SBIR-STTR Award

This Small Business Innovation Research Phase I project will perform the critical research that ultimately leads to a robust, hand-held, video-rate surface metrology system to bridge a critical existing metrology gap for precision-machined surfaces. The broader impact of this project will be to improve yield, performance, safety, and lifetime of components in a wide range of critical U.S. industries including automotive, aerospace, and medical devices. For example, minor surface imperfections on edges or in other critical areas can have a dramatic effect on performance of components such as turbine blades, cutting tools, or other high-stress elements. In the turbine industry, during maintenance inspections, wear scars or corrosion pits that can lead to catastrophic failures must be quantified to ensure only necessary repairs and replacements are performed; current inspection technologies lead to high rejection rates of good parts since lack of good quantification necessitates conservatism in part rejection. This high-precision, portable, shop-floor gage will greatly enhance quantification of such features, leading to enhanced competitiveness across multiple critical U.S. manufacturing industries that employ a wide range of processing technologies. The total available market for such an instrument is estimated to be greater than $45 million annually in the initially identified application spaces.

The intellectual merit of this project is the demonstration of a novel instantaneous whole-field optical method for measuring rough surfaces with micron resolution and centimeter field of view. Instantaneous whole-field acquisition enables high-resolution measurements to be made in environments not possible with current technology. Benefits of this technology range from increased manufacturing capability in aerospace (for example, production of turbine blades with improved efficiency), to fields such as medical imaging where motion and vibration are intrinsic. The research objectives for this program are to develop and/or demonstrate feasibility of several key components: an efficient method of generating polarization-based fringe patterns to enable instantaneous measurement, a state-of-the-art light source, compact optics capable of high-efficiency illumination and large-area imaging, and robust data processing techniques. Extensive modeling and experimentation will be combined to ensure success of each of the technical objectives. Once key components are developed, a breadboard system will be built and comprehensively tested against a variety of critical metrology goals. At the end of this Phase I effort, the anticipated outcome will be a working breadboard capable of vibration-immune, three-dimensional surface metrology with micron-level lateral and vertical resolution, applicable to a wide range of precision machined surfaces.

This Small Business Innovation Research (SBIR) Phase II project will develop and produce a robust, hand-held, video-rate three-dimensional surface metrology system with vertical and lateral resolution of several micrometers, in order to bridge a critical existing metrology gap for precision-machined surfaces. Many modern manufactured parts, such as turbine blades, drive shafts, orthopedics, and various additive manufactured components require in-situ metrology with high resolution for accurate characterization during manufacturing and/or maintenance operations. Current high-resolution surface measurement systems are slow, vibration-sensitive and laboratory-based and thus are impractical for everyday use by manufacturing technicians. Meanwhile, shop-floor inspection is often only visual, and thus qualitative rather than quantitative, leading both to rejections of acceptable components as well as potential acceptance of failing ones. The absence of high-precision, in-situ metrology has hindered manufacturers from applying real-time data analysis and closed-loop process controls that can improve yields and reduce manufacturing costs. This research program will yield a hand-held, easy-to-use, robust, and quantitative shop-floor measurement system, allowing manufacturers to improve lifetimes, performance, and yield as they rapidly assess the features under test and feed the results back to improve process control.During Phase I, a breadboard system was designed and implemented using a polarization-based fringe projection method and micropolarizer phase-mask technology to achieve vibration insensitive measurement in a compact package. This Phase II program leverages that research to design a video-rate, compact, robust and portable system for handheld surface measurements in shop-floor environments. This will first involve improvements to measurement resolution with an improved optical design and new self-calibrating measurement modes; new optical elements will lower noise artifacts caused by imperfections in the earlier design and to reduce system size. Once performance of the new design is verified, an ergonomic, compact, robust, wireless housing for the instrument must be created to enable shop-floor use; the system must handle drops of over one meter onto concrete, have useful battery life for extended field operations, be light enough to not fatigue users and have intuitive controls and feedback. A final, critically important development effort will create automated software routines for measurement, analysis, and system diagnostics to enable adoption by unskilled personnel in manufacturing environments. Lastly, extensive applications testing in the field will allow optimization of the system to handle a wide range of potential use cases and environments.