20 research outputs found

    An SVM-Based classifier for estimating the state of various rotating components in agro-industrial machinery with a vibration signal acquired from a single point on the machine chassis

    Get PDF
    The goal of this article is to assess the feasibility of estimating the state of various rotating components in agro-industrial machinery by employing just one vibration signal acquired from a single point on the machine chassis. To do so, a Support Vector Machine (SVM)-based system is employed. Experimental tests evaluated this system by acquiring vibration data from a single point of an agricultural harvester, while varying several of its working conditions. The whole process included two major steps. Initially, the vibration data were preprocessed through twelve feature extraction algorithms, after which the Exhaustive Search method selected the most suitable features. Secondly, the SVM-based system accuracy was evaluated by using Leave-One-Out cross-validation, with the selected features as the input data. The results of this study provide evidence that (i) accurate estimation of the status of various rotating components in agro-industrial machinery is possible by processing the vibration signal acquired from a single point on the machine structure; (ii) the vibration signal can be acquired with a uniaxial accelerometer, the orientation of which does not significantly affect the classification accuracy; and, (iii) when using an SVM classifier, an 85% mean cross-validation accuracy can be reached, which only requires a maximum of seven features as its input, and no significant improvements are noted between the use of either nonlinear or linear kernels

    Signal processing techniques for agro-industrial machinery monitoring

    Get PDF
    En los últimos tiempos, las técnicas de procesado de señal han ido ganando importancia dentro de numerosas aplicaciones industriales. Estos enfoques orientados al procesado de señal están abriendo nuevas perspectivas en muchas áreas del ámbito agro-industrial, destacando entre ellas la monitorización de maquinaria. El principal objetivo de esta tesis es el diseño, implementación y evaluación de esquemas de procesado de señal específicos que permitan la monitorización de equipamiento agro-industrial en tres sentidos: mantenimiento predictivo, seguimiento de vehículos y equipos de medida. Las técnicas propuestas en esta tesis contribuyen al estado del arte, expandiendo o extendiendo técnicas existentes, e incluso proponiendo esquemas completamente novedosos. La metodología seguida a lo largo de esta tesis, con objeto de alcanzar los objetivos marcados, se puede dividir en cinco etapas: revisión del estado del arte, formulación de hipótesis, desarrollo y evaluación, análisis de resultados y publicación de resultados. En esta tesis se han abordado tres problemas agro-industriales diferentes: mantenimiento predictivo de una cosechadora agrícola, seguimiento cinemático de un vehículo y monitorización del flujo a través de cada una de las boquillas en un pulverizador agrícola. Tres características principales de los métodos propuestos destacan sobre el resto. La primera es que todos los métodos satisfacen los objetivos con una precisión suficiente. La segunda característica es que todos los métodos propuestos conducen a sistemas que son asequibles y baratos. La última característica es la optimización de los métodos, que conduce a menores necesidades computacionales en comparación con otros enfoques existentes. Esta última propiedad hace que estos métodos puedan emplearse en aplicaciones con requisitos de tiempo real. Los resultados obtenidos en esta tesis ofrecen muestras de la capacidad de monitorizar maquinaria agro-industrial ofrecida por los métodos de procesado de señal. Hay dos conclusiones principales que se puede extraer de estos resultados. La primera es que las técnicas de procesado de señal pueden obtener información útil relativa a los problemas agro-industriales abordados. La segunda conclusión es que las soluciones propuestas tienden a proporcionar mayor precisión, mejor relación efectividad-coste y son más fáciles de desplegar, en comparación con otras alternativas existentes.Departamento de Teoría de la Señal y Comunicaciones e Ingeniería TelemáticaDoctorado en Tecnologías de la Información y las Telecomunicacione

