Metrology's significance in the manufacturing process cannot be overstated. It revolves around the meticulous measurement and analysis of various production components, ensuring stringent quality, pinpoint accuracy, and alignment with precise design specifications. However, as technology evolves, how has metrology adapted to modern manufacturing practices?
In today's manufacturing landscape, millions of components roll off the production line every week, primarily orchestrated by automated processes with minimal human intervention. Each specialised machine in these production lines rigorously adheres to specific product specifications and predefined error margins. Nevertheless, even the most sophisticated and costly machinery, known for their precision, may undergo gradual shifts or alignment variations over time. While these shifts may seem minuscule, they can carry significant ramifications, particularly when these machines are entrusted with crafting critical components for industries such as aerospace and automotive. Enter metrology, a critical player in this scenario.
Traditionally, quality control in manufacturing often involved inspecting finished products once they emerged from the production line. While this approach did identify defects or issues, it was essentially a reactive measure, occurring after the production process. It offered limited opportunities for immediate corrections and usually resulted in a slow feedback loop for process improvement.
In today's era of technological advancement, a paradigm shift has occurred. Real-time data collection and analysis have been seamlessly integrated throughout the entire production process. This means that as products are being manufactured, data is continuously gathered and compared against predefined standards or models. Any deviations or issues are swiftly identified, enabling immediate adjustments to rectify problems in real time. This transformative approach is known as closed-loop manufacturing. Below we’ve highlighted the typical steps you may find during a Closed-Loop Manufacturing process.
The Closed-Loop Manufacturing Process
1. Production Phase
Closed-loop manufacturing starts with the production phase, where physical components or parts are manufactured using various methods, such as additive manufacturing (3D printing), CNC machining, or traditional manufacturing processes.
2. 3D Scanning
3D scanning is a critical step in the quality control process, often carried out either during the manufacturing process or after the production phase is complete. Laser scanners or structured light scanners can be used to carefully capture the exact shape and details of the parts we make. These scanners create a highly detailed 3D digital representation known as a point cloud. This point cloud contains millions of data points, each representing a specific coordinate in three-dimensional space. This is shown as an accurate digital replica of the physical object, capturing every contour, surface detail, and feature with exceptional precision.
3. Comparison to CAD Models
Once the 3D scanning process is complete and the point cloud data is obtained, the next crucial step involves comparing this scanned data to the original models or engineering drawings that serve as the blueprint for the manufactured components. CAD models are created by engineers to specify precise dimensions, tolerances, and geometric features that the final parts must adhere to. During this step, specialised software such as PolyWorks® is employed to align the scanned data with the CAD models. By superimposing the two sets of data, the software can precisely assess the dimensional accuracy and quality of the manufactured components. Any deviations from the design specifications can be quantified and analysed.
4. Deviation Detection
During the comparison between the 3D scanned data and the CAD models, any variations or discrepancies are identified and meticulously analysed. Such as dimensional inaccuracies, deviations in shape, imperfections on the surface, and other quality related issues. PolyWorks® software can then provide detailed reports highlighting where and to what extent these discrepancies exist.
Fixing these issues quickly ensures that the manufactured components meet the required quality standards, resulting in higher precision and better overall product quality.
5. Real-time Feedback Loop
The core of closed-loop manufacturing revolves around setting up a live feedback loop. If any discrepancies are detected they trigger immediate actions to fix the issues, such as adjustments to the process, tooling, or equipment. This causes ongoing improvement of the whole process and the parts being made.
The Evolution of Metrology
Metrology has evolved significantly in recent years which in turn has evolved most manufacturing processes. Traditional metrology methods were often labour-intensive, time-consuming, and limited in their ability to provide real-time feedback. However, with the advent of 3D scanning technology, metrology has taken a giant leap forward. Metrology has advanced far beyond the simple act of taking measurements. It's no longer about analysing past problems, it's about being foresighted and always striving for improvements.
3D scanning now acts as a vital link between the tangible, real-world manufacturing processes and the digital realm. This technological bridge empowers manufacturers to uphold rigorous quality benchmarks, lower expenses, enhance productivity, and swiftly respond to evolving market demands.