No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Development of In-wheel Motor Noise Reduction for Electric Vehicles Using Active Noise Control(ANC)
This paper describes the concept of adaptive noise cancelling, an alternative method of estimating signals corrupted by additive noise or interference. The method uses a "primary" input containing the corrupted signal and a "reference" input containing noise correlated in some unknown way with the primary noise. The reference input is adaptively filtered and subtracted from the primary input to obtain the signal estimate. Adaptive filtering before subtraction allows the treatment of inputs that are deterministic or stochastic, stationary or time variable. Wiener solutions are developed to describe asymptotic adaptive performance and output signal-to-noise ratio for stationary stochastic inputs, including single and multiple reference inputs. These solutions show that when the reference input is free of signal and certain other conditions are met noise in the primary input can be essentiany eliminated without signal distortion. It is further shown that in treating periodic interference the adaptive noise canceller acts as a notch filter with narrow bandwidth, infinite null, and the capability of tracking the exact frequency of the interference; in this case the canceller behaves as a linear, time-invariant system, with the adaptive filter converging on a dynamic rather than a static solution. Experimental results are presented that illustrate the usefulness of the adaptive noise cancelling technique in a variety of practical applications. These applications include the cancelling of various forms of periodic interference in electrocardiography, the cancelling of periodic interference in speech signals, and the cancelling of broad-band interference in the side-lobes of an antenna array. In further experiments it is shown that a sine wave and Gaussian noise can be separated by using a reference input that is a delayed version of the primary input. Suggested applications include the elimination of tape hum or turntable rumble during the playback of recorded broad-band signals and the automatic detection of very-low-level periodic signals masked by broad-band noise.
Das Ingenieurbüro Evomotiv GmbH und die University of Applied Sciences Offenburg entwickeln seit Ende 2008 ein Antriebskonzept für leichte Stadtfahrzeuge. Ziel des Elektroantriebs ist die Serientauglichkeit der hochintegrierten, getriebelosen und eisenfreien Radnabenmotoren. Das Bundesministerium für Wirtschaft und Technologie (BMWi) unterstützt das Projekt. Das Konzept des Radnabenmotors erhielt 2006 den Bosch—Innovationspreis und gewann 2008 den Shell-Eco-Marathon. Im Jahr 2011 wird Evomotiv mit seinen Partnern erste Prototypen auf der Straße testen.
This paper represents a short review on active noise control (ANC) with the emphasis on ANC systems implemented by using FxLMS adaptation algorithm. The physical mechanism behind active noise control, based on which local silence zones can be created is detailed. Basic configurations for realization of ANC systems are then introduced. It is shown that FxLMS algorithm has been widely used in different types of ANC systems. Available theoretical work on analysis of FxLMS-based ANC systems is reviewed. Shortcomings of available theoretical findings are discussed. Finally, recent advances in theoretical analysis of FxLMS-based ANC systems are introduced. These advances can be considered as the recent contributions made by the authors. Simulation results are also used to demonstrate the validity of the theoretical findings.
Der Rad-Straßen-Simulator RASS des Fraunhofer LBF in Darmstadt ist nicht nur eine neue Generation in der Prüfmaschinen technik, sondern auch ein Bindeglied zwischen der traditionellen ZWARP-Technik und zukünftigen Merkmalen weiter verbesserter Verfahren in der Laborsimulation. Die Zuverlässigkeitsbewertung von neuen Radkonstruk tionen lässt sich mit dem neuen Konzept aus einer weitgehend realistischen Betriebslastensimulation ableiten.
Vehicle refinement should include a consideration of the discomfort likely to be caused by vibration. This paper reviews the measurement, the evaluation, and the assessment of vehicle vibration felt by drivers and passengers.The feeling of vibration that gives rise to judgements of vibration discomfort can be predicted using evaluation procedures that take into account human sensitivity to different magnitudes, frequencies, directions, and durations of vibration. The evaluation methods make it possible to optimise vehicles via dynamic modelling before the production of prototypes and they assist the testing and optimisation of prototypes and production vehicles.Vibration evaluation provides imperfect predictions of discomfort when driver or passenger opinion is influenced by factors other than the vibration that is being measured and evaluated. Vibration evaluation can detect changes that are not detectable subjectively since smaller changes can be detected by measurement and evaluation than by subjective assessment.
The purpose of this device is to reduce ambient noise at the ear by using a headset to generate a sound pressure equal in magnitude and opposite in phase to the noise. This paper reports the results of pure‐tone experiments. A microphone was mounted on each earphone of a conventional military headset. A two‐channel system was used in which the signal from each microphone was passed through an amplifier and a phase‐shifting network and was then applied to its earphone. The subject wore the headset in a pure‐tone field and adjusted the amplifications and phase shifts for minimum loudness. The signal produced by each earphone was then substantially equal in magnitude and opposite in phase to the sound coming through and under its earcap. The proper amplification and phase shift are frequency‐dependent and vary among subjects. Eight complete measurements were made on two subjects. The mean values of the two parameters were computed for each frequency. Calculations indicate that a device having these mean characteristics would provide a noise reduction between 100 and 1200 cps that averages 10 db more than is provided by the earcap alone.
From the Publisher:Active noise control (ANC) is rapidly becoming the most effective way to reduce noises that can otherwise be very difficult and expensive to control. ANC is achieved by introducing a canceling "anti-noise" wave through an appropriate array of secondary sources. When applied accurately, ANC can provide effective solutions to noise-related problems in a broad range of areas, including manufacturing and industrial operations as well as consumer products. Consequently, ANC research and development has become an important focus of both industrial applications and engineering research. Active Noise Control Systems: Algorithms and DSP Implementations introduces the basic concepts of ANC with an emphasis on digital signal processing (DSP) hardware and adaptive signal processing algorithms, both of which have come into prominence within the last decade. The authors emphasize the practical aspects of ANC systems by combining the principles of adaptive signal processing with both experimental results and practical implementation. Applications are cited in many fields and encompass all types of noise media, including air-acoustic, hydroacoustic, vibrations, and others. The specific implementation stressed is based on the TMS320 family of signal processors from Texas Instruments, which are the most widely used worldwide. Coverage of theory includes concise derivations and analyses of commonly used adaptive structures and algorithms for active noise control applications, which are enhanced by the inclusion of a floppy disk featuring C and assembly programs for implementing many ANC systems. Mathematical representations are employed and the source code included on the disk is in a form that is easily accessible to anyone using the book. For practicing engineers, researchers, and advanced students in signal processing, Active Noise Control Systems: Algorithms and DSP Implementations will serve as a comprehensive, state-of-the-art text/reference on this important and rapidly de
On the Analysis and Design of In-wheel Motor for Vehicle Application, Doctoral Dissertation
- S Perekopskiy
A Study on the Development of In-wheel Motor Noise by Using the Active Noise Control
- H K Lee
- C S Oh
- M S Kim
- J H Lee
Lohner-Porsche-Fahrzeuge die ihrer Zeit weit vorraus waren, Posted on Autowallpaper.de, Markus Keller, Betrieb von Internetseiten und Internetdienstleistungen
- M Keller