Abstract: To deal with the disadvantages of geometric precision expression in tolerance design process, by analyzing the precision information such as geometric deviation, tolerance domain and tolerance grade, a visualization method for dimension and geometric precision based on color perception and annotation expression was proposed. Through analysis of geometric model, precision model and 3D annotation model in assembly system, geometric precision visualization model as well as mapping relationship between precision information and color value were established. Thus the association problem on visualization model, geometric model and 3D annotation model was solved. By means of virtual environment's rendering technology, geometric precision visualization of germetric error relative to error limit was realized, and absolute geometric precision visualization reflecting tolerance grade was also realized. The perceptibility and interaction of geometric precision in virtual assembly system was improved. The related model and algorithm were realized in prototype system and verified by examples.

Key words: geometric precision, visualization, models, assembly precision, virtual assembly

摘要： 针对公差设计过程中产品几何精度信息的表达缺乏直观性和可感知性的问题，在分析几何偏差、公差域及公差等级等精度信息的基础上，提出基于标注模式和颜色感知的几何精度可视化表达方法。通过解析装配系统中的几何模型、精度模型及三维标注模型，建立几何精度的可视化模型以及精度信息与颜色值的映射关系，解决了可视化模型与几何模型、三维标注模型等的关联问题。在此基础上，借助虚拟环境相关渲染技术，实现了几何偏差或误差相对于上下偏差限的几何精度相对可视化，以及反映公差等级的几何精度绝对可视化，提高了几何精度信息在虚拟装配系统中的可感知和可交互性。相关模型和算法已在原型系统中得到实现，并通过实例进行了验证。

关键词: 几何精度, 可视化, 模型, 装配精度, 虚拟装配