Mark Crawford, Contributing Writer 05.06.16
Medical devices continue to become smaller and more complex. End users—both medical professionals and patients—expect medical products to reflect the same quality and technology in the other products they use. This means well-thought-out user interface designs, top materials and finishes, and positive experiences using the product. To stay competitive and meet these customer demands, medical device manufacturers (MDMs) are designing products that expand functionality and use more efficient platforms, including modifications to legacy products that improve market penetration and keep R&D costs down.
“Device OEMs continue to push design platforms to include increased functionality, so that their products can support wider clinical capabilities,” said Patrick Meheran, director of silicone operations for Polymer Conversions Inc., an Orchard Park, N.Y.-based medical contract manufacturer. “This continually pushes contract manufacturers to meet those increased capabilities.”
Not only do MDMs value innovation and creative design, they also crave shorter lead times and lower costs. Speed to market is paramount these days as OEMs scramble to get their products to market before their competitors. As such, they are doing whatever they can to increase efficiency and save time. This includes reducing complexity whenever possible, using proven materials, and doing more testing and analysis up front—for example, finite element analysis (FEA)—even before prototypes are built, to knock out as many potential design problems as possible.
“There is definitely a greater emphasis on including risk analysis during the device design,” Meheran added. “These decisions early on help streamline quality and manufacturing planning processes.”
As timelines get squeezed, more MDMs turn to rapid design and prototyping to shorten design cycles. Technologies that can make this happen quickly, such as additive manufacturing (AM) and 3D printing, continue to advance rapidly. Yet equally important for saving time is something as simple as being able to communicate clear design criteria. If product requirements are clearly defined in advance (for example, size envelope, weight limits, materials used, intended function, etc.), the design process is more efficient and “scope creep” can be avoided.
“For example, in the sterilization case and tray market, the compressed cycle is very evident,” said Ron Estes, vice president of operations for Estes Design and Manufacturing Inc., an Indianapolis, Ind.-based sheet metal fabricator that has served the medical industry for over 30 years. “Orthopedic OEMs will design a new system with its corresponding instrumentation. Once the instrument designs are settled, attention is turned to the tray that holds them. The challenge then becomes completing the design, prototyping, and production ramp-up of the case and tray system within the remaining time window, prior to product launch.”
Device Connectivity
MDMs are being greatly influenced by the “Internet of Things”—the interconnectivity among devices that enables real-time transmission of data. In healthcare, this includes wearable electronics that record and transmit health data, either to physicians or patients. The field of mobile or digital health is growing rapidly, using advanced sensor technologies and wireless components. More devices are integrated with sensing- and/or software-combined products to engage users and produce data that can be analyzed for predictive diagnostics and to improve patient compliance with drug and therapeutic regimes.
“Interest in electromechanical design has risen significantly, due in part to home use of devices, wearables, and remote monitoring,” said Holly Smith, business development manager for EG-GILERO, a Durham, N.C.-based drug delivery and medical device design, development, and manufacturing company. “Users and healthcare providers are viewing devices as an extension of their minds and bodies. These devices must be smarter, faster, and effortless.”
This is especially true in key growth areas such as point-of-care (POC) diagnostics and patient-delivered injection therapy—for example, diabetes management. “In the area of POC diagnostics, there is considerable effort to improve the patient experience in daily glucose testing,” said Mark McElfresh, vice president of operations and supply chain at The Tech Group, a Tempe, Ariz.-based contract manufacturer of pharmaceutical, diagnostic, and medical devices. “Continuous glucose meters are expanding as a market, enabling patients to reduce the number of times they have to pierce their skin to test their blood glucose levels.”
Perhaps the biggest challenge for POC is ease of use. More products are being designed for patients to use at home—to capture medical data without going to a lab. It is essential for this process to be easy to follow and understand—something that does not necessarily come easily to engineers. Human factors engineering is being used more often to optimize end-user interaction with the device and maximize compliance with the recommended treatment plan.
