Integrated Metrology: The Next Frontier in Manufacturing
Written by Brian Burton
Imagine a manufacturing cell where robots and machines work in concert, assembling complex products with precision.
Image Courtesy of Hexagon Manufacturing Intelligence
One of the significant challenges in modern manufacturing is validating parts as soon as they are manufactured or assembled and identifying defects before further processing. Manufacturing resources often outnumber inspection resources, and the automation of manufacturing processes has outpaced the automation of inspection processes. This disparity creates both a challenge and an opportunity for the future of the metrology industry.
The current metrology market is populated by numerous OEM hardware and software companies that create products intended for a broad array of inspection applications. This universal approach drives sales and provides a return on investment for product development cycles. However, this model also results in a wide array of metrology tools that are often used manually after parts are manufactured. While developing individual metrology devices and software is necessary, relying on this fragmented approach hinders true innovation and efficiency in manufacturing.
The term Industry 4.0 has risen in popularity and refers to the digitization of the manufacturing sector, which includes the rise of data and connectivity, analytics, human-machine interaction, and improvements in robotics. Industry 4.0 requires a shift towards integrated metrology, incorporating dimensional measurement systems with hardware, software, and processes directly into the manufacturing line to provide real-time feedback and drive business decisions. This holistic approach, akin to assembling a complete puzzle rather than accumulating isolated pieces, can lead to significant improvements in productivity and efficiency beyond the incremental gains seen in traditional product development cycles. Successful implementation of such integrated systems involves leveraging recent technological advancements, metrology integration expertise, and disciplined project management throughout the manufacturing process.
Laser trackers have long dominated the portable metrology market due to their combination of portability, accuracy, and data output speeds. They are particularly effective for machine monitoring and part inspection within a cell, although they are limited by cost and single line-of-sight constraints. Structured light products have gained popularity for insitu part inspection and adding value for machine collision avoidance during path planning. Photogrammetry continues to progress, offering comprehensive coverage of a manufacturing cell, with suppliers balancing speed and accuracy in their camera systems. Each one of these key metrology technologies plays a part in providing real time feedback of robot position, part location and part condition. The integration and combination of these various sensors throughout the manufacturing process amplifies the overarching goal of Industry 4.0.
Metrology, manufacturing, and machine control expertise are essential for successful metrology integration projects. Imagine a manufacturing cell where robots and machines work in concert, assembling complex products with precision. At the core of this operation is a sophisticated metrology system, monitoring every movement, position, and operation in real time. One approach to this solution revolves around the integration of metrology into three components of an automated manufacturing process, referred to as a global metrology platform. The system integrates metrology sensors to monitor the robotic motion and correct the position of the robot in real-time, sensors to provide localization of the part in space for the operation and sensors to provide inspection of the part.
This system uses an array of metrology sensors, from laser trackers and high-speed photogrammetry to precision inertial measurement units, capturing detailed data about the manufacturing process. Advanced algorithms then fuse these observations into a cohesive whole, providing a comprehensive, real-time view of the process.
Correct Robot in Real-Time:
At its core, the global metrology platform is designed to enhance the accuracy of the assembly, manufacturing, and inspection processes. It begins with the initial calibration of the robots and machines within the cell. Using a series of poses, the system calculates parameters for an advanced kinematic model, ensuring that every movement is meticulously aligned with the desired specifications. Once calibrated, the system doesn’t rest. Real-time data is continuously fed into the closed-loop metrology control, allowing for dynamic adjustments to the kinematic model. This means that as the robots move, the system is constantly refining their paths, making real-time corrections to ensure that every operation is performed with optimal precision. The result is a level of dynamic accuracy that was previously unattainable, elevating the entire manufacturing process.
In a manufacturing cell populated by multiple robots, the challenge of synchronization is paramount. Each robot must perform its tasks in harmony with the others, maintaining precise coordination to achieve the desired outcome. The global metrology reference system offers a solution to this challenge, enabling all robots to be calibrated and their paths synchronized with a common reference. This ensures that every movement is perfectly timed, allowing for seamless collaboration and higher precision throughout the working volume.
Part Localization:
A key innovation in the integration of metrology within advanced manufacturing is its capacity to enable real-time adjustments, accommodating not only external forces acting on robotic systems but also the dynamic behavior of the manufactured part itself. By leveraging a sophisticated array of high-frequency sensors, this approach precisely tracks the part’s location, allowing for minute part movement compensations to the robot movements. This ensures a seamless alignment between the robot and the part throughout the manufacturing process. The benefits of this methodology are twofold: first, it effectively minimizes environmental influences on the part during production; second, it guarantees that the final product adheres to the highest quality standards.
Part Inspection:
The integration of metrology into the manufacturing process also brings significant benefits to inspection. Traditional methods often involve separate, offline inspection processes that can be time-consuming and prone to errors. With the defined approach utilizing the global metrology platform, inspection becomes intrinsic to the manufacturing process. Every operation is observed by an industrial-grade metrology system, potentially eliminating the need for downstream or offline inspection. This not only streamlines the production process but also ensures that any issues are identified and addressed in real-time.
The potential applications of integrated metrology are vast and varied. In industries ranging from aerospace and automotive to electronics and medical devices, achieving higher levels of precision and accuracy can lead to significant advancements in product quality and manufacturing efficiency. Consider the example of a leading aerospace manufacturer faced with assembling complex components with extreme accuracy. By implementing a global metrology platform in a key production cell, the company enhanced the assembly process’s accuracy and reduced the time required for calibration and inspection. Real-time adjustments ensured that every component met stringent quality standards, significantly improving overall product quality and reducing costly rework.
In another instance, an automotive manufacturer optimized its robotic welding processes using integrated metrology. By continuously monitoring and adjusting the positions of welding robots, the company achieved a previously unattainable level of accuracy, leading to stronger, more reliable welds and reducing defects. This ultimately enhanced the safety and performance of the vehicles produced.
As we look towards the future, integrated metrology holds the key to unlocking the full potential of Factory 4.0. By seamlessly integrating observation and accuracy into every step of the production process, this technology promises to transform manufacturing, driving improvements in quality, efficiency, and innovation. Manufacturers who embrace this technology will be well-positioned to lead their industries, setting new standards for precision and excellence. A global metrology platform is not just a tool for today—it is a glimpse into the future of manufacturing, where the pursuit of optimized efficiency becomes a reality. By harnessing advanced sensors, real-time machine adjustments and insitu part inspections, integrated metrology is the next frontier in manufacturing.
