13 research outputs found
Fault Detection and RUL Estimation for Railway HVAC Systems Using a Hybrid Model-Based Approach
Heating, ventilation, and air conditioning (HVAC) systems installed in a passenger train
carriage are critical systems, whose failures can affect people or the environment. This, together
with restrictive regulations, results in the replacement of critical components in initial stages of
degradation, as well as a lack of data on advanced stages of degradation. This paper proposes a
hybrid model-based approach (HyMA) to overcome the lack of failure data on a HVAC system
installed in a passenger train carriage. The proposed HyMA combines physics-based models with
data-driven models to deploy diagnostic and prognostic processes for a complex and critical system.
The physics-based model generates data on healthy and faulty working conditions; the faults are
generated in different levels of degradation and can appear individually or together. A fusion of
synthetic data and measured data is used to train, validate, and test the proposed hybrid model
(HyM) for fault detection and diagnostics (FDD) of the HVAC system. The model obtains an accuracy
of 92.60%. In addition, the physics-based model generates run-to-failure data for the HVAC air
filter to develop a remaining useful life (RUL) prediction model, the RUL estimations performed
obtained an accuracy in the range of 95.21–97.80% Both models obtain a remarkable accuracy. The
development presented will result in a tool which provides relevant information on the health state
of the HVAC system, extends its useful life, reduces its life cycle cost, and improves its reliability and
availability; thus enhancing the sustainability of the system.Research was funded by the Basque Government, through ELKARTEK (ref. KK-2020/00049) funding grant
Quantile regression forests-based modeling and environmental indicators for decision support in broiler farming
An efficient and sustainable animal production requires fine-tuning and control of all the parameters involved. But this is not a simple task. Animal farming is a complex biological system in which environmental parameters and management practices interact in a dynamic way. In addition, the typical non-linear response of biological processes implies that relationships across parameters that are critical to assure animal welfare and performance are difficult to determine. In this paper a novel decision support system based on environmental indicators and on weights, leg problems and mortality rates is proposed to address this issue. The data-driven modeling process is performed by a quantile regression forests approach that allows estimating growth, welfare and mortality parameters on the basis of environmental deviations from optimal farm conditions. Resulting models also provide confidence intervals able to deal with uncertainty. They are deployed in farm, offering an accessible tool for farmers, veterinarians and technical personnel. Experimental results involving 20 flocks of broiler meat chickens from different farms show the validity of the system, obtaining robust prediction intervals and high accuracy, namely over 81% for every model. The in-field use of the proposed approach will facilitate an efficient and animal welfare-friendly production management.This project was funded by the Spanish Ministry of Economy and Competitivity, General Directorate for Science and Technology, National Research Program ’Retos de la Sociedad’ Project #AGL2013-49173-C2-1-R P.I. Inma Estevez and #AGL2013-49173-C2-2-R. The authors wish to thank to AN and the farmers for facilitating access to their farms for data collection
On-Line Monitoring of Blind Fastener Installation Process
Blind fasteners are of special interest for aircraft construction since they allow working on joints where only one side is accessible, as is the case in many common aerospace box-type structures, such as stabilizers and flaps. This paper aims to deliver an online monitoring method for the detection of incorrect installed blind fasteners. In this type of fastener, the back side of the assembly is not accessible, so monitoring the process installation is suitable as a system to assess the formed head at the back side with no access. The solution proposed consists of an on-line monitoring system that is based on sensor signals acquired during the installation. The signals are conveniently analyzed in order to provide an evaluation outcome on how the fastener was installed. This new method will help production to decrease/eliminate time and cost-intensive inspections and fasteners over installation in structures. The decrease of the number of installed fasteners will also contribute to weight savings and will reduce the use of resources.This research is part of the BLINDFAST: INNOVATIVE BLIND FASTENER MONITORING
TECHNOLOGY FOR QUALITY CONTROL project, which has received funding from the European Union’s
Horizon 2020 research and innovation program under grant agreement 686827
Business analytics in industry 4.0: a systematic review
