| 1. |
- Källström, Elisabeth, et al.
(författare)
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Analysis of Automatic Transmission Vibration for Clutch Slippage Detection
- 2015
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Ingår i: 22nd International Congress on Sound and Vibration 2015 (ICSV 22). - : Curran Associates, Inc.. - 9781510809031
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Konferensbidrag (refereegranskat)abstract
- Heavy duty construction equipment is generally equipped with automatic transmission enablingto change gear ratio automatically. The clutches in an automatic transmission transfer torquefrom the engine to the gearbox and clutch failures may result in costly downtime of constructionequipment. To prevent costly downtime of construction equipment, condition monitoring in com-bination with condition based maintenance may be utilized. Different sensor data are collectedon a machine that enables condition monitoring. Vibration have been measured on an automatictransmission in a construction equipment machine during controlled driving sessions, with andwithout clutch slippage, on a test track. An initial investigation of the vibration measured on theautomatic transmission have been carried out with the purpose to find out if the vibration maycontain reliable information related to clutch slippage considered to be abnormal. Initial signalanalysis of the data have been carried out using Spectrogram and Spectral Kurtosis methods. Theresults indicate that information related to abnormal clutch slippage may be extracted from vibra-tion measured on an automatic transmission in a construction equipment machine.
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| 2. |
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| 3. |
- Källström, Elisabeth, et al.
(författare)
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Identification of vibration properties of heavy duty machine driveline parts as a base for adequate condition monitoring: Axle
- 2016
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Ingår i: ICSV 2016 - 23rd International Congress on Sound and Vibration. - : INT INST ACOUSTICS & VIBRATION. - 9789609922623
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Konferensbidrag (refereegranskat)abstract
- With increasing complexities in the heavy duty construction equipment, early fault detection of certain components in the machine becomes more and more challenging due to too many fault code generated when a failure occurs. The axle is one of such component. The axle transfers driving torque from the transmission to the wheels and axle failure may result in costly downtime of construction equipment. To reduce service cost and to improve uptime, adequate condition monitoring based on sensor data from the axle is considered. Vibration is measured on the axle. Analysis of the data has been carried out using adequate signal processing methods. The results indicate that the vibration properties of the axle are relevant for early fault detection of the axle. In this way; the health of the axle may be continuously monitored on-board using the vibration information and if the axle health starts to degrade a service and/or repair may be scheduled well in advance of a potential axle failure and in that way the downtime of a machine may be reduced.
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| 4. |
- Källström, Elisabeth, et al.
(författare)
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Identification of vibration properties of heavy duty machine driveline parts as a base for adequate condition monitoring: Torque converter
- 2016
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Ingår i: ICSV 2016 - 23rd International Congress on Sound and Vibration. - : INT INST ACOUSTICS & VIBRATION. - 9789609922623
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Konferensbidrag (refereegranskat)abstract
- Improving uptime is paramount in the heavy duty construction equipment business. Failure ofcritical components in the heavy duty machine may lead to unnecessary stops and expensive downtime. The torque converter, a complex omponent of the driveline, transmits and multiplies torque from the engine to the gearbox, and its failure may not only lead to the machine standing still but may also lead to damage of other parts of the automatic transmission. For adequate condition monitoring of the torque converter, different sensor data are measured on a construction equipment machine during controlled driving sessions. Vibration has been measured on the torque converter. An initial investigation of the vibration measured on the torque converter has been carried out to identify its vibration properties in order to enable its health monitoring to prevent failure. Initial signal analysis of the data have been carried out using Order Power Spectrum and Order Modulation Spectrum methods. The results indicate that the torque converter vibration properties contain information relevant for early fault detection.
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| 5. |
- Källström, Elisabeth, et al.
