该页全部中文内容仅供20252453-T-424 项目组内部使用

20252453-T-424 项目

4.2.2.1.2 布洛斯过渡段(Bloss Transition Segment)

布洛斯过渡段是五次螺旋线的一种特殊情况,其曲率变化率为三次函数,并且各项取决于从拐点开始测量的长度 L。参数值定义为偏角,即方位角 Θ。

仅填充三次项和二次项,并使用以下值: 三次项 = L/³√2 二次项 = L/√3

下图展示了应用此概念时使用的通用类和关系。

<a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcCurveSegment.htm'>IfcCurveSegment</a> IfcCurveSegment      LayerAssignment [0:1]      StyledByItem [0:1] 1. Transition [1:1]      UsingCurves [1:?] 2. Placement [1:1] 3. SegmentStart [1:1] 4. SegmentLength [1:1] 5. ParentCurve [1:1] <a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcThirdOrderPolynomialSpiral.htm'>IfcThirdOrderPolynomialSpiral</a> IfcThirdOrderPolynomialSpiral      LayerAssignment [0:1]      StyledByItem [0:1] 1. Position [1:1] 2. CubicTerm [1:1] 3. QuadraticTerm [0:1] 4. LinearTerm [0:1] 5. ConstantTerm [0:1] <a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcCurveSegment.htm'>IfcCurveSegment</a>:ParentCurve1-><a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcThirdOrderPolynomialSpiral.htm'>IfcThirdOrderPolynomialSpiral</a>:IfcThirdOrderPolynomialSpiral0 IfcLengthMeasure_0 IfcLengthMeasure <a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcThirdOrderPolynomialSpiral.htm'>IfcThirdOrderPolynomialSpiral</a>:QubicTerm1->IfcLengthMeasure_0:IfcLengthMeasure0 IfcLengthMeasure_1 IfcLengthMeasure <a href='/IFC/RELEASE/IFC4x3/HTML/lexical/IfcThirdOrderPolynomialSpiral.htm'>IfcThirdOrderPolynomialSpiral</a>:QuadraticTerm1->IfcLengthMeasure_1:IfcLengthMeasure0
Figure 4.2.2.1.2.A