“Increasingly, patients are collecting their own samples and sending them to processing facilities for analysis,” said Curt Anderson, founder of Compass Product Design Inc., a Pleasanton, Calif.-based product design and engineering consulting firm and a subsidiary of Molded Devices Inc. “For these types of products, it is essential to focus on a device design that makes the entire experience of using the device simple, intuitive, and foolproof for the target population.”
More devices have electrical and software elements that “talk” to mobile products or send data to the cloud. Being able to seamlessly collaborate with other disciplines—for example, electronics—is a more holistic approach that is crucial for designing medical devices in today’s market. Cloud computing also could have a big impact on computer-aided design (CAD). For example, more programs like OnShape bring Google Docs-type collaboration to the CAD world.
“OnShape is a full-cloud, 3D CAD system and runs on mobile and desktop browsers,” said Fan Zhang, senior mechanical engineer for Stratos Product Development, a Seattle, Wash.-based product development firm serving the medical device and consumer electronics industries. “Multiple designers can work on the same CAD assembly thousands of miles apart. Although there are still a few issues with this software, I think some bigger companies, such as Creo or Solidworks, will eventually go this route.”
Trusted Design Partners
As medical device designs become smaller and more complex, OEMs increasingly rely on contract manufacturers and technology consultants to enhance their designs, sometimes even taking nonviable designs and turning them into successful products. Outsourcing to third-party design firms is a standard practice for larger medical device and pharmaceutical companies. This approach brings more knowledge to the table and ensures OEMs are getting the latest technologies designed into their products. For some companies, outsourcing is also a cost-control measure in response to the 2.3 percent tax that had been levied on medical device sales for several years until the two-year suspension that passed in late 2015.
“Increasingly, the capabilities required to develop high-value health ecosystems are embedded in only a few OEMs, meaning most of them must utilize collaborative teams and partnerships,” said Aidan Petrie, chief innovation officer and co-founder of Ximedica, a Minneapolis, Minn.-based developer of medical technologies.
OEMs design two types of products: 1) brand-new devices that often depend on the latest technologies, materials, and methods; and 2) redesigns of legacy products, which already have a track record of market success, regulatory approval, and brand recognition. They also tend to be less costly, and easier and faster to get into the marketplace.
“In general, it seems that funding for new technologies is down,” said Anderson. “Investors are more focused on a clear road to profitability over revenue growth, which can be difficult for some emerging medical device technologies.”
OEMs are intent on getting new products and technologies into the marketplace quickly and reducing the time to product launch. This typically requires maintaining a product development pipeline or identifying novel solutions/variations that will yield high-value intellectual property. “For legacy products, medical device manufacturers are looking for design improvements that allow existing technologies to be used in a wider variety of environments, such as outsource clinics, the home, and other emerging markets, as well as by broader user groups,” said Petrie.
Improvements to legacy products are highly dependent on cost sensitivity and preservation of regulatory approvals. “This is a balancing act of spending the least amount of money to retain the market position, while also identifying opportunities to improve margins through sourcing, slight cosmetic design changes, or material selection, all while ensuring previous regulatory approvals remain intact,” said Smith.
Regardless of whether the design is for a new or legacy product, the top priority should always be design for manufacturability (DFM). OEMs want a design partner that will work with them throughout the value chain. DFM is critical for identifying and resolving potential limitations in early designs and developing the best possible production process. “As designs get more complex, it becomes more critical to do DFM up front—sometimes before any quoting takes place,” said John Budreau, director of new business development for PTI Engineered Plastics Inc., a Macomb, Mich.-based provider of custom plastic injection molding.
“Using a risk-based approach to eliminate potential failure modes and reduce complexity of the manufacturing process is absolutely necessary,” agreed McElfresh. “Driving out complexity while building in reliability is the best way to improve the overall patient experience. DFM also allows for better management of the product lifecycle and creates a well-planned path to focused process and product improvement.”
Technology Advances
DFM takes into account the latest materials and technologies—the right combination depends on a multitude of factors, including performance specifications, end-use environment, budget constraints, and volume of production. For example, is the product required to be bacteria resistant? With the ever-increasing focus on reducing hospital-acquired infections, one DFM consideration would be selecting laser welding of light-gauge stainless steel for medical and pharmaceutical products. More MDMs are selecting laser welding because traditional welding methods are subject to cracks, crevices, and inclusions where bacteria or fungi could grow, creating potential health risks in hospital settings.
