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Laplace moving average model for multi-axial responses in fatigue analysis of a cultivator

Kvarnstrom, Mats ; Podgorski, Krzysztof LU and Rychlik, Igor (2013) In Probabilistic Engineering Mechanics 34. p.12-25
Abstract
Modeling of loads on a vehicle through Laplace moving averages is extended to the multivariate setting and efficient methods of computing the damage indexes are discussed. Multivariate Laplace moving averages are used as statistical models of multi-axial loads represented by forces and moments measured at some locations of a cultivator. As opposed to models based on the Gaussian distribution, these models account explicitly for transients that have a common origin vibrations that can be caused by large obstacles encountered by a cultivator or a vehicle driving into potholes. The model is characterized by a low number of parameters accounting for fundamental characteristics of multivariate signals: the covariance matrix representing size of... (More)
Modeling of loads on a vehicle through Laplace moving averages is extended to the multivariate setting and efficient methods of computing the damage indexes are discussed. Multivariate Laplace moving averages are used as statistical models of multi-axial loads represented by forces and moments measured at some locations of a cultivator. As opposed to models based on the Gaussian distribution, these models account explicitly for transients that have a common origin vibrations that can be caused by large obstacles encountered by a cultivator or a vehicle driving into potholes. The model is characterized by a low number of parameters accounting for fundamental characteristics of multivariate signals: the covariance matrix representing size of loads and their mutual dependence, the excess kurtosis that in the model is related to relative size of transients, and the time scale that accounts for the vehicle speed. These parameters can be used to capture diversity of environmental conditions in which the vehicle operates. Distributions of parameter values that are specific to a given market or encountered by specific customers can be then used to describe the long term loading. The model is validated by analysis of the resulting damage index. It is shown that the parameters enter this index in a multiplicative and explicit manner and, for a given damage exponent, only the factor representing dependence on the kurtosis has to be obtained through regression approximation based on Monte Carlo simulations. An example of actual cultivator data is used to illustrate the accuracy of damage and fatigue life prediction. (C) 2013 Elsevier Ltd. All rights reserved. (Less)
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author
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organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Damage variability, Multi-axial rainflow, Laplace moving averages, Multi-axial loads
in
Probabilistic Engineering Mechanics
volume
34
pages
12 - 25
publisher
Elsevier
external identifiers
  • wos:000328305000002
  • scopus:84878834676
ISSN
0266-8920
DOI
10.1016/j.probengmech.2013.05.002
language
English
LU publication?
yes
id
33363414-8bd8-4d64-aa43-9716e87b2601 (old id 4272544)
date added to LUP
2016-04-01 11:02:54
date last changed
2022-04-04 23:43:11
@article{33363414-8bd8-4d64-aa43-9716e87b2601,
  abstract     = {{Modeling of loads on a vehicle through Laplace moving averages is extended to the multivariate setting and efficient methods of computing the damage indexes are discussed. Multivariate Laplace moving averages are used as statistical models of multi-axial loads represented by forces and moments measured at some locations of a cultivator. As opposed to models based on the Gaussian distribution, these models account explicitly for transients that have a common origin vibrations that can be caused by large obstacles encountered by a cultivator or a vehicle driving into potholes. The model is characterized by a low number of parameters accounting for fundamental characteristics of multivariate signals: the covariance matrix representing size of loads and their mutual dependence, the excess kurtosis that in the model is related to relative size of transients, and the time scale that accounts for the vehicle speed. These parameters can be used to capture diversity of environmental conditions in which the vehicle operates. Distributions of parameter values that are specific to a given market or encountered by specific customers can be then used to describe the long term loading. The model is validated by analysis of the resulting damage index. It is shown that the parameters enter this index in a multiplicative and explicit manner and, for a given damage exponent, only the factor representing dependence on the kurtosis has to be obtained through regression approximation based on Monte Carlo simulations. An example of actual cultivator data is used to illustrate the accuracy of damage and fatigue life prediction. (C) 2013 Elsevier Ltd. All rights reserved.}},
  author       = {{Kvarnstrom, Mats and Podgorski, Krzysztof and Rychlik, Igor}},
  issn         = {{0266-8920}},
  keywords     = {{Damage variability; Multi-axial rainflow; Laplace moving averages; Multi-axial loads}},
  language     = {{eng}},
  pages        = {{12--25}},
  publisher    = {{Elsevier}},
  series       = {{Probabilistic Engineering Mechanics}},
  title        = {{Laplace moving average model for multi-axial responses in fatigue analysis of a cultivator}},
  url          = {{http://dx.doi.org/10.1016/j.probengmech.2013.05.002}},
  doi          = {{10.1016/j.probengmech.2013.05.002}},
  volume       = {{34}},
  year         = {{2013}},
}