Abstract: This paper focused on the dimensional development and design of clearance for scissor door and the fender on new car model, digital mock-up (DMU) movement simulation module of CATIA and 3D deviation analysis software 3DCS are used to establish dimension simulation model, simulating motion deviation of scissor door closure and calculating the minimum clearance of the scissor door and the fender in the design-state by DMU dimensional analysis, DMU combining 3DCS static analysis and 3DCS Mechanical analysis. The results show that (4.0±1.0) mm design gap between the scissor door and the fender can not only ensures competitive dimensional design requirements but also avoids the risk of motion interference. In the end, the advantages and disadvantages and scope of application of three analytical methods are described in the paper, and the rationality of the analysis results are verified according to the physical vehicles.

Key words: Dimension chain; 3DCS; Movement clearance; DMU; Scissor door

摘要： 文章围绕新车型上剪刀门与翼子板间隙尺寸开发设计展开，利用 CATIA 软件的数字样 车技术（DMU）运动仿真模块与三维偏差分析软件 3DCS 建立仿真模型，通过 DMU 尺寸分 析、DMU 结合 3DCS 静态分析、3DCS Mechanical 运动分析三种仿真方法模拟剪刀门运动过 程的尺寸偏差，计算设计状态下剪刀门与翼子板的最小运动间隙。结果表明，剪刀门与翼子 板间隙设计值（4.0±1.0）mm 可以在保证尺寸设计精致性的同时避免运动干涉。最后，文章 对三种分析方法的优劣性与适用范围进行了总结，并且通过实车验证了理论仿真的可靠性。

关键词: 尺寸链；3DCS；运动间隙；DMU；剪刀门