“Laser welding eliminates those dangers,” said Estes. “Precise control of the laser output and precise positioning of the laser beam combine to create a surgically precise, fusion weld. The speed of the laser welding process limits the heat-affected zone, which improves quality. The assist gases are key to supporting the molten metal joint and keeping it free of impurities, such that when it cools and solidifies there is a smooth finish. The precision in the laser welding process requires precision in component manufacturing, as the tolerances for welded corners are as tight as 0.005 inches.”
Additive manufacturing and 3D printing are evolving at a rapid pace, continuously improving in capacity, part size, speed, and materials, including printable polyether ether ketone (PEEK). 3D printing can be used to make complex parts and products that can be manufactured in no other way, especially customized, patient-specific products. Engineers utilizing AM or 3D printing have more design options. Because 3D printing is such a disruptive industry and expected to bring so many improvements to manufacturing in the coming years, some companies in other manufacturing industries are training their engineers to “design to the process”—coming up with innovative new products designed specifically for 3D printing. This puts them at the top of the learning curve, and ready to capture new market opportunities quickly.
As impressive as 3D printing is for making complex parts, perhaps its greatest use so far in the medical device industry is more practical—improving operational efficiency by printing prototypes. This allows the product development team to get their hands on a prototype in a matter of hours rather than days, allowing them to evaluate and validate product designs very quickly, without the expense of putting a part into metal. 3D printing can also be used to make replica instruments or provisionals that are helpful in designing cases for the real instruments.
“Fit and function are key factors of case design, so being able to trial-fit instruments into a case is essential,” said Estes. “Unfortunately, instrument sets from an OEM are hard to come by, so we print our own. Obviously, the mass of a real instrument cannot be replicated, but our plastic versions allow us to evaluate fit in the tray, as well as ease of placement and ease of removal.”
3D printing and other forms of rapid tooling have continued to push the molding envelope. Opportunities to help reduce mold cycle time through conformal cooling have come to the forefront in the last couple of years with the continuing development of metal additive manufacturing machines. “Despite the fact the inserts coming out of these machines still need some post-processing to be ready for molding, they can reduce the total mold build time,” said Scott Kraemer, directing manager of new technology for PTI. “However these machines can easily run around two to five times the cost of a standard computerized numerical control (CNC) machine, so not every shop can afford to add this to their tool box.”
Less material waste (and cost) is an advantage of additive manufacturing over subtractive methods. Rather than cutting the excess away in chip form and recycling the scrap, operators build up only what is needed for each insert. “In some instances, you can grow the inside of the insert with a less dense melt, providing an additional savings of material,” said Kraemer. “Therefore you only pay for what you use, instead of buying a large block and throwing away about a third of it.” However, he noted, not every insert is a good fit for the additive process—some of the more basic, simple parts can still be done faster with subtractive manufacturing.
Growing the inserts with the additive process also makes it easier to accommodate the precise placement of thermocouples (or other inserted objects) with slight-to-moderate contours to get around ejection or other intrusive part areas, which is harder to do with conventional drilling methods. This provides a more robust and consistent processing window.
“Although 3D printing is very useful as a rapid prototyping method for early feedback on designs, we still have a ways to go before 3D printing of plastics replaces traditional manufacturing approaches such as injection molding, when considering part cost at higher volumes,” said Zhang. “A molded part can still be several orders of magnitude less costly than a 3D-printed part at high volumes.”
A tremendous amount of research is being conducted on advanced materials for additive manufacturing, 3D printing, and injection molding. High-tech plastics are engineered to have enough strength and thermal and chemical resistance to replace traditional metal parts (stainless steel and titanium, for example). Medical device manufacturers are utilizing high-temperature materials such as PEEK and polyphenylene sulfide that require mold temperatures up to 400 degrees F and processing temperatures between 600 and 700 degrees F.
