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      <title>Orientation effect</title>
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      <div class="title_topic2" id="xps10_pagetitle">Orientation effect</div>
      <hr noshade="true">
      <p class="para_topic">The orientation effect examples demonstrate the effects that orientation has on the variation calculated by Tolerance Stackup Validation.</p>
      <div class="title_division">Case 1</div>
      <p class="para_division">This case is a simple block with one tolerance, as shown in the figure below:</p>
      <ol type="1" start="1">
         <li>
            <p class="para_item">The left side of the block is considered a datum (Datum A), and the right side has a directed dimension of 2.0+/-0.01. The origin of this dimension is Datum A.</p>
         </li>
      </ol>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/qs_orient_case1.gif"></p>
      </div>
      <div class="title_figure">Block with one tolerance</div>
      <p class="para_division">After defining a measurement between the left and right faces (using the default points in each face's center), and running a Tolerance Stackup Validation analysis, this is the output in the Information window:</p>
      <p align="center"><img align="bottom" src="graphics/qs_orient1_info.gif"></p>
      <div class="title_division">Case 2</div>
      <p class="para_division">Case 2 is the same example as Case 1, except:</p>
      <ul>
         <li>
            <p class="para_item">Full Feature Orientation (a Tolerance Stackup Validation preference) is turned OFF</p>
         </li>
         <li>
            <p class="para_item">An angular measurement between the left and right faces is defined, in order to see the effects of orientation.</p>
         </li>
      </ul>
      <p class="para_division">After running a Tolerance Stackup Validation analysis, these are the results:</p>
      <p align="center"><img align="bottom" src="graphics/qs_orient2_pts.gif"></p>
      <p class="para_division">As you can see in the figure above, in this case the calculated angular variation is zero. This is because <b class="uiTerm">Full Feature Orientation</b> was not selected, meaning that there was no control of the &quot;implicit orientation&quot; of the feature. Therefore, during the Tolerance Stackup Validation analysis, the toleranced face moved its location according to the directed dimension, but not its orientation.
      </p>
      <div class="title_division">Case 3</div>
      <p class="para_division">Case 3 is like Case 2, except that <b class="uiTerm">Full Feature Orientation</b> is selected.
      </p>
      <p class="para_division">After running a Tolerance Stackup Validation analysis, these are the results:</p>
      <p align="center"><img align="bottom" src="graphics/qs_orient3_pts.gif"></p>
      <p class="para_division">The output in the Information window is:</p>
      <p align="center"><img align="bottom" src="graphics/qs_orient3_info.gif"></p>
      <p class="para_division">In this case, the variation is equal to:</p>
      <p class="para_division">Inv tangent (0.2/2.0) = 0.5730</p>
      <p class="para_division">The angular measurement in this case has variation (unlike Case 2), because in Case 3 the toleranced face moves its orientation as well as its location. During the analysis, the plane of the toleranced face assumes all possible locations between the tolerance band of 1.99 and 2.01. But the plane is also allowed to assume all the possible orientations within that band.</p>
      <div class="title_division">Case 4</div>
      <p class="para_division">In Case 4, an orientation tolerance is clearly specified:</p>
      <ul>
         <li>
            <p class="para_item">The left side of the block is considered a datum (Datum A). The opposite face, the right face, has a directed dimension of 2.0+/-0.01. The origin of this dimension is Datum A.</p>
         </li>
         <li>
            <p class="para_item">In addition, a parallelism tolerance controls the orientation of the plane, with respect to Datum A.</p>
         </li>
      </ul>
      <div class="figure">
         <p align="center"><img align="bottom" src="graphics/qs_orient_case4.gif"></p>
      </div>
      <div class="title_figure">Block with parallelism tolerance and directed dimension</div>
      <p class="para_division">To defining a linear measurement and an angular measurement between the two faces, in order to find the linear and angular variation, and running a Tolerance Stackup Validation analysis, these are the results:</p>
      <p align="center"><img align="bottom" src="graphics/qs_orient4_pts.gif"></p>
      <p class="para_division">The results in the Information window are:</p>
      <p align="center"><img align="bottom" src="graphics/qs_orient4_info.gif"></p>
      <p class="para_division">In this case, the linear distance between the two faces is the same as Case 1. The parallelism refinement does not have an impact on this result.</p>
      <p class="para_division">But the angle variation is now completely controlled by the orientation tolerance:</p>
      <p class="para_division">Inv tangent (0.005/2.0) = 0.1432</p>
      <p class="para_division">The <b class="uiTerm">Full Feature Orientation</b> preference does not have any effect in this case, because the orientation of the feature is completely controlled by an explicit tolerance (the parallelism tolerance). The parallelism tolerance is considered to be a refinement of the directed dimension.
      </p>
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