Recently, the term “Industry 4.0” has emerged to characterize several Information Technology and Communication (ICT) adoptions in production processes (e.g., Internet-of-Things, implementation of digital production support information technologies). Business Analytics is often used within the Industry 4.0, thus incorporating its data intelligence (e.g., statistical analysis, predictive modelling, optimization) expert system component. In this paper, we perform a Systematic Literature Review (SLR) on the usage of Business Analytics within the Industry 4.0 concept, covering a selection of 169 papers obtained from six major scientific publication sources from 2010 to March 2020. The selected papers were first classified in three major types, namely, Practical Application, Reviews and Framework Proposal. Then, we analysed with more detail the practical application studies which were further divided into three main categories of the Gartner analytical maturity model, Descriptive Analytics, Predictive Analytics and Prescriptive Analytics. In particular, we characterized the distinct analytics studies in terms of the industry application and data context used, impact (in terms of their Technology Readiness Level) and selected data modelling method. Our SLR analysis provides a mapping of how data-based Industry 4.0 expert systems are currently used, disclosing also research gaps and future research opportunities.The work of P. Cortez was supported by FCT - Fundação para a Ciência e Tecnologia within the R&D Units Project Scope: UIDB/00319/2020. We
would like to thank to the three anonymous reviewers for their helpful suggestions
Synthetic Data Generation in Hybrid Modelling of Railway HVAC System
This paper proposes a hybrid model (HyM)for a heating, ventilation and air conditioning (HVAC) system installed in a passenger train. This HyM fuses data from two sources: data taken from the real system and synthetic data generated using a physics-based model of the HVAC. The physical model of the HVAC was developed to include the sensors located in the real system and new virtual sensors reproducing the behaviour of the system while a failure mode (FM) is simulated. Statistical features are calculated from the selected signals. These features are labelled according to the related FMs and are merged with the features calculated from the data from the real system. This data fusion allows us to classify the condition indicators of the system according to the FMs. The merged features are used to train a neural network (NN), which achieves a remarkable accuracy. Accuracy is a key concern of future research on the detection and diagnosis of a multiple faults and the estimation of the remaining useful life (RUL) through prognosis. The outcome is beneficial for the proper functioning of the system and the safety of the passengers.Finanssiär: Basque Government (KK-2020/0004);ISBN för värdpublikation: 978-92-990084-6-1</p
Synthetic Data Generation in Hybrid Modelling of Railway HVAC System
This paper proposes a hybrid model (HyM)for a heating, ventilation and air conditioning (HVAC) system installed in a passenger train. This HyM fuses data from two sources: data taken from the real system and synthetic data generated using a physics-based model of the HVAC. The physical model of the HVAC was developed to include the sensors located in the real system and new virtual sensors reproducing the behaviour of the system while a failure mode (FM) is simulated. Statistical features are calculated from the selected signals. These features are labelled according to the related FMs and are merged with the features calculated from the data from the real system. This data fusion allows us to classify the condition indicators of the system according to the FMs. The merged features are used to train a neural network (NN), which achieves a remarkable accuracy. Accuracy is a key concern of future research on the detection and diagnosis of a multiple faults and the estimation of the remaining useful life (RUL) through prognosis. The outcome is beneficial for the proper functioning of the system and the safety of the passengers.Finanssiär: Basque Government (KK-2020/0004);ISBN för värdpublikation: 978-92-990084-6-1</p
MOTOR DE ANÁLISIS BASADO EN TÉCNICAS DE APRENDIZAJE AUTOMÁTICO PARA LA IDENTIFICACIÓN DE VARIABLES CRÍTICAS EN PROCESOS MULTIETAPA: APLICACIÓN A LA INSTALACIÓN DE REMACHES CIEGOS
Quality control in manufacturing is a recurrent topic as the ultimate goals are to produce high quality products with less cost. Mostly, the problems related to manufacturing processes are addressed focusing on the process itself putting aside other operations that belong to the part’s history. This research work presents a Machine Learning-based analysis engine for non-expert users which identifies relationships among variables throughout the manufacturing line. The developed tool was used to analyze the installation of blind fasteners in aeronautical structures, with the aim of identifying critical variables for the quality of the installed fastener, throughout the fastening and drilling stages. The results provide evidence that drilling stage affects to the fastening, especially to the formed head’s diameter. Also, the most critical phase in fastening, which is when the plastic deformation occurs, was identified. The results also revealed that the chosen process parameters, thickness of the plate and the faster type influence on the quality of the installed fastener.This project has received funding from the European Union’s 2020 research and innovation program under grant agreements No 686827 and No 723698