(författare)
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On-board Clutch Slippage Detection and Diagnosis in Heavy Duty Machine
- 2018
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Ingår i: International Journal of Prognostics and Health Management. - : PHM Society. - 2153-2648. ; 9:1
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Tidskriftsartikel (refereegranskat)abstract
- In order to reduce unnecessary stops and expensive downtime originating from clutch failure of construction equipment machines; adequate real time sensor data measured on the machinein combination with feature extraction and classification methods may be utilized.This paper, based on a study at Volvo Construction Equipment,presents a framework with feature extraction methods and an anomaly detection module combined with Case-Based Reasoning (CBR) for on-board clutch slippage detection and diagnosis in a heavy duty equipment. The feature extraction methods used are Moving Average Square Value Filtering (MASVF) and a measure of the fourth order statistical properties of the signals implemented as continuous queries over data streams. The anomaly detection module has two components,the Gaussian Mixture Model (GMM) and the Logistics Regression classifier. CBR is a learning approach that classifies faults by creating a new solution for a new fault case from the solution of the previous fault cases. Through use of a data stream management system and continuous queries (CQs), the anomaly detection module continuously waits for a clutch slippage event detected by the feature extraction methods, the query returns a set of features which activates the anomaly detection module. The first component of the anomaly detection module trains a GMM to extracted features while the second component uses a Logistic Regression classifier for classifying normal and anomalous data. When an anomalyis detected, the Case-Based diagnosis module is activated for fault severity estimation.
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| 6. |
- Larsson, Martin, et al.
(författare)
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A FEEDFORWARD ACTIVE NOISE CONTROL SYSTEM FOR DUCTS USING A PASSIVE SILENCER TO REDUCE ACOUSTIC FEEDBACK
- 2007
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Konferensbidrag (refereegranskat)abstract
- Ventilation systems installed in buildings usually generate low-frequency noise because the passive silencers commonly used to attenuate the ventilation noise are not effective in the low-frequency range. A method proven to effectively reduce low-frequency noise in a wide variety of applications is active noise control (ANC). A feedforward ANC system applied to duct noise normally uses a reference microphone, a control unit, a loudspeaker to generate the secondary noise created by the controller, and an error microphone. The secondary noise generated by the loudspeaker will travel both downstream canceling the primary noise, and upstream to the reference microphone, i.e. acoustic feedback. The acoustic feedback may result in performance reduction and stability problems of the control system. Common approaches to solve the feedback problem result in more complex controller structures and/or system configurations than the simple feedforward controller, e.g. introducing a feedback cancellation filter in the controller in parallel with the acoustic feedback path, or using a dual-microphone reference sensing system. This paper presents a simple approach to reduce the acoustic feedback by using a basic feedforward controller in combination with a passive silencer. Simulations show that efficient acoustic feedback cancellation is achieved by using a passive silencer. In the experimental setup another advantage with using a passive silencer is that the frequency response function of the forward path, which is to be estimated, is smoother, i.e. most of the dominant frequency peaks in the frequency response function when not using a passive silencer is reduced. This in turn results in an acoustic path that is less complex to estimate with high accuracy using an adaptive FIR filter steered with the LMS algorithm.
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| 7. |
- Larsson, Martin, et al.
(författare)
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A Module Based Active Noise Control System for Ventilation Systems, Part I : Influence of Measurement Noise on the Performance and Convergence of the Filtered-x LMS Algorithm
- 2009
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Ingår i: International Journal of Acoustics and Vibration. - : International Institute of Acoustics and Vibration. - 1027-5851 .- 2415-1408. ; 14:4, s. 188-195
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Tidskriftsartikel (refereegranskat)abstract
- Low noise level is an essential feature when installing ventilation systems today. To achieve attenuation over a broad frequency range, the passive silencers traditionally used to attenuate ventilation noise can be combined with an active noise control (ANC) system. To insure reliable operation and desirable levels of attenuation when applying ANC to duct noise, it is highly important to be able to suppress the contamination of the microphone signals due to the turbulent pressure fluctuations arising as the microphones are exposed to the airflow in the duct. This paper is the first in a series of two, that treats the problem of turbulence induced noise originating from the airflow inside the ducts. Part I is concerned with theoretical and experimental investigations of the influence of the turbulence induced noise on the adaptive algorithm in the ANC system. Part II is concerned with design and investigations of microphone installations for turbulence suppression and results concerning the performance of an ANC system with the different microphone installations are presented. Some of the results were obtained at an acoustic laboratory according to an ISO-standard. The attenuation achieved with ANC was approximately 15-25 dB between 50-315 Hz even for airflow speeds up to 20 m/s.
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| 8. |
- Larsson, Martin, et al.
