基准目标是零件在加工和检验过程中与夹具或测具相接触的有规定的大小和位置的点、线或面。这些特定的点、线或面按照六点定位的原理建立三基面体系。 基准目标系统最初应用于以粗糙表面定位的零件上。但目前在国外,基准目标已在铸件 The baseline target is a point, line or area of ​​a specified size and position where the part is in contact with the fixture or fixture during machining and inspection. These specific points, lines or surfaces are built in a three-point system according to the principle of six-point positioning. The baseline target system was originally applied to parts with a rough surface. However, at present, the benchmark has been casting