71 document. J1939DA contains the complete technical details for all of the SPNs and PGNs previously published in the SAE J1939-71 document. It also includes the supporting descriptions and figures previously published in the SAE J1939-71 document. For other SPNs and PGNs which are published in a document other than SAE J1939-71, J1939DA lists only basic details along with a reference to the document that contains the complete technical details.
2015-04-24
WIP Standard
J211/1
This recommended practice outlines a series of performance recommendations, which concern the whole data channel. These recommendations are not subject to any variation and all of them shall be adhered to by any agency conducting tests to this practice. However, the method of demonstrating compliance with the recommendations is flexible and can be adapted to suit the needs of the particular equipment the agency is using. It is not intended that each recommendation be taken in a literal sense, as necessitating a single test to demonstrate that the recommendation is met. Rather, it is intended that any agency proposing to conduct tests to this practice shall be able to demonstrate that if such a single test could be and were carried out, then their equipment would meet the recommendations. This demonstration shall be undertaken on the basis of reasonable deductions from evidence in their possession, such as the results of partial tests.
2015-04-24
WIP Standard
J2744
This document presents the requirements for a build-in service port to be used in vehicles intended to comply with Enhanced Evaporative Emission Requirements. The primary function of the Service Port (Valve Assembly-Evaporative Emission Canister Purge Harness Service) is to provide non-destructive access to the evaporative emissions system to enable testing of the integrity of the system. The Service Port is used to introduce air pressure or fuel vapors into, or evacuate them out of, the system. This access may be used for the following evaluations: Evaporative System Certifications Canister Loading and Pumping End-of-line Testing System Integrity Service (e.g. OBD MIL on) Leak Location and Repair Verification In-Use Compliance Testing Canister Loading and Purging Inspection/Maintenance Testing System Integrity and Purge Check
2015-04-23
WIP Standard
J1939/15
This document describes a physical layer utilizing Unshielded Twisted Pair (UTP) cable with extended stub lengths for flexibility in ECU placement and network topology. Also, connectors are not specified. CAN controllers are now available which support the newly introduced CAN Flexible Data Rate Frame format (known as “CAN FD”). These controllers, when used on SAE J1939-15 networks, must be restricted to use only the Classical Frame format compliant to ISO 11989-1 (2003). These SAE Recommended Practices are intended for light- and heavy-duty vehicles on- or off-road as well as appropriate stationary applications which use vehicle derived components (e.g., generator sets). Vehicles of interest include but are not limited to: on- and off-highway trucks and their trailers; construction equipment; and agricultural equipment and implements.
2015-04-22
Article
Inventor and futurist Ray Kurzweil sees a remarkable century with autonomous vehicles transporting smarter, healthier persons to various destinations.
2015-04-22
Article
Automotive planners and developers are working overtime to provide more autonomous features and functions, but there’s still plenty of uncertainty surrounding driverless cars.
2015-04-21
Article
Although 30% of traffic fatalities are alcohol-related, and electronic Driver Alcohol Detection System for Safety has appeal, more targeted approaches to reducing them are being taken by car makers. Programs aimed at reducing teen driver accidents and death were described at the 25th annual World Traffic Safety Symposium during the New York Auto Show.
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