对于检具基准圆，一般会有两个定位销孔，两个沉头孔（锁螺丝）,对于PC DMIS 和RationalDMIS直接使用软件向量创建测量，面上三点一般会有一点采集孔里。软件在RationalDMIS5.5版本以后，增加了：“用户控制向量创建采样点位置”对于低版本如何实现？一般圆的测量规则如下: 1.大范围取点（避开倒角位置） 2.均匀取点 3.在同一高度上测量 4.圆所在的圆柱或者圆锥与坐标轴不平行，需要使用向量创建测量(DMIS关键字是VECBLD)，或建立合适的坐标系，解决探头补偿方向和余弦误差等问题，可以直接用默认的工作平面去测量。通常, 要测量一个两维元素比如一个圆,这个圆在一个不与任何坐标平面平行的平面内,需要一下几步:a. 测量圆所在的平面.b. 拖放这个平面到工作平面选择窗口.c. 测量平面上的圆."向量构建"方法基本上也是重复这几步,只是没有创建平面元素.它把平面测量结合到圆自参考测量中去.由以上可知，对于圆孔端面圆，可以分解测量，先测量一个平面，在测量一个圆，投影平面为圆孔上端面。建立坐标系的步骤：1.粗建坐标系2.精建坐标系拾取三个圆孔上端面，三个平面，自动测量平面，避开圆孔。测量三个基准圆孔，构造：“投影”三个圆孔分别向圆孔上端面投影。建立坐标系的步骤：1.粗建坐标系DMISMN/'Created by [山涧果子] on 星期四, 十二月 21, 2017', 4.0UNITS/MM, ANGDECWKPLAN/XYPLANPRCOMP/ONTECOMP/ONFLY/1.000000MODE/PROG, MANSNSET/APPRCH, 2.000000SNSET/RETRCT, 2.000000SNSET/DEPTH, 2.000000SNSET/SEARCH, 10.000000SNSET/CLRSRF, 0.000000RECALL/D(MCS)SNSLCT/S(ROOTSN1)GEOALG/CIRCLE, LSTSQRGEOALG/ARC, LSTSQRGEOALG/PLANE, LSTSQR$$$$MODE/MANF(CIR1) = FEAT/CIRCLE,INNER,CART, 840.000000, -550.000000, 600.000000,$ -1.000000, 0.000000, -0.000000, 10.000000$$ Empty VECBLD BlockRMEAS/CIRCLE, F(CIR1), 4, VECBLD, 3.000000, 3ENDMESF(CIR2) = FEAT/CIRCLE,INNER,CART, 840.000000, -1000.000000, 600.000000,$ -1.000000, 0.000000, -0.000000, 10.000000$$ Empty VECBLD BlockRMEAS/CIRCLE, F(CIR2), 4, VECBLD, 3.000000, 3ENDMESF(CIR3) = FEAT/CIRCLE,INNER,CART, 840.000000, -550.000000, 900.000000,$ -1.000000, 0.000000, -0.000000, 10.000000$$ Empty VECBLD BlockRMEAS/CIRCLE, F(CIR3), 4, VECBLD, 3.000000, 3ENDMESF(CIR1) = FEAT/CIRCLE,INNER,CART, 840.000000, -550.000000, 600.000000,$ -1.000000, 0.000000, -0.000000, 10.000000F(CIR2) = FEAT/CIRCLE,INNER,CART, 840.000000, -1000.000000, 600.000000,$ -1.000000, 0.000000, -0.000000, 10.000000F(CIR3) = FEAT/CIRCLE,INNER,CART, 840.000000, -550.000000, 900.000000,$ -1.000000, 0.000000, -0.000000, 10.000000DMESW/COMAND,'3PtsCRDBestfitAveErr/OFF'D(CRD1) = LOCATE/FA(CIR1), FA(CIR2), FA(CIR3)$$ Set.CAD2PCS.CADM_1$$ Set.CADViewCenter.CADM_1TEXT/OPER, '请将测头移动到安全位置！'MODE/PROG,MANSNSET/APPRCH, 2.0000SNSET/RETRCT, 2.0000SNSET/DEPTH, 2.0000SNSET/SEARCH, 10.0000SNSET/CLRSRF, 50GOTO/700.000000, -550.000000, 600.000000GOTO/810.000000, -550.000000, 600.000000F(PLN1) = FEAT/PLANE,CART, 840.000000,-550.000000,600.000000, -1.000000,$ 0.000000,-0.000000$$ Measurement points are created through nominal pointsMEAS/PLANE, F(PLN1), 3 GOTO/CART, 789.000000, -550.000000, 600.000000 GOTO/CART, 789.000000, -543.185059, 607.118408 PTMEAS/CART, 840.000000, -543.185059, 607.118408, -1.000000, -0.000000,$ -0.000000 PTMEAS/CART, 840.000000, -542.179687, 592.705933, -1.000000, -0.000000,$ -0.000000 PTMEAS/CART, 840.000000, -559.115173, 593.516418, -1.000000, -0.000000,$ -0.000000 GOTO/CART, 810.000000, -550.000000, 600.000000ENDMESF(1K) = FEAT/CIRCLE,INNER,CART, 840.000000, -550.000000, 600.000000,$ -1.000000, 0.000000, -0.000000, 10.000000$$ Measurement points are created through nominal pointsMEAS/CIRCLE, F(1K), 4 GOTO/CART, 789.000000, -550.000000, 600.000000 GOTO/CART, 789.000000, -550.000000, 602.000000 GOTO/CART, 790.000000, -550.000000, 602.000000 PTMEAS/CART, 842.000000, -550.000000, 605.000000, -0.000000, 0.000000,$ -1.000000 PTMEAS/CART, 842.000000, -555.000000, 600.000000, 0.000000, 1.000000,$ -0.000000 PTMEAS/CART, 842.000000, -550.000000, 595.000000, 0.000000, -0.000000,$ 1.000000 PTMEAS/CART, 842.000000, -545.000000, 600.000000, -0.000000, -1.000000,$ 0.000000 GOTO/CART, 790.000000, -548.000000, 