A Healthy Product Flow
The Medtronic facility in Brooklyn Park, MN, manufactures the Affinity Fusion Oxygenation System, a critical device used during surgery to oxygenate blood. ISyE seniors Jared Burnett, Allan Kim, Betty Huynh, Samantha Klinke, and Zaid Dameh, under the guidance of sponsor Mitchell Nienaber, focused their senior design project on analyzing and improving the inconsistent handling of work-in-progress (WIP) across three production shifts. The existing processes were experiencing underutilization, overproduction, and elevated scrap and rework rates.
The team used both lean and operations research methodologies to address the problem through two solutions: a visual management system and a simulation model that can assess the impact of potential process changes and demand fluctuations.
The existing WIP visual management system faced several challenges, including spatial constraints and a lack of clear indicators for when each product was originally produced. This was particularly problematic, as the manufacturing process utilizes a bonding agent that requires rework if cured beyond a certain timeframe. To address these issues, the team developed a new visual management system centered around a first-in, first-out (FIFO) approach, ensuring timely processing and minimizing the need for rework. To test the concept, the team piloted the system using two redesigned WIP carts, assessing flow and usability before scaling up to full implementation. The finalized system includes seven carts, enhanced signage, and a standardized staging layout, allowing for better inventory control, efficient shift handoffs, and a streamlined workflow.
Pilot testing of the new visual management system indicated that full implementation would result in reduced WIP variability, improved FIFO compliance, and a decrease in rework. Additionally, the new system improved coordination among workers from different shifts. Along with other solutions, such as implementing redesigned carts to improve ergonomics and staging compliance, and developing visual cues and labeling to improve production flow tracking, the team was able to reduce rework and labor waste, improve operational control, and achieve greater flexibility through scenario-based planning.
The team also developed a discrete-event simulation model to enable Medtronic to test production scenarios, including varying cycle times, staffing levels, and throughput targets. Ultimately, the team found that adding a centrifuge to the production line would have the most positive impact on product flow and WIP. The model was developed as a hybrid solution leveraging both Simio (a simulation software program) and Excel VBA platforms, so that Medtronic can continue to utilize it in future work.
Through their work with Medtronic, the seniors learned the importance of early problem definition, stakeholder engagement, and expectation alignment, as well as testing small, iterative improvements to achieve greater outcomes. The team came away with a better understanding of one of Minnesota’s most well-known companies, as well as an understanding of building buy-in and delivering practical, sustainable solutions.