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      <title>Check criteria - Self-Intersection Loop Check (G-LO-IS)</title>
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      <div class="title_topic4" id="xps10_pagetitle">Check criteria - Self-Intersection Loop Check (G-LO-IS)</div>
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               <p class="para_td"> <a class="links" href="javascript:void(0)" onclick="top.openFile('nx_analysis/vda_checker.html');return(false);">Check VDA-4955 Compliance Overview</a></p>
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               <p class="para_td"> <a class="links" href="javascript:void(0)" onclick="top.openFile('nx_analysis/vda_criteria.html');return(false);">Description of the Check Criteria</a></p>
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               <p class="para_td"> <a class="links" href="javascript:void(0)" onclick="top.openFile('nx_analysis/vda4955_check_crit_fac_topo.html');return(false);">Faces (Topology)</a></p>
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               <p class="para_td">Self-Intersection Loop Check (G-LO-IS)</p>
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               <p class="para_td">Input</p>
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               <p class="para_td">Faces, solid bodies, and sheet bodies</p>
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               <p class="para_td">Parameters</p>
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                  <li>
                     <p class="para_item">A lower limit of the self intersection distance</p>
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                  <li>
                     <p class="para_item">Spike and cut option</p>
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                  <li>
                     <p class="para_item">Spike and cut angle</p>
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               <p class="para_td">What is analyzed?</p>
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               <p class="para_td">Validates whether one or more intersection points exist in the loop within the designated accuracy that is measured by the self intersection distance tolerance.  If you turn on the spike and cut option, the checker also finds spikes and cuts along the face loop. The self-intersection loop is an existing criterion (F14) in the VDA 4955 Checker, but this checker only focuses on the external face loop.</p>
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               <p class="para_td"> <img align="bottom" src="graphics/si_loop.gif" border="0"></p>
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               <p class="para_th">Example of a Self-Intersection Loop Check</p>
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               <p class="para_td">The black curve is the original curve; the red line is the self-intersecting offset curve.</p>
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               <p class="para_td">Results Log&nbsp; Output</p>
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               <p class="para_td">G-LO-IS</p>
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                  <li>
                     <p class="para_item">Self-Intersection</p>
                  </li>
                  <li>
                     <p class="para_item">Object ID of the self intersection face</p>
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                  <li>
                     <p class="para_item">Minimum distance at self intersection points</p>
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                  <li>
                     <p class="para_item">Intersection point on edge 1</p>
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                  <li>
                     <p class="para_item">Edge owning edge curve 1</p>
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                  <li>
                     <p class="para_item">Intersection point on edge 2; only if no intersection point but point 1 and point 2 nearly touch and edges 1 and 2 are not identical</p>
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                  <li>
                     <p class="para_item">Edge owning edge curve 2 only if edges 1 and 2 are not identical</p>
                  </li>
               </ul>
               <p class="para_td">Spike and Cut</p>
               <ul>
                  <li>
                     <p class="para_item">Object ID of the face with spikes and cuts</p>
                  </li>
                  <li>
                     <p class="para_item">The value of violation angle in degrees</p>
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                  <li>
                     <p class="para_item">Spike and cut type</p>
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                  <li>
                     <p class="para_item">0 &mdash; Spike/cut with none of the qualifications below</p>
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                  <li>
                     <p class="para_item">1 &mdash; Warning. After initial widening, the spike sides become more narrow. A spike could not be clearly identified.</p>
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                  <li>
                     <p class="para_item">2 &mdash; Needle; Open distance is &lt; 0.05*length of the smaller side of the spike.</p>
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                  <li>
                     <p class="para_item">3 &mdash; Warning. Unable to determine the complete length of a side. A spike could not be clearly identified.</p>
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                  <li>
                     <p class="para_item">4 &mdash; Found more than one spike in the same point set range.</p>
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                  <li>
                     <p class="para_item">Spike point 1</p>
                  </li>
                  <li>
                     <p class="para_item">Spike point 2</p>
                  </li>
                  <li>
                     <p class="para_item">Object ID of edge arriving at spike point 1</p>
                  </li>
                  <li>
                     <p class="para_item">Object ID of edge leaving at spike point 1</p>
                  </li>
               </ul>
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