Technical Papers & Journals

Integration of Laser Tracker System in BIW Measurement: A Case Study in the Automotive Industry

Volume 16, Issue 1

Armağan Altınışık and Emre Bolova, TOFAS

Product and process quality assurance are challenging tasks due to increasingly narrowing product specifications. Coordinate measurement is one of the key technologies used to inspect and improve the accuracy of produced components. Dimensional inspection tasks are often carried out on conventional coordinate measuring machines (CMMs). However, there are strong concerns about CMM usage due to low measurement capacity, a lack of speed and flexibility, and limited accessibility to points underneath and inside the body of parts under test. To overcome these challenges, manufacturers in the automotive sector must adapt laser scanning technologies. However, according to a limited study of the current literature, scanners are less accurate than CMMs fitted with touch probes. In this article, we summarize a project using uncertainty and measurement system analysis (MSA) to assess body geometry measurement capability with an off-line laser scanning system compared to a touch-probe CMM. The obtained results demonstrated that the uncertainty and gauge repeatability and reproducibility (GRR) values of laser scanning technology are very satisfactory for body geometry measurements. In addition, scanners offer improved measurement capacity due to increased speed and better accessibility to the part vs. CMMs.

Investigations of a Hand-Held Laser Scanner to Estimate Fracture Apertures and Roughness of Natural Rock Formations

Volume 16, Issue 1

Christoph Naab and Sina Hale, Karlsruhe Institute of Technology (KIT)

Demanding requirements, like high resolution and a low uncertainty in the range of micrometer, are essential in applications concerning natural rock formations. In the field of applied geoscience, these requirements are needed, for instance, to estimate the necessary parameters in the modeling of geological processes with sufficient quality. Investigations have been carried out with a hand-held laser scanner in combination with an articulated measuring arm to evaluate if these requirements could be achieved. The laser scanner utilizes triangulation and uses enhanced techniques to obtain higher frequency scan rates as well as optimized sensor performance for measuring non-homogeneous surfaces. These studies have estimated the minimum fracture apertures with a focus on the complete process of measurement, data analysis, and traceability to get a reliable result for the estimation and the uncertainty. Furthermore, investigations have been undertaken concerning the determination of roughness of a bedding joint where results have been compared to an established and independent method.

Case Study of a Fuselage Join Automation

Volume 16, Issue 1

Rob Flynn, Nathan McRae, and Spencer Thompson, Electroimpact

A large jet fuselage consists of forward, center, and aft sections which must be joined together. The join process calls for a rough move to a “stage” position, automated measurements, and calculation of a transformation matrix to yield a move to an accurate “pre-join” position from which the manual join process is started. After the manual join is complete the fuselage sections are measured again, and the final locations recorded. Because the process of measurement, transformation calculation, and data transfer to the programmable logic computer (PLC) is an involved series of events, the customer chose to automate it and thereby ensure a repeatable and reliable result. In this article we examine the solution, look at some of the challenges faced, review the results, and consider some lessons learned.

Simple Methods for Dynamically Testing Laser Trackers in the Field

David H. Parker

Laser trackers are typically evaluated under the ASME B89.4.19 standard using artifact standards under static conditions. Due to the requirements of the artifact standards, evaluations are typically beyond the capabilities of most laser tracker owners and...

2020 CMSC PRESENTATION: CMM Verification of Low Pressure Turbine Blisk under Spin Testing of a Small Turbofan Engine

Suneel Kumar, Marakandeya V, MuralidharanV, Sreelal Sreedhar

Spin testing testing of the integrated bladed rotors or blisks is being increasingly used for the better understanding and validation of life and integrity. The test is carried out in various steps and goes thorough rigorous monitoring and inspection...

2020 CMSC PRESENTATION: Case Study of a Fuselage Join Automation

Rob Flynn, Nathan McRae, and Spencer Thompson

A large jet fuselage consists of forward, center and aft sections which must be joined together.  The join process calls for a rough move to a “stage” position, automated measurements, and calculation of a transformation matrix to yield a move to...

Beyond Best-Fit, Spatial Compensation of Metrology Data

Edward West, Christopher Jamieson, Garrett Kelley

Current digital compensation techniques for uncontrolled boundary conditions such as profile at station lines and profile-per-unit-length (PPUL) fall short of accurately characterizing deformed flexible structures. Janicki Industries has developed Spatial...

2020 CMSC PRESENTATION: Magnet Fiducialization for the Advanced Photon Source Upgrade Project

W. Jansma, C. Doose, S. Izzo, A. Jain

2020 CMSC PRESENTATION: From High-resolution Imaging to High-precision Metrology with 3D X-ray Microscopes

Naomi Kotwal, Herminso V. Gómez, et al.

2020 CMSC PRESENTATION: Beyond Best-Fit Spatial Compensation of Metrology Data

Edward West, Chris Jamieson, Garrett Kelley

Technological progress over the last decade has allowed metrology professionals to efficiently collect accurate and comprehensive datasets on large complex structures. With contemporary software, analysts distill meaningful results with unprecedented...