“Many of these applications or devices are used in environments or procedures that require the plastics to withstand higher operating temperatures, or replace metal-machined components,” said Budreau. “PTI has a dedicated, high-temperature molding cell with equipment and tooling designed specifically for processing high-temperature resins.”
In another PEEK example, Molded Devices is developing a compounded PEEK containing carbon nanotubes and barium sulfate that will be used for injection-molded spinal screws. “The compound is treated to allow better bone cell adhesion, as well as addressing the patient population that rejects titanium implants,” said Anderson. “There is also a significant cost [reduction] when used as an alternative to the current titanium screws.”
Moving Forward
Many new medical device design and development opportunities are being driven by regulatory interests in human factor considerations (intuitiveness of devices), readmission reduction, never event lists (healthcare delivery quality reporting initiative), and reprocessing of reusable equipment. “Over the past several years, testing and documentation of the user interface and the usability of the product, have become a bigger part of the development process and timeline,” said Anderson.
For well-established or large OEMs, the goal is speeding up navigation within the regulatory process—having the knowledge of current regulatory changes and delivering optimal recommendations based on specific device class and requirements.
“In contrast, small and medium-size clients gain the most by finding ways to optimize their approach to working with FDA,” said Smith. “This often comes down to their predicate device selection. This is critical for design—recognizing the key device characteristics and finding the best fit predicate device or lack thereof will dictate the time and effort required for filing.”
Challenging design-related requests for contract manufacturers include tight timelines, special circumstances tied to clinical builds, unique design characteristics, U.S. Food and Drug Administration snags, and short development cycles for market-ready prototypes. CMs use a variety of materials, techniques, equipment, methods, and know-how to make it happen—including combining solutions in creative ways.
“Many OEMs miss opportunities to improve designs for high-speed manufacturing by not fully understanding the possibilities of hybrid manufacturing,” said McElfresh. “Hybrid manufacturing techniques such as multi-component molding, insert molding, and sintered metal integration can reduce the number of components. Hybrid manufacturing can also eliminate complicated assembly steps such as heat-staking, gluing, bonding, or welding. Often, OEMs fall into the trap of looking at the initial capital investment only and forget to consider the overall reliability, cost savings, and patient risk reduction of hybrid manufacturing approaches.”
With the intense focus on connectivity, the area that may expand the most rapidly will be computing/memory infrastructure for devices, which is also becoming more accessible and simpler to use than ever before. This makes it easier for designers to tap into that infrastructure and create new applications and intelligence for their products. “They no longer need to create the core infrastructure—it’s already there for them to use,” said Anderson.
Key drivers of complexity in medical devices—improved functionality, advanced materials, and miniaturization—continue to create cost pressures on contract manufacturers. Expectations of patients and doctors have never been higher. Medical reimbursements are increasingly tied to the quality of patient outcomes. How quickly can a new product be developed? How valuable is it to shorten the timeline? Human factors are influencing design more than ever before—having a clear picture of user needs, at design inception, will drive down development costs and speed up development time. Technologies now available for rapid prototyping allow designers to iterate faster and at lower cost, yielding design solutions that are more effective from the onset.
“Accelerating development timelines can be one of the greatest challenges for MDMs, and also the biggest competitive advantage,” said Smith. “Relying on trusted partners that can bring your new technology to life quickly will make or break you. It’s really about staking claim early to novel design concepts that ease the delivery model in the form of relaxed cost pressure or increased patient satisfaction.”
Mark Crawford is a full-time freelance business and marketing/communications writer based in Madison, Wis. His clients range from startups to global manufacturing leaders. He also writes a variety of feature articles for regional and national publications and is the author of five books. Contact him at mark.crawford@charter.net.
“Device OEMs continue to push design platforms to include increased functionality, so that their products can support wider clinical capabilities,” said Patrick Meheran, director of silicone operations for Polymer Conversions Inc., an Orchard Park, N.Y.-based medical contract manufacturer. “This continually pushes contract manufacturers to meet those increased capabilities.”