600.000000ENDMESCONST/CIRCLE,F(1K),PROJCT,FA(1K),FA(PLN1)GOTO/700.000000, -550.000000, 600.000000GOTO/700.000000, -1000.000000, 600.000000GOTO/810.000000, -1000.000000, 600.000000F(PLN2) = FEAT/PLANE,CART, 840.000000, -1000.000000, 600.000000, -1.000000,$ 0.000000, -0.000000$$ Measurement points are created through nominal pointsMEAS/PLANE, F(PLN2), 3 GOTO/CART, 789.000000, -1000.000000, 600.000000 GOTO/CART, 789.000000, -992.688904, 607.151184 PTMEAS/CART, 840.000000, -992.688904, 607.151184, -1.000000, -0.000000,$ -0.000000 PTMEAS/CART, 840.000000, -991.897278, 593.769897, -1.000000, -0.000000,$ -0.000000 PTMEAS/CART, 840.000000, -1007.628723, 593.359985, -1.000000, -0.000000,$ -0.000000 GOTO/CART, 810.000000, -1000.000000, 600.000000ENDMESF(2K) = FEAT/CIRCLE,INNER,CART, 840.000000, -1000.000000, 600.000000,$ -1.000000, 0.000000, -0.000000, 10.000000$$ Measurement points are created through nominal pointsMEAS/CIRCLE, F(2K), 4 GOTO/CART, 789.000000, -1000.000000, 600.000000 GOTO/CART, 789.000000, -1000.000000, 602.000000 GOTO/CART, 790.000000, -1000.000000, 602.000000 PTMEAS/CART, 842.000000, -1000.000000, 605.000000, -0.000000, 0.000000,$ -1.000000 PTMEAS/CART, 842.000000, -1005.000000, 600.000000, 0.000000, 1.000000,$ -0.000000 PTMEAS/CART, 842.000000, -1000.000000, 595.000000, 0.000000, -0.000000,$ 1.000000 PTMEAS/CART, 842.000000, -995.000000, 600.000000, -0.000000, -1.000000,$ 0.000000 GOTO/CART, 790.000000, -998.000000, 600.000000ENDMESCONST/CIRCLE,F(2K),PROJCT,FA(2K),FA(PLN2)GOTO/700.000000, -1000.000000, 600.000000GOTO/700.000000, -550.000000, 900.000000GOTO/810.000000, -550.000000, 900.000000F(PLN3) = FEAT/PLANE,CART, 840.000000, -550.000000, 900.000000, -1.000000,$ 0.000000, -0.000000$$ Measurement points are created through nominal pointsMEAS/PLANE, F(PLN3), 3 GOTO/CART, 789.000000, -550.000000, 900.000000 GOTO/CART, 789.000000, -543.002991, 907.338196 PTMEAS/CART, 840.000000, -543.002991, 907.338196, -1.000000, -0.000000,$ -0.000000 PTMEAS/CART, 840.000000, -540.795715, 892.309204, -1.000000, -0.000000,$ -0.000000 PTMEAS/CART, 840.000000, -559.368652, 892.356567, -1.000000, -0.000000,$ -0.000000 GOTO/CART, 810.000000, -550.000000, 900.000000ENDMESF(3K) = FEAT/CIRCLE,INNER,CART, 840.000000, -550.000000, 900.000000,$ -1.000000, 0.000000, -0.000000, 10.000000$$ Measurement points are created through nominal pointsMEAS/CIRCLE, F(3K), 4 GOTO/CART, 789.000000, -550.000000, 900.000000 GOTO/CART, 789.000000, -550.000000, 902.000000 GOTO/CART, 790.000000, -550.000000, 902.000000 PTMEAS/CART, 842.000000, -550.000000, 905.000000, -0.000000, 0.000000,$ -1.000000 PTMEAS/CART, 842.000000, -555.000000, 900.000000, 0.000000, 1.000000,$ -0.000000 PTMEAS/CART, 842.000000, -550.000000, 895.000000, 0.000000, -0.000000,$ 1.000000 PTMEAS/CART, 842.000000, -545.000000, 900.000000, -0.000000, -1.000000,$ 0.000000 GOTO/CART, 790.000000, -548.000000, 900.000000ENDMESCONST/CIRCLE,F(3K),PROJCT,FA(3K),FA(PLN3)F(1K) = FEAT/CIRCLE,INNER,CART, 840.000000, -550.000000, 600.000000,$ -1.000000, -0.000000, 0.000000, 10.000000F(2K) = FEAT/CIRCLE,INNER,CART, 840.000000, -1000.000000, 600.000000,$ -1.000000, -0.000000, 0.000000, 10.000000F(3K) = FEAT/CIRCLE,INNER,CART, 840.000000, -550.000000, 900.000000,$ -1.000000, -0.000000, 0.000000, 10.000000DMESW/COMAND,'3PtsCRDBestfitAveErr/OFF'D(CRD2) = LOCATE/FA(1K), FA(2K), FA(3K)$$ Set.CAD2PCS.CADM_1$$ Set.CADViewCenter.CADM_1来源：山涧果子
