Kusatsu Factory

Integrating advanced technologies and human on-site capabilities for improving productivity and Dbl.ppb-level board mounting quality

OMRON Kusatsu Factory is the site of ultra-high-mix, low-volume production. It produces 4,800 different types of controller product items, 85% of which have a monthly production volume of 20 units or less. To streamline such extraordinary production, we make effective use of manpower that can be flexibly applied. At the Kusatsu Factory, we strive to improve productivity and innovate quality by continuously accumulating and analyzing production line data and by exploring ways to effectively integrate advanced production technologies with human on-site capabilities.

Semi-automation through IE task analysis more than doubles mixed-flow cell line productivity

The Kusatsu Factory employs mixed-flow cell lines for ultra-high-mix low-volume production. Because simply automating such cell lines in their entirety cannot improve productivity or quality in any cost-effective way, we took a more nuanced approach: we scientifically analyzed and evaluated the operating conditions of each process and how the tasks were being carried out in order to determine which tasks to automate or aggregate. Based on our conclusions, we built semi-automated mixed flow cell lines that enable optimal human-machine collaboration to more than double cell line productivity.

Using big data to visualize the entire production line and identify improvement points in 1/6 the time

Effectively improving efficiency and quality in ultra-high-mix low-volume production requires that production site operations be examined from a bird’s eye view to pinpoint the most problematic processes so that targeted changes can be made. At the Kusatsu Factory, data collected from all machines in the printed circuit board (PCB) mounting line is aggregated to create big data, which is analyzed to visualize operation status. Improvement points were traditionally identified by veteran workers with a deep understanding of the products and the lines for producing them. The new visualization system boosted productivity by 30% with 1/6 the time spent on improvement activities. We are now working to reduce the defect rate down to ppb levels.

Visualizing changes in individual PCBs through IOT-powered mounting process innovation

The Kusatsu Factory’s PCB mounting line employs i-BELT, a service for utilizing production site data. It collects data from the PLC as each PCB is sequentially processed by the solder printer, high-speed mounter, multi-function mounter, and reflow furnace, and demonstrates how it transitions over time using a visualization tool. The data is analyzed to investigate factors that negatively impact line utilization rates and pinpoint how the line can be balanced for effective improvements.

Expanding the application range of automation to further boost ultra-high-mix low-volume productivity

Although mixed flow cell lines for ultra-high-mix low-volume production are generally difficult to automate, we are actively automating those parts for which automation is effective. At the Kusatsu Factory, the following processes, for example, have been automated: LED lighting inspections, rotary switch inspections, pick & place of individual parts, and appearance inspections of assembled items. Intra-facility transport of completed products has also been automated using mobile robots.

Automating sensory inspections traditionally reliant on the sensory acuity of veteran workers

Appearance inspections of products were traditionally conducted visually by veteran workers. Not only were these tests effort-consuming and inefficient; their results could be erratic depending on the skills and conditions of the inspectors. At the Kusatsu Factory, sensory inspections have been automated using a system that quantifies inspection points, inspection items, and defect criteria, and learns them in detail through image processing. The automated inspections are more precise and consistent than those conducted by veteran workers.

Ayabe Factory


2-2-1 Nishi-Kusatsu, Kusatsu City, Shiga 525-0035


15 minutes on foot in southwest direction from Kusatsu Station of JR Tokaido Line