Not only do MDMs value innovation and creative design, they also crave shorter lead times and lower costs. Speed to market is paramount these days as OEMs scramble to get their products to market before their competitors. As such, they are doing whatever they can to increase efficiency and save time. This includes reducing complexity whenever possible, using proven materials, and doing more testing and analysis up front—for example, finite element analysis (FEA)—even before prototypes are built, to knock out as many potential design problems as possible.
“There is definitely a greater emphasis on including risk analysis during the device design,” Meheran added. “These decisions early on help streamline quality and manufacturing planning processes.”
As timelines get squeezed, more MDMs turn to rapid design and prototyping to shorten design cycles. Technologies that can make this happen quickly, such as additive manufacturing (AM) and 3D printing, continue to advance rapidly. Yet equally important for saving time is something as simple as being able to communicate clear design criteria. If product requirements are clearly defined in advance (for example, size envelope, weight limits, materials used, intended function, etc.), the design process is more efficient and “scope creep” can be avoided.
“For example, in the sterilization case and tray market, the compressed cycle is very evident,” said Ron Estes, vice president of operations for Estes Design and Manufacturing Inc., an Indianapolis, Ind.-based sheet metal fabricator that has served the medical industry for over 30 years. “Orthopedic OEMs will design a new system with its corresponding instrumentation. Once the instrument designs are settled, attention is turned to the tray that holds them. The challenge then becomes completing the design, prototyping, and production ramp-up of the case and tray system within the remaining time window, prior to product launch.”
Device Connectivity
MDMs are being greatly influenced by the “Internet of Things”—the interconnectivity among devices that enables real-time transmission of data. In healthcare, this includes wearable electronics that record and transmit health data, either to physicians or patients. The field of mobile or digital health is growing rapidly, using advanced sensor technologies and wireless components. More devices are integrated with sensing- and/or software-combined products to engage users and produce data that can be analyzed for predictive diagnostics and to improve patient compliance with drug and therapeutic regimes.
“Interest in electromechanical design has risen significantly, due in part to home use of devices, wearables, and remote monitoring,” said Holly Smith, business development manager for EG-GILERO, a Durham, N.C.-based drug delivery and medical device design, development, and manufacturing company. “Users and healthcare providers are viewing devices as an extension of their minds and bodies. These devices must be smarter, faster, and effortless.”
This is especially true in key growth areas such as point-of-care (POC) diagnostics and patient-delivered injection therapy—for example, diabetes management. “In the area of POC diagnostics, there is considerable effort to improve the patient experience in daily glucose testing,” said Mark McElfresh, vice president of operations and supply chain at The Tech Group, a Tempe, Ariz.-based contract manufacturer of pharmaceutical, diagnostic, and medical devices. “Continuous glucose meters are expanding as a market, enabling patients to reduce the number of times they have to pierce their skin to test their blood glucose levels.”
Perhaps the biggest challenge for POC is ease of use. More products are being designed for patients to use at home—to capture medical data without going to a lab. It is essential for this process to be easy to follow and understand—something that does not necessarily come easily to engineers. Human factors engineering is being used more often to optimize end-user interaction with the device and maximize compliance with the recommended treatment plan.
“Increasingly, patients are collecting their own samples and sending them to processing facilities for analysis,” said Curt Anderson, founder of Compass Product Design Inc., a Pleasanton, Calif.-based product design and engineering consulting firm and a subsidiary of Molded Devices Inc. “For these types of products, it is essential to focus on a device design that makes the entire experience of using the device simple, intuitive, and foolproof for the target population.”
More devices have electrical and software elements that “talk” to mobile products or send data to the cloud. Being able to seamlessly collaborate with other disciplines—for example, electronics—is a more holistic approach that is crucial for designing medical devices in today’s market. Cloud computing also could have a big impact on computer-aided design (CAD). For example, more programs like OnShape bring Google Docs-type collaboration to the CAD world.
“OnShape is a full-cloud, 3D CAD system and runs on mobile and desktop browsers,” said Fan Zhang, senior mechanical engineer for Stratos Product Development, a Seattle, Wash.-based product development firm serving the medical device and consumer electronics industries. “Multiple designers can work on the same CAD assembly thousands of miles apart. Although there are still a few issues with this software, I think some bigger companies, such as Creo or Solidworks, will eventually go this route.”