(författare)
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A Module Based Active Noise Control System for Ventilation Systems, Part II : Performance Evaluation
- 2009
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Ingår i: International Journal of Acoustics and Vibration. - : International Institute of Acoustics and Vibration. - 1027-5851 .- 2415-1408. ; 14:4, s. 196-206
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Tidskriftsartikel (refereegranskat)abstract
- To utilize the full noise attenuation potential of an active noise control (ANC) system applied to duct noise, it is important to be able to minimize the turbulence induced noise in the microphone signals. This is the second paper in a series of two, that treats the problem of turbulence induced noise originating from the airflow inside the ducts, when applying ANC to ducts. Part I contains theoretical and experimental investigations of the influence of the turbulence induced noise on the filtered-x LMS algorithm used in the ANC system. Part II (the present paper) is concerned with design and investigations of microphone installations which produces a sufficient amount of turbulence suppression while also meeting industry requirements. These requirements are, for example, that the microphone installations should be based on standard ventilation parts, and that they should be easily installed and maintained. Furthermore, results concerning the performance of an ANC system with different microphone installations are presented. Some of the results were obtained at an acoustic laboratory according to an ISO standard. The attenuation achieved with ANC was approximately 15-25 dB between 50-315 Hz even for airflow speeds up to 20 m/s.
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| 9. |
- Larsson, Martin, et al.
(författare)
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A Module Based Active Noise Control System for Ventilation Systems, Part II : Performance Evaluation
- 2009
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Ingår i: International Journal of Acoustics and Vibration. - : International Institute of Acoustics and Vibration (IIAV). - 1027-5851 .- 2415-1408. ; 14:4, s. 196-206
-
Tidskriftsartikel (refereegranskat)abstract
- To utilize the full noise-attenuation potential of an active noise control (ANC) system applied to duct noise, it is important to be able to minimize the turbulence-induced noise in the microphone signals. This is the second paper in a series of two, that treats the problem of turbulence-induced noise originating from the airflow inside the ducts, when applying ANC to ducts. Part I contains theoretical and experimental investigations of the influence of the turbulence-induced noise on the filtered-x LMS algorithm used in the ANC system. Part II (the present paper) is concerned with the design and investigations of microphone installations, which produce a sufficient amount of turbulence suppression while also meeting industry requirements. These requirements are, for example, that the microphone installations should be based on standard ventilation parts, and that they should be easily installed and maintained. Furthermore, results concerning the performance of an ANC system with different microphone installations are presented. Some of the results were obtained at an acoustic laboratory according to an ISO standard. The attenuation achieved with ANC was approximately 15-25 dB between 50-315 Hz, even for airflow speeds up to 20 m/s.
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| 10. |
- Larsson, Martin, et al.
(författare)
-
A Module Based Active Noise ControlSystem for Ventilation Systems, Part I : Influence of Measurement Noise on the Performance and Con-vergence of the Filtered-x LMS Algorithm
- 2009
-
Ingår i: International Journal of Acoustics and Vibration. - : International Institute of Acoustics and Vibration (IIAV). - 1027-5851 .- 2415-1408. ; 14:4, s. 188-195
-
Tidskriftsartikel (refereegranskat)abstract
- Low noise level is an essential feature when installing ventilation systems today. To achieve attenuation over a broad frequency range, the passive silencers traditionally used to attenuate ventilation noise can be combined with an active noise control (ANC) system. To insure reliable operation and desirable levels of attenuation when applying ANC to duct noise, it is highly important to be able to suppress the contamination of the microphone signals due to the turbulent pressure fluctuations, which arise as the microphones are exposed to the airflow in the duct. This paper is the first in a series of two regarding the problem of turbulence-induced noise originating from the airflow inside the ducts. Part I is concerned with theoretical and experimental investigations of the influence of the turbulence-induced noise on the adaptive algorithm in the ANC system. Part II is concerned with the design and the investigations of microphone installations for turbulence suppression and the results concerning the performance of an ANC system with the different microphone installations are presented. Some of the results were obtained at an acoustic laboratory according to an ISO-standard. The attenuation achieved with ANC was approximately 15-25 dB between 50-315 Hz, even for airflow speeds up to 20 m/s
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