Metrology automation for the aerospace industry

For many years computer-aided design/computer-aided manufacturing (CAD/CAM) has been driving the future of manufacturing. With these high value engineering tools, designing and manufacturing have improved dramatically. Advances in CAD systems have coincided with a shift to model-based design (MBD) in the aerospace industry, driven by supply chain diversification and the need for consistent standards across all subcontractors responsible for manufacturing components.

Digital metrology and inspection are also advancing at a similar pace. Automation of coordinate measuring machine (CMM) programming is being revolutionized using CAD-related features and functionality. These advancements are driving automation in aerospace CMM part programming.

Developments impacting measurement

In the past, CMM programmers relied on customer drawings for part programming, which is laborious, time consuming, interpretive, and knowledge driven. While still used today, it requires high skill and is prone to errors. CAD, however, is driving the creation of part programs, but it comes with its own set of hurdles such as: file format, conversions, translations vs. native file support, and cost of ownership/maintenance. The digitization of the CAD industry and the advent of MBD is changing manufacturing.

The other major development is product and manufacturing information (PMI), a system CAD-based annotation of the model that’s creating a paradigm shift in CMM programming. In the model, geometric dimensions and tolerances (GD&T) are added to the model features. PMI has some additional properties such as PMI representation (a.k.a. semantic PMI) and PMI presentation (a.k.a. graphical PMI) to assist in usage and readability. This information set can be passed downstream for use in CAM and metrology system programming. PMI also provides associative tolerancing requiring designers to incorporate proper usage of GD&T.

In aerospace, CATIA and Solid Works are predominant CAD systems. Both are flexible and can incorporate PMI data into the models. By using PMI, CMM manufactures’ software can generate automatic measurement part programs and create detailed reports, but there remains a gap in getting the measurement data back to overlay it on the model. Until recently, there was no truly standard format. Each CAD company had their own way to push or accept data. Now, however, the quality information framework (QIF) standard has become an ISO standard. Aircraft manufacturers are looking to it as an industry standard that works across all platforms, including when used with independent file formats which smaller vendors can read with lower-end software.

The result is traceability of any airplane part – where it was made, who designed it, who measured it, where the measurement data resides, the serial number, and more – throughout its product life cycle. The aerospace industry has been driving this standardization and traceability that’s become even more prevalent due to the increase in subcontractors making parts. Also, the National Institute of Technologies (NIST) can’t be overlooked when talking about standards.

Conforming to standards

NIST, in conjunction with industry partners, has provided a validation and conformance test project. This allows industry free use to better explore and test their internal systems for PMI optimization and implementation.

NIST is also testing the generation of derivative Standards for the Exchange of Product Data (STEP). This is important for the industry as STEP AP 242 is a combination of AP 203 and AP 214; STEP AP 242 incorporates PMI integrated within the models. The commonality of STEP allows CAD format neutrality without the customer needs for costly support of multiple vendor CAD systems. Also, it provides a benefit to some as proprietary CAD information doesn’t need to be shared.

As CAD-PMI continues to evolve, other tools are being incorporated into the environment. One such tool is QIF, a unified XML framework standard for quality systems. Developed by the Digital Quality Standards Consortium, it supports the reuse of quality related data throughout the product life cycle. With the most recent release, QIF 3.0, it’s been adopted as ISO standard 23952:2020. This is an important milestone for customers as worldwide adoption of this framework is now ongoing.

Metrology suppliers are excited to create new methods and software to support the full power of automation, especially in the aerospace industry. CMM parts programming can be a significant expense with the need for CAD, metrology, GD&T, and in some cases engineering knowledge. By using a metrology software system built for CAD with PMI interpretation, a system such as Mitutoyo’s MiCAT planner provides customers the tools to create advanced part programs with associated tolerance information. This methodology simplifies program generation and provides common rules sets, advanced collision detection, and 3D simulation for operator visualization. With the incorporation of QIF data, results are captured allowing real-time updated annotations to CAD models for analysis.

This article captures some of the ways CAD is driving automation within metrology programming for the aerospace industry while the References link to more information on developing internal measurement processes toward automation. The ongoing development of MBD, PMI, and QIF is not only driving the future of aerospace manufacturing, but also driving the incorporation of tools for metrology automation.

Mitutoyo America

About the author: Michael Creney is vice president of product management for Mitutoyo America. He can be reached at michael.creney@mitutoyo.com.

References

National Institute of Technologies (NIST) Product and manufacturing information (PMI)

Digital Metrology Standards Consortium (DSMC) and Quality Information Framework (QIF)

Photo credit: Siemens

The Sinamics V20 Smart Access web server module can be mounted directly onto the drive and transform a mobile device or laptop into a virtual operator panel for drive control. By providing a Wi-Fi hot spot, the module’s wireless connection facilitates setup, programming, commissioning, production monitoring, and maintenance on machines and production equipment.

Sinamics V20 can be accessed 100m away even when the drive is difficult to access. The module offers flexibility with iOS and Android operating systems and web browsers Chrome, Safari, and Internet Explorer. A built-in, multi-color LED provides quick communication status readout.

Smart Access monitors speed, current, voltage, temperature, power, and drive servicing, with an overview of alarms, faults, and individual values. Fault codes are transferred via email to a local service provider, while the status of all digital and analog inputs and outputs can be checked immediately. Parameter adjustment, motor test functions, full data back-up, storage, and sharing with fast firmware downloads can all be accomplished via the web server.

Siemens