<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>2007-4026</journal-id>
<journal-title><![CDATA[Ingeniería agrícola y biosistemas]]></journal-title>
<abbrev-journal-title><![CDATA[Ing. agric. biosist.]]></abbrev-journal-title>
<issn>2007-4026</issn>
<publisher>
<publisher-name><![CDATA[Universidad Autónoma Chapingo]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S2007-40262021000200261</article-id>
<article-id pub-id-type="doi">10.5154/r.inagbi.2021.07.070</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Agricultural tractor slippage measurement system using encoders]]></article-title>
<article-title xml:lang="es"><![CDATA[Sistema de medición de patinaje de tractores agrícolas mediante codificadores]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[García-Rivera]]></surname>
<given-names><![CDATA[Gerónimo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Cadena-Zapata]]></surname>
<given-names><![CDATA[Martín]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[López-López]]></surname>
<given-names><![CDATA[Juan Antonio]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[López-López]]></surname>
<given-names><![CDATA[Gilbert Fresh]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Campo-Magaña]]></surname>
<given-names><![CDATA[Santos Gabriel]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Zermeño-González]]></surname>
<given-names><![CDATA[Alejandro]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Gutiérrez-Flores]]></surname>
<given-names><![CDATA[Hugo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Autónoma Agraria Antonio Narro  ]]></institution>
<addr-line><![CDATA[Saltillo Coahuila]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2021</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2021</year>
</pub-date>
<volume>13</volume>
<numero>2</numero>
<fpage>261</fpage>
<lpage>271</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S2007-40262021000200261&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S2007-40262021000200261&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S2007-40262021000200261&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract  Introduction:  Slippage is usually measured with a standard manual method, however, if it is required slippage information inline in extensive areas of cropland, mechanical and electronic equipment have to be developed.  Objective:  To design, assemble and evaluate (in laboratory and under field conditions) an encoder-based slippage measurement system.  Methodology:  The system was integrated and tested in the laboratory, where equations were generated to calculate the slippage. The system was installed in an agricultural tractor and its performance was evaluated on an asphalt track and working with tillage implements on various soil conditions.  Results:  The values obtained with the manual method and the encoder-based method showed very small differences. The results of field evaluation of the system are in congruence with the type of implement and with the moisture content in the soil. This indicates that the measurement of distances by the wheel turns and the calculation of the percentage of slippage are correct.  Study limitations:  The system was tested in short runs (up to 100 m). Still to be tested in at least 1 ha.  Originality:  Automated slippage measurement in extended crop areas.  Conclusions: The slippage measurement system based on encoders is reliable for automatically measuring the slippage of agricultural tractor in different field conditions.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen  Introducción:  Generalmente, el patinaje de los tractores se mide con un método manual estándar; sin embargo, si se requiere información del patinaje en línea en áreas extensas de cultivo es necesario desarrollar equipos mecánicos y electrónicos.  Objetivo:  Diseñar, montar y evaluar (en laboratorio y campo) un sistema de medición del patinaje basado en codificadores.  Metodología:  El sistema se integró y probó en laboratorio, donde se generaron ecuaciones para calcular el patinaje. El sistema se instaló en un tractor agrícola y su rendimiento se evaluó en una pista de asfalto y con implementos de labranza en diversas condiciones de suelo.  Resultados:  Los valores obtenidos con el método manual y el basado en codificadores presentaron diferencias muy pequeñas. Los resultados de la evaluación en campo son congruentes con el tipo de implemento y el contenido de humedad del suelo, lo cual indica que la medición de distancias por giros de la rueda y el cálculo del porcentaje de patinaje son correctos.  Limitaciones del estudio:  El sistema se probó en recorridos cortos, aún se debe evaluar en al menos 1 ha.  Originalidad:  Medición del patinaje automatizado en áreas extensas de cultivo.  Conclusiones: El sistema planteado es adecuado para medir automáticamente el patinaje de un tractor agrícola en diferentes condiciones de campo.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[traction]]></kwd>
<kwd lng="en"><![CDATA[tillage]]></kwd>
<kwd lng="en"><![CDATA[automation]]></kwd>
<kwd lng="en"><![CDATA[soil moisture]]></kwd>
<kwd lng="es"><![CDATA[tracción]]></kwd>
<kwd lng="es"><![CDATA[labranza]]></kwd>
<kwd lng="es"><![CDATA[automatización]]></kwd>
<kwd lng="es"><![CDATA[humedad del suelo]]></kwd>
</kwd-group>
</article-meta>
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<article-title xml:lang=""><![CDATA[Effect of plowing conditions on the tractor wheel slippage and fuel consumption in sandy soil]]></article-title>
<source><![CDATA[International Journal of ChemTech Research]]></source>
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<volume>8</volume>
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