Has the Use of Robotics Improved Medical Device Manufacturing?
Today, robotic automation is integrated into nearly every facet of medical device processing and production. MICRO’s Steven Jacobsen, manager of process development engineering, answers a few questions on how robotics is maximizing throughput, speed, and efficiency in medical device manufacturing. MICRO is a full-service contract manufacturer of precision medical devices, injection and insert molding, metal injection molding, fabricated tube assemblies, sub-assemblies, and complete devices.
Has the COVID-19 pandemic brought a new urgency to automating medical device manufacturing?
Jacobsen: Consistency, cleanliness, and reduced touch points have always been important drivers in automating medical device manufacturing processes. In today’s world of coronavirus (COVID-19), however, there is an even greater need to reduce human, machine, and product interaction. Manually progressed components in this environment carry risks that have not been seen before. Previously it was very common to utilize a serial approach to work cells where operators would perform tasks on a component or assembly and pass these components to the next operator in close proximity.
Today’s social distancing and plexiglass dividers used to prevent contamination have made these operations even less efficient while further increasing operating costs. Surface contamination on an in-process medical device assembly or component may pose a low risk to technicians when precautions are taken; nonetheless, if it can be avoided, it should. This unfortunate situation has only highlighted the benefits of true start-to-finish automated processes. Automation has also decreased the temporary impact of losing staff members to COVID-19-related family leave.
Overall, MICRO and the industry as a whole would have been significantly more impacted had we not made such a strong investment into these critical systems. Even without these factors, robotic systems in medical device manufacturing still offer significant benefits. The ability to move with the dexterity of a human hand yet with greater speed, consistency, and tighter tolerances remains a great financial incentive. Our stainless-steel tube processing area, for example, today looks completely different than it did a decade ago. Ten years ago, you would have seen a room filled with people in close proximity, performing different tasks, such as running machines and inspecting components. Today, that same room is filled with networked automated cells and one individual to oversee their operation.
What factors have enabled manufacturers to fully integrate robotics into production workflows?
Jacobsen: The advent of the Industry 4.0 revolution, or the fourth industrial revolution, through the use of modern technology has opened up many doors for systems integration. This has increased the speed at which these tools can been integrated into production workflows. The advancement of machine communication protocols such as Ethernet IP and continued adoption of OPC-based data flows has greatly reduced the complexity of integrating robotic automation into existing workcells. These features have now become a standard for us and have allowed us to see into these state-of-the-art systems through various analytic tools. This has increased both shop floor visibility and overall uptime with the associated benefits of predictive maintenance that this data provides. These technologies have even allowed our technical team to more efficiently troubleshoot a wide variety of issues with both robotic cells and other networked machines. The advantages of this have never been more apparent since, in many cases, this troubleshooting has occurred remotely while the engineer was working from home. The “New Normal” would not have been possible for our manufacturing engineers without this approach.
What production processes are especially well suited to robotics?
Jacobsen: In some cases, automating a process to protect the operator is just as much an incentive as the other financial benefits. The COVID-19 pandemic has brought to light the potential risks of infectious disease transmission through blood-borne pathogens, airborne atomized droplets, and surface contact transmission. A risk assessment will clearly show that areas where sharps are being fabricated will be one of the higher-risk operations that is therefore ideally suited to robotic automation. For MICRO, this was the grinding and processing of medical sharps, where components are extremely delicate and need to be produced in high volumes. Robotics can help protect operators from accidental sticks and protect the sharps from damage, both of which are common challenges in medal sharps production.
In addition, another factor that has driven the use of automation is the throughput requirements and strict quality and cleanliness standards in medical device manufacturing. We have successfully integrated six-axis robotics into several of our grinding cells, allowing us to load strips of sharps into various fixtures for sharpening and deburring. A human operation would simply not be able to replicate the accuracy required to place these components and the tight tolerances associated with this type of operation.
What other manufacturing challenges can robotics help address?
Jacobsen: Some new areas of focus for robotics include cleaning and deburring of in-process components. Collaborative robotics working alongside semi-automated workcells are now being utilized more and more to complete these types of tasks previously thought to be too delicate or requiring too much feedback for automated systems. At MICRO, we are exploring the use of these flexible systems to replace some of the hand deburring operations that became an unexpected part of our process. Again, these are not the typical applications you would think of when envisioning integrated robotics. Traditional applications have been focused on machine tending but there are many instances where a machine such as a Swiss screw machine or five-axis mill with a tube feeder can operate unattended for long periods of time without intervention. The post-processing required, however, can now be handled at the point of creation without impacting cycle times. This can eliminate the need for some manual deburring or mass finishing operations.
