Non-Contact Pencil Probe for Advanced Manufacturing Inspection

这项提议旨在最终开发出一种高精度的微型探头，能够检测复杂几何形状的已制造零件。将采用一种新的基于激光的非接触式检测技术，该设备因其计划的形状和大小而被称为非接触式铅笔探头。光学系统分为两个子系统：照明子系统和观察子系统。将使用三角测量方法。传统的光学元件不太适合铅笔探头，因为它们的相对尺寸很大。要达到提议的目标，需要截然不同的光学技术。计划使用渐变折射率(GRIN)透镜。GRIN透镜的光学性能与传统透镜一样，但厚度恒定，折射率变化，而不是传统的折射率恒定，厚度变化。GRIN透镜可以获得小直径的透镜。该装置的照明和观察光学系统将由狭长的GRIN棒透镜组成。将使用激光二极管作为照明源，探测器阵列或侧向效应光电二极管作为探测器。第一阶段的研究计划是设计和制造一个原型装置，并通过实验证明非接触式铅笔探头的可行性。计划进行第二阶段，对铅笔探头进行修改和优化，以满足最大数量的检查需求。如果这项研究成功，第三阶段将获得资金将该设备商业化。铅笔探头应该会增加检查能力，并导致质量的提高。应用将用于检查复杂的几何形状，如仿形涡轮叶片，详细描述活塞环凹槽，查看隐藏在外部视图中的零件，以及查看孔内的螺纹。

This proposal is aimed at the ultimate development of a high accuracy, miniature probe capable of inspecting manufactured parts with complex geometries. A novel laser based, non-contact inspection technique will be employed and the device is called a non-contact pencil probe because of its planned shape and size. The optical system is divided into two subsystems; these are illumination and viewing subsystems. A triangulation method will be used. Conventional optical components are not well suited for the pencil probe because of their large relative size. Radically different optical techniques are required to reach the proposed goals. The use of graded index (GRIN) lenses is planned. The GRIN lenses behave optically like conventional lenses but have constant thickness with varied index of refraction instead of the conventional constant index of refraction with varied thickness. GRIN lenses can be obtained in small diameter sizes. The illumination and viewing optics of the proposed device will consist of long narrow GRIN rod lenses. A laser diode will be used as the illumination source and a detector array or a lateral effect photodiode as the detector. The Phase I research plan is to design and build a prototype device and experimentally demonstrate the feasibility of the non-contact pencil probe. A Phase II is planned which will modify and optimize the pencil probe to meet the largest number of inspection needs. If this research is successful, Phase III will obtain funding to commercialize this device. The pencil probe should increase inspection capabilities and lead to improved quality. Application would be to inspection of complex geometries, such as profiling turbine blades, detailing piston ring grooves, viewing parts hidden from external view, and looking at threads within a hole.