Trusted Design Partners
As medical device designs become smaller and more complex, OEMs increasingly rely on contract manufacturers and technology consultants to enhance their designs, sometimes even taking nonviable designs and turning them into successful products. Outsourcing to third-party design firms is a standard practice for larger medical device and pharmaceutical companies. This approach brings more knowledge to the table and ensures OEMs are getting the latest technologies designed into their products. For some companies, outsourcing is also a cost-control measure in response to the 2.3 percent tax that had been levied on medical device sales for several years until the two-year suspension that passed in late 2015.
“Increasingly, the capabilities required to develop high-value health ecosystems are embedded in only a few OEMs, meaning most of them must utilize collaborative teams and partnerships,” said Aidan Petrie, chief innovation officer and co-founder of Ximedica, a Minneapolis, Minn.-based developer of medical technologies.
OEMs design two types of products: 1) brand-new devices that often depend on the latest technologies, materials, and methods; and 2) redesigns of legacy products, which already have a track record of market success, regulatory approval, and brand recognition. They also tend to be less costly, and easier and faster to get into the marketplace.
“In general, it seems that funding for new technologies is down,” said Anderson. “Investors are more focused on a clear road to profitability over revenue growth, which can be difficult for some emerging medical device technologies.”
OEMs are intent on getting new products and technologies into the marketplace quickly and reducing the time to product launch. This typically requires maintaining a product development pipeline or identifying novel solutions/variations that will yield high-value intellectual property. “For legacy products, medical device manufacturers are looking for design improvements that allow existing technologies to be used in a wider variety of environments, such as outsource clinics, the home, and other emerging markets, as well as by broader user groups,” said Petrie.
Improvements to legacy products are highly dependent on cost sensitivity and preservation of regulatory approvals. “This is a balancing act of spending the least amount of money to retain the market position, while also identifying opportunities to improve margins through sourcing, slight cosmetic design changes, or material selection, all while ensuring previous regulatory approvals remain intact,” said Smith.
Regardless of whether the design is for a new or legacy product, the top priority should always be design for manufacturability (DFM). OEMs want a design partner that will work with them throughout the value chain. DFM is critical for identifying and resolving potential limitations in early designs and developing the best possible production process. “As designs get more complex, it becomes more critical to do DFM up front—sometimes before any quoting takes place,” said John Budreau, director of new business development for PTI Engineered Plastics Inc., a Macomb, Mich.-based provider of custom plastic injection molding.
“Using a risk-based approach to eliminate potential failure modes and reduce complexity of the manufacturing process is absolutely necessary,” agreed McElfresh. “Driving out complexity while building in reliability is the best way to improve the overall patient experience. DFM also allows for better management of the product lifecycle and creates a well-planned path to focused process and product improvement.”
Technology Advances
DFM takes into account the latest materials and technologies—the right combination depends on a multitude of factors, including performance specifications, end-use environment, budget constraints, and volume of production. For example, is the product required to be bacteria resistant? With the ever-increasing focus on reducing hospital-acquired infections, one DFM consideration would be selecting laser welding of light-gauge stainless steel for medical and pharmaceutical products. More MDMs are selecting laser welding because traditional welding methods are subject to cracks, crevices, and inclusions where bacteria or fungi could grow, creating potential health risks in hospital settings.
“Laser welding eliminates those dangers,” said Estes. “Precise control of the laser output and precise positioning of the laser beam combine to create a surgically precise, fusion weld. The speed of the laser welding process limits the heat-affected zone, which improves quality. The assist gases are key to supporting the molten metal joint and keeping it free of impurities, such that when it cools and solidifies there is a smooth finish. The precision in the laser welding process requires precision in component manufacturing, as the tolerances for welded corners are as tight as 0.005 inches.”
Additive manufacturing and 3D printing are evolving at a rapid pace, continuously improving in capacity, part size, speed, and materials, including printable polyether ether ketone (PEEK). 3D printing can be used to make complex parts and products that can be manufactured in no other way, especially customized, patient-specific products. Engineers utilizing AM or 3D printing have more design options. Because 3D printing is such a disruptive industry and expected to bring so many improvements to manufacturing in the coming years, some companies in other manufacturing industries are training their engineers to “design to the process”—coming up with innovative new products designed specifically for 3D printing. This puts them at the top of the learning curve, and ready to capture new market opportunities quickly.