    Application of composite spectrum in agricultural machines

    Get PDF
    Producción CientíficaComposite spectrum (CS) is a data-fusion technique that reduces the number of spectra to be analyzed, simplifying the analysis process for machine monitoring and fault detection. In this work, vibration signals from five components of a combine harvester (thresher, chopper, straw walkers, sieve box, and engine) are obtained by placing four accelerometers along the combine-harvester chassis in non-optimal locations. Four individual spectra (one from each accelerometer) and three CS (non-coherent, coherent and poly-coherent spectra) from 18 cases are analyzed. The different cases result from the combination of three working conditions of the components—deactivated (off), balanced (healthy), and unbalanced (faulty)—and two speeds—idle and maximum revolutions per minute (RPM). The results showed that (i) the peaks can be identified in the four individual spectra that correspond to the rotational speeds of the five components in the analysis; (ii) the three formulations of the CS retain the relevant information from the individual spectra, thereby reducing the number of spectra required for monitoring and detecting rotating unbalances within a combine harvester; and, (iii) data noise reduction is observed in coherent and poly-coherent CS with respect to the non-coherent CS and the individual spectra. This study demonstrates that the rotating unbalances of various components within agricultural machines, can be detected with a reduced number of accelerometers located in non-optimal positions, and that it is feasible to simplify the monitoring with CS. Overall, the coherent CS may be the best composite spectra formulation in order to monitor and detect rotating unbalances in agricultural machines

    A hybrid of convolutional neural network and long short-term memory network approach to predictive maintenance

    Get PDF
    Predictive maintenance (PdM) is a successful strategy used to reduce cost by minimizing the breakdown stoppages and production loss. The massive amount of data that results from the integration between the physical and digital systems of the production process makes it possible for deep learning (DL) algorithms to be applied and utilized for fault prediction and diagnosis. This paper presents a hybrid convolutional neural network based and long short-term memory network (CNN-LSTM) approach to a predictive maintenance problem. The proposed CNN-LSTM approach enhances the predictive accuracy and also reduces the complexity of the model. To evaluate the proposed model, two comparisons with regular LSTM and gradient boosting decision tree (GBDT) methods using a freely available dataset have been made. The PdM model based on CNN-LSTM method demonstrates better prediction accuracy compared to the regular LSTM, where the average F-Score increases form 93.34% in the case of regular LSTM to 97.48% for the proposed CNN-LSTM. Compared to the related works the proposed hybrid CNN-LSTM PdM approach achieved better results in term of accuracy

    Using Machine Learning for Analysis a Database Outdoor Monitoring of Photovoltaic System

    Get PDF
    : In this paper we propose a new method for analyzing the performance of photovoltaic system using classification, the monitoring of photovoltaic module (150 W) was controlled and analyzed, the system was deployed in Algiers over a long period (80 days), one of the most important difficulties faced by researchers is collecting and analyzing the results of monitoring for a long period, so in this paper we proposed a method for analyzing results by classification using SVM Classifier. More specifically, we regrouping a data variable to multiclass for according and analyzing using SVM. We have presented thoroughly all the calculation steps. Based on the application of artificial intelligence (classification), recorded data, the power output for a given solar panels technology, types and small or large stations under any seasons can be analyzed and treated easily. The several measurements in our laboratory was investigated based on data acquisition (Keysight 34972A).The system collects the measurements from the various sensors. The measurement system was taken the data between 05h00 to 21h00 with irradiation of 50 W/m2 which is starting point, however in 0 to 50 W/m2 the system cannot detect any photovoltaic effect. Results predict that the performance ratio (PR) from a Poly-crystalline panel was around 85.28 % for a different season’s exposure and 727 point analyzes at irradiation of 850-950 W/m2 in same time 14h00-15h00 . The temperature of solar panel are also calculated and compared in different irradiation and time

    Using Machine Learning for Analysis a Database Outdoor Monitoring of Photovoltaic System

