<?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>0187-5779</journal-id>
<journal-title><![CDATA[Terra Latinoamericana]]></journal-title>
<abbrev-journal-title><![CDATA[Terra Latinoam]]></abbrev-journal-title>
<issn>0187-5779</issn>
<publisher>
<publisher-name><![CDATA[Sociedad Mexicana de la Ciencia del Suelo A.C.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0187-57792015000200119</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Desarrollo de un penetrómetro integrado con tecnología GPS-RTK para la generación de mapas de resistencia a la penetración del suelo]]></article-title>
<article-title xml:lang="en"><![CDATA[Development of a soil penetrometer integrated with RTK-GPS technology for generating soil resistance penetration maps]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Campos Magaña]]></surname>
<given-names><![CDATA[Santos Gabriel]]></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[Cadena Zapata]]></surname>
<given-names><![CDATA[Martín]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Reynolds Chávez]]></surname>
<given-names><![CDATA[Marco Antonio]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Cuervo Piña]]></surname>
<given-names><![CDATA[Neftali]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Ramírez Fuentes]]></surname>
<given-names><![CDATA[Gabriela]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Autónoma Agraria Antonio Narro División de Ingeniería ]]></institution>
<addr-line><![CDATA[Saltillo Coahuila]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af2">
<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>06</month>
<year>2015</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>06</month>
<year>2015</year>
</pub-date>
<volume>33</volume>
<numero>2</numero>
<fpage>119</fpage>
<lpage>128</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0187-57792015000200119&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0187-57792015000200119&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0187-57792015000200119&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen: La agricultura de precisión requiere información precisa acerca de las propiedades del suelo para optimizar la aplicación de insumos y satisfacer necesidades específicas de los cultivos. En particular, la resistencia a la penetración (RP) que es un factor que mide la compactación del suelo, la cual limita el crecimiento de las raíces y el rendimiento del cultivo, lo cual requiere ubicar y cuantificar el valor de RP. El presente trabajo describe el desarrollo de un penetrómetro integrado con dos sensores (resistencia y profundidad) aplicados junto con tecnología de Posicionamiento Cinemátio en Tiempo Real-Sistema de Posicionamiento Global para Agricultura (RTK-AgGPS) para la generación de mapas de diagnóstico de capas compactadas. El primer sensor fue desarrollado para la medición de la RP utilizando un transductor de anillo simple con capacidad de hasta 9 MPa, con una sensibilidad de 13.5 Nm V-1 y un coeficiente de correlación de 99.6% entre la fuerza aplicada y el voltaje de salida. El segundo sensor, se adecuó para determinar la profundidad de RP con un desplazamiento de trabajo máximo de 0.60 m, con una sensibilidad de 258.5 mm V-1 y un coeficiente de correlación de 100% entre la profundidad de penetración y voltaje de salida. Para la evaluación en campo, se construyó un carro porta-sensores acoplado al enganche del tractor para el accionamiento del actuador hidráulico del penetrómetro. Se realizó un muestreo sistemático de 30 puntos utilizando la tecnología RTK-GPS obteniendo los valores y localización geo referenciada de RP con una precisión de 0.025 m en una profundidad de trabajo hasta de 0.40 m, esto permitió la generación de mapas de diagnóstico de la RP empleando un Sistema de Información Geográfica para tres profundidades diferentes de 0.20, 0.30 y 0.40 m.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract: Precision agriculture requires accurate information about soil properties to optimize the input supply and to satisfy a particular crop need. In particular, resistance to penetration (RP) is a factor that measures soil compaction, which limits the growth of roots and crop yield, so it is important to determine its magnitude and location. This paper describes the development of a system for measuring and monitoring physical soil properties, specifically an integrated penetrometer with two sensors (resistance and depth) connected to Real Time Kinematics-Geo Positional System for Agriculture (RTK-AgGPS) technology in order to construct soil compacted layers diagnostic maps. The first sensor was developed for RP measurement using a ring transducer with a capacity of up to 9 MPa, a sensitivity of 13.15 Nm V-1 and a correlation coefficient of 99.6% between the applied force and the output voltage. The second sensor was developed to determine with high accuracy the working depth of RP with a maximum displacement of 0.60 m, a sensitivity of 258.5 mm V-1 and a correlation coefficient of 100% between the penetration depth and the voltage output. For field evaluation, the portable sensors carriage prototype was attached to the tractor three-point hitch; the penetrometer is driven by a hydraulic actuator. Systematic sampling with 30 points was performed using RTK-GPS technology to obtain RP values and location with an accuracy of 0.025 m in a working depth range of up to 0.40 m. Three maps were generated with a GIS software for three different ranges of depths: 0.20, 0.30 and 0.40 m.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[sensores de fuerzas]]></kwd>
<kwd lng="es"><![CDATA[sensores de posición]]></kwd>
<kwd lng="es"><![CDATA[agricultura de precisión]]></kwd>
<kwd lng="en"><![CDATA[force sensor]]></kwd>
<kwd lng="en"><![CDATA[position sensor]]></kwd>
<kwd lng="en"><![CDATA[precision agriculture]]></kwd>
</kwd-group>
</article-meta>
</front><back>
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