As impressive as 3D printing is for making complex parts, perhaps its greatest use so far in the medical device industry is more practical—improving operational efficiency by printing prototypes. This allows the product development team to get their hands on a prototype in a matter of hours rather than days, allowing them to evaluate and validate product designs very quickly, without the expense of putting a part into metal. 3D printing can also be used to make replica instruments or provisionals that are helpful in designing cases for the real instruments.
“Fit and function are key factors of case design, so being able to trial-fit instruments into a case is essential,” said Estes. “Unfortunately, instrument sets from an OEM are hard to come by, so we print our own. Obviously, the mass of a real instrument cannot be replicated, but our plastic versions allow us to evaluate fit in the tray, as well as ease of placement and ease of removal.”
3D printing and other forms of rapid tooling have continued to push the molding envelope. Opportunities to help reduce mold cycle time through conformal cooling have come to the forefront in the last couple of years with the continuing development of metal additive manufacturing machines. “Despite the fact the inserts coming out of these machines still need some post-processing to be ready for molding, they can reduce the total mold build time,” said Scott Kraemer, directing manager of new technology for PTI. “However these machines can easily run around two to five times the cost of a standard computerized numerical control (CNC) machine, so not every shop can afford to add this to their tool box.”
Less material waste (and cost) is an advantage of additive manufacturing over subtractive methods. Rather than cutting the excess away in chip form and recycling the scrap, operators build up only what is needed for each insert. “In some instances, you can grow the inside of the insert with a less dense melt, providing an additional savings of material,” said Kraemer. “Therefore you only pay for what you use, instead of buying a large block and throwing away about a third of it.” However, he noted, not every insert is a good fit for the additive process—some of the more basic, simple parts can still be done faster with subtractive manufacturing.
Growing the inserts with the additive process also makes it easier to accommodate the precise placement of thermocouples (or other inserted objects) with slight-to-moderate contours to get around ejection or other intrusive part areas, which is harder to do with conventional drilling methods. This provides a more robust and consistent processing window.
“Although 3D printing is very useful as a rapid prototyping method for early feedback on designs, we still have a ways to go before 3D printing of plastics replaces traditional manufacturing approaches such as injection molding, when considering part cost at higher volumes,” said Zhang. “A molded part can still be several orders of magnitude less costly than a 3D-printed part at high volumes.”
A tremendous amount of research is being conducted on advanced materials for additive manufacturing, 3D printing, and injection molding. High-tech plastics are engineered to have enough strength and thermal and chemical resistance to replace traditional metal parts (stainless steel and titanium, for example). Medical device manufacturers are utilizing high-temperature materials such as PEEK and polyphenylene sulfide that require mold temperatures up to 400 degrees F and processing temperatures between 600 and 700 degrees F.
“Many of these applications or devices are used in environments or procedures that require the plastics to withstand higher operating temperatures, or replace metal-machined components,” said Budreau. “PTI has a dedicated, high-temperature molding cell with equipment and tooling designed specifically for processing high-temperature resins.”
In another PEEK example, Molded Devices is developing a compounded PEEK containing carbon nanotubes and barium sulfate that will be used for injection-molded spinal screws. “The compound is treated to allow better bone cell adhesion, as well as addressing the patient population that rejects titanium implants,” said Anderson. “There is also a significant cost [reduction] when used as an alternative to the current titanium screws.”
Moving Forward
Many new medical device design and development opportunities are being driven by regulatory interests in human factor considerations (intuitiveness of devices), readmission reduction, never event lists (healthcare delivery quality reporting initiative), and reprocessing of reusable equipment. “Over the past several years, testing and documentation of the user interface and the usability of the product, have become a bigger part of the development process and timeline,” said Anderson.
For well-established or large OEMs, the goal is speeding up navigation within the regulatory process—having the knowledