Collaborative Research: Quantitative Roundness Design and Quality Assurance for Ultra-Precision Assemblies with Significant Error-Scaling Problems

该项目的目标是揭示在设计和制造中超精密应用的误差比例问题的新的和基本的见解，并回答长期以来关于圆度形位公差的定量设计的问题。当关键特征的大小接近制造过程中实现的重复性的大小时，当精度的不确定度变得不可接受时，这种误差比例问题就会出现。建立了一项合作，以开发一种量化技术，以设计和实现制造精密圆形部件和组件(如喷油器和主轴)的质量保证。虽然工程师现在在分配适当的尺寸公差方面得到了更好的培训，但目前还没有一种定量的方法来分配形位公差，如圆度。此外，对制造小规模(介观、微米和纳米)器件至关重要的误差缩放问题。因此，质量保证指数的基本定义将通过一种新的概率分析重新考虑，该分析考虑了显著误差比例问题区域中的截断和倾斜分布。然后，这些改进的指数可以被纳入到成功的质量保证方法中，如全面质量管理和六西格玛。圆度问题具有重大的经济和社会影响。低排放柴油机的发展需要清洁柴油、电控燃油喷射和高喷射压力。要实现高喷射压力(超过30 ksi)，需要非常精确地控制喷嘴和喷油器柱塞之间的配合条件，而这又严重取决于柱塞和喷嘴孔的圆度。所提出的圆度技术对于成像、电信、光刻和许多其他领域的微型化技术也是至关重要的。

The objective of the project is to reveal new and fundamental insights into the error-scaling problem for ultra-precision applications in design and manufacturing and answer long-standing questions about quantitative design of geometric tolerances in roundness. This error-scaling problem arises when the uncertainty of precision becomes unacceptably large as the size of the critical features approaches in magnitude the size of the repeatability achieved during manufacturing. A collaboration is formed to develop a quantitative technology for designing and achieving quality assurance for manufacturing precision round components and assemblies, such as fuel injectors and spindles. Although engineers are now better trained in assigning proper size tolerance, at present there does not exist a quantitative methodology for assigning geometric tolerances such as roundness. Furthermore, the error-scaling problem that is critical to the manufacture of small scale (meso, micro, and nano) devices. As a result, fundamental definitions of quality assurance indices will be revisited via a new probability analysis considering truncated and skewed distributions in the region of significant error-scaling problems. These improved indices can then be incorporated into successful quality assurance approaches such as TQM and Six-Sigma. Roundness issues have great economic and social impacts. The development of low-emission diesel engines requires clean diesel fuel, electronically controlled fuel injection, and high injection pressure. Achieving a high injection pressure (over 30 ksi) requires a very precise control of fit conditions between the nozzle and the injector plunger, which in turn depends critically on the roundness of the plunger and nozzle bore. The proposed roundness technology is also critical for miniaturization techniques in imaging, in telecommunication, in lithography, and in many other fields.