    Get PDF
    : In this paper we propose a new method for analyzing the performance of photovoltaic system using classification, the monitoring of photovoltaic module (150 W) was controlled and analyzed, the system was deployed in Algiers over a long period (80 days), one of the most important difficulties faced by researchers is collecting and analyzing the results of monitoring for a long period, so in this paper we proposed a method for analyzing results by classification using SVM Classifier. More specifically, we regrouping a data variable to multiclass for according and analyzing using SVM. We have presented thoroughly all the calculation steps. Based on the application of artificial intelligence (classification), recorded data, the power output for a given solar panels technology, types and small or large stations under any seasons can be analyzed and treated easily. The several measurements in our laboratory was investigated based on data acquisition (Keysight 34972A).The system collects the measurements from the various sensors. The measurement system was taken the data between 05h00 to 21h00 with irradiation of 50 W/m2 which is starting point, however in 0 to 50 W/m2 the system cannot detect any photovoltaic effect. Results predict that the performance ratio (PR) from a Poly-crystalline panel was around 85.28 % for a different season’s exposure and 727 point analyzes at irradiation of 850-950 W/m2 in same time 14h00-15h00 . The temperature of solar panel are also calculated and compared in different irradiation and time

    Artificial neural networks applied to the resolution of regression and classification multivariate analysis problems in the agricultural and the industrial fields

    Get PDF
    El principal objetivo de esta tesis es diseñar, implementar y evaluar modelos específicos basados en Redes Neuronales Artificiales (RNAs) para procesos agrícolas e industriales. Estos modelos considerarán un conjunto de variables diferente a los utilizados en la literatura científica, minimizarán el conocimiento previo incluido en su diseño y optimizarán su desempeño en términos de tiempo de procesado y de capacidad de cómputo. La metodología propuesta en esta tesis se aplica a cinco procesos agrícolas e industriales: el proceso de curado de tabaco, el proceso de secado del pasto varilla (Panicum virgatum), el mantenimiento predictivo de una máquina, la evaluación de piezas de acero en una línea de producción y la detección temprana de enfermedades en plantas. Los resultados obtenidos sugieren la idoneidad de las RNAs para resolver problemas multivariable de clasificación y regresión tanto en problemas de ámbito agrícola o industrial como en problemas similares de otros ámbitos.Departamento de Teoría de la Señal y Comunicaciones e Ingeniería Telemátic

    State of the art and trends in the monitoring, detection and diagnosis of failures in electric induction motors

    Get PDF
    Producción CientíficaDespite the complex mathematical models and physical phenomena on which it is based, the simplicity of its construction, its affordability, the versatility of its applications and the relative ease of its control have made the electric induction motor an essential element in a considerable number of processes at the industrial and domestic levels, in which it converts electrical energy into mechanical energy. The importance of this type of machine for the continuity of operation, mainly in industry, is such that, in addition to being an important part of the study programs of careers related to this branch of electrical engineering, a large number of investigations into monitoring, detecting and quickly diagnosing its incipient faults due to a variety of factors have been conducted. This bibliographic research aims to analyze the conceptual aspects of the first discoveries that served as the basis for the invention of the induction motor, ranging from the development of the Fourier series, the Fourier transform mathematical formula in its different forms and the measurement, treatment and analysis of signals to techniques based on artificial intelligence and soft computing. This research also includes topics of interest such as fault types and their classification according to the engine, software and hardware parts used and modern approaches or maintenance strategies

    Use an artificial intelligence method (Machine Learning) for analysis of the performance of photovoltaic systems

    Get PDF
    The performance of a photovoltaic system depends on several parameters such as temperature, clouds, and the season, which makes the study of PV performance from monitoring databases very complex given the size of the information and the complexity of the phenomena involved. This article applies an artificial intelligence (AI) method based on machine learning (ML). For more efficient analysis, the Support Vector Machine (SVM) is used to simplify and optimize the processing of these data for the study of the performance of PV systems. More precisely, we group a multi-class data variable according to the needs of the analysis using SVMs. In this article, we present all the stages of data processing based on the application of artificial intelligence (AI). We present as an example the results obtained in the study of the performance of a 150W monocrystalline photovoltaic (PV) module after one year of monitoring
    corecore