基于Autodesk平台的三维工程路线建构及精度研究

3D Engineering Route Construction Based on Autodesk Platform and Its Accuracy Analysis

为探究三维工程路线在Revit建模空间中的生成原理,分析不同建模方法所生成路线数据的精度问题,以复杂设计线路中心线为研究对象,采用确定性与随机性精度验证方法,结合Autodesk平台中Civil 3D、Dynamo软件辅助对Revit空间曲线建构进行研究,研究结果表明:1)Revit在二维多段线升维过程中,系统自动将多段线转换为三次(4阶)、权重为1的NURBS空间曲线,实现相邻单位多段线首尾过渡平顺。2)B-Cad法精度误差变化幅度最大,x方向达到15 mm,B-Cad与C-S法在z方向受设计纵断面圆曲线影响误差区间较为集中。3)采用加密步距的逐点拟合法进行拟合,对Revit空间曲线建构有较好的表现,建模精度能满足实际工程需求,为后续建模人员在Revit中生成各专业精细模型及其拓展应用奠定基础。

Herein,the central line of a complex design route is considered as a case study to investigate the generation principle of the three-dimensional(3D)engineering route in the Revit modeling space and analyze the accuracy of route data generated using different modeling methods.Deterministic and random accuracy verification methods are adopted to study the construction of the Revit space curve based on Civil 3D and Dynamo software in the Autodesk platform.The following research results are obtained.(1)In the process of upgrading the two-dimensional polyline of Revit,the system automatically converts the polyline to a cubic(4th order)space curve with a weight of one nonuniform rational B-spline,thus realizing a smooth transition between adjacent unit polylines.(2)The B-CAD method exhibits the largest range of accuracy errors,reaching 15 mm in the x direction.The error interval of the B-CAD and C-S methods affected by the circular curve of the designed longitudinal section is more concentrated in the z direction.(3)The point-by-point fitting method with encrypted steps is used for fitting,achieving good performance in the construction of Revit space curve.Moreover,the modeling accuracy can meet the actual engineering requirements.These results provide a reference for subsequent detailed modeling in Revit.