In-line visual inspection systems have been employed by manufacturers for many years to automatically spot defects in parts and assembly operations.  In addition to the high costs associated with traditional visual inspection system design, test and deployment, many systems require a large supporting IT infrastructure and costly modifications to ensure proper integration with enterprise legacy systems. Additionally, frequent “false positive” readings (visual inspection system alerts that incorrectly indicate that an assembly defect exists) continue to be a costly and time-consuming issue that manufacturers struggle to control.

Today’s manufacturers need a visual inspection system that can rapidly detect defects in the manufacturing and assembly operations. It must also be affordable, reliable and scalable to the company’s needs. The visual inspection system should easily adapt and integrate with the company’s existing IT infrastructure using off-the-shelf hardware and software designed that is easily trained to handle new inspection tasks.

Rapid Learning and Adaptability

Working with a US-based appliance manufacturer, software engineers at Fraunhofer USA Center Mid-Atlantic and Clemson University have developed and fielded NEXIS, an advanced automated system to help manufacturers identify and eliminate up to 99% of defects in assembly operations.

Manufacturers and assemblers can benefit from NEXIS when they experience difficulty identifying defects in high volume production environments, excessive production downtime required to correct defects, and excessive employee time devoted to verification and correction for any factors affecting production. Examples of production failures that can be addressed by NEXIS include: Deterministic failures (detecting that a part is not present), stochastic failures, but deterministic correct appearance (e.g., detecting excess lubricant on clean, bare metal), and random damage, such as weak or incorrect welds.

A stand-alone camera and software system that visually inspects parts assembly on a production line is the basis of the NEXIS system.  NEXIS references a library of stored images of correctly installed parts and compares this with live images from the assembly line. If the system detects parts that do not meet the quality threshold, i.e., improperly installed, damaged or missing , the software alerts the system operator in real time that the assembly does not pass inspection and requires immediate attention. The system operator can modify or increase the number of image examples of proper installation to increase defect detection accuracy or rapidly adapt to changes in the production line.  

The ability of NEXIS to adapt quickly to changes in the production line comes from the built-in tool for the system operator to modify and increase the number of image examples of proper installations. The tool allows the operator to request a number of possible new examples of proper installations, and the tool returns the most unique examples that it has recently seen. The operator uses their expertise to select the best examples to add and can immediately test the new set of examples on previous parts recorded by the station.

Accuracy and Speed

In today’s supply chain, suppliers are expected to deliver 100% defect-free products, but random sampling of parts for defect inspection is no longer sufficient. As NEXIS focuses on inspecting the specific locations of each part, the total inspection time can be reduced with results delivered in real-time. NEXIS has an inspection throughput of up to five parts in one assembly per second, allowing for the inspection of the entirety of the manufacturing line’s output.

Ease of Installation and Use

NEXIS is a cost-effective alternative for all types of manufacturing processes. The platform is scalable and can rapidly adapt to changes in the production line. It is easy to set up and requires only a laptop or PC and a webcam or machine vision camera. The software is straightforward to use and requires minimal staff training. A flexible web-based interface allows the operator to adapt it to any operating systems they currently use. Built with scalability in mind, NEXIS allows the operator to monitor multiple assembly stations simultaneously on site as well as from a remote location.   

NEXIS saves time, reduces operational and warranty costs, reduces defects, improves quality, and increases production throughput.  NEXIS can spot true defects that can get past traditional quality control systems while also reducing the number of false positives. With production downtime reduced and staff devoted to more important tasks, this saves time, and thus operations costs can be greatly reduced.

With minimal operator training required, Fraunhofer USA CMA engineers can install NEXIS in many production environments in as little as one day.

For more information about NEXIS, Fraunhofer USA CMA and our capabilities to meet the needs of our customers, please contact Dr. Adam Porter, Executive and Scientific Director at  aporter@fraunhofer.org.

About Fraunhofer USA Center Mid-Atlantic (CMA)

Located in College Park, Maryland, Fraunhofer USA CMA conducts applied research to support the software-enabled innovations created by our customers in industry, academia, and government. With a depth of experience in artificial intelligence/machine learning, 5G and NextG networks, Industry 4.0 technologies, and advanced systems and software engineering, the CMA team develops and applies advanced, effective and scalable approaches to software solutions, delivers powerful testing and verification strategies and tools, and uses state-of-the-art measurement and analysis models to support our customers’ needs.