Force feedback sensors integrated into the robotic end-of-arm tools in combination with rapidly advancing and customizable vision algorithms are now more integrated than ever. This has allowed us to explore automating these types of operations that require dynamic changes to be made based on burr conditions in steel from tool wear, flash from a molded component, or even visual feedback such as excessive oxidation due to heat. Deburring against an abrasive wheel with robotics requires various amounts of pressure from different angles of attack, and the amount of pressure is dynamic based on the input variable and abrasive conditions. All of this can now be factored in with the use of these advanced tools to output a uniform and consistent product that was not previously achievable.
What are some other applications for robotics that you are currently utilizing?
Jacobsen: Visual inspection and packaging of sharps is another area where leveraging robotics can be quite useful. We have had great success adding compact, higher-speed robot arms to needle packaging, inspection, and singulation machines, as their size and acceleration rates are well suited for these operations. Concurrent tasks can be performed in different work cell areas, which has been particularly useful in packaging applications and in handling needles and sharps. Automated processes leveraging this type of robot arm allow for packaging components of various sizes and shapes with high speed and precision and yield efficient, consistent packaging, which is critical for downstream partners.
Tubing production is well suited to robotics automation. In collaboration with one of our partners, we recently designed a flexible four-axis laser cutter capable of handling various input lengths, diameters, and thickness tubes as an automated solution to achieve high component volumes. This application is particularly useful for producing stainless-steel support tubes for new medical devices with complex design features. The system uses a series of vision cameras to orient the tube based on a preformed shape as well as to locate the start of the CNC laser-cutting program with each component.
In addition, we were able to dedicate one robotic system to serve two machines but using a six-axis robot to replicate the exact movements of an operator’s hand to remove the finished part, and in the same motion insert the blank tube through the machine’s rotary actuator. The integration of these two cells resulted in each machine being able to run unattended for four consecutive hours, which increased production efficiency and reduced cosmetic defects as well as the need for frequent in-process inspections.
Based on the success of this project, we integrated an additional machine with an even more dynamic approach for component flexibility. This cell was designed to produce different families of components and different combinations of diameters and lengths. To verify that the components that were loaded manually to rack matched the cutting program as intended, we leveraged the flexibility of the robot and integrated simple vision sensors outside the cutting area to simulate a visual check. In addition, sensors were integrated to the gripper that could verify the diameter and confirm it had the correct tube based on how far its fingers closed. The inputs allowed us to utilize an automated solution in a high product mix environment.
We also use robotics to handle a variety of operations in one integrated cell during the pad-printing process. Robotic automation is useful for tubing components with extremely delicate components that are subject to scratching, along with a high throughput required for the product line. We created a cell that uses a six-axis robot in combination with a series of actuators to pick from rack. We incorporated a sophisticated vision system into the work cell system, with cameras at several locations in the pad-printing process for in-process inspection and final inspection. Machine operators can manage multiple machines on the shop floor while the robot does the rest.
The vision system can verify orientation and load the component into the printer. In addition, it can calculate the radial orientation from randomly loaded components in milliseconds and translate that to dynamic code that provides the exact coordinate to load a tube on an alignment pin with 0.002 in. of clearance every time, optimizing cycle time and accuracy. Scratching of the tube surface is eliminated, and no ink from an operator’s hands is accidentally deposited on the OD. Tubes can be unloaded, inspected with additional vision sensors utilizing OCR technology (optical character recognition) to verify the readability of text, and scored to determine acceptance.
Overall, today’s automated work cells are already an integral facet of medical device manufacturing. The pandemic of 2020 has only reinforced the necessity to progress further toward automated cells for both the health and safety of our workforce as well as the continuity of the supply chain. Like most medical device manufacturers, our company was considered an essential business from the start of the pandemic. Ensuring supply continuity of these lifesaving devices and tools that we offer is no easy task in these conditions. While the industry has continued to trend in the direction of increased automation for years, sometimes it takes an even more extreme catalyst to make real sustained change. Innovative solutions with robotics, data analytics, shop floor visibility, and remote support are some of the many tools that have allowed us to achieve our goal of delivering product on time and without compromise to the safety of our workforce.
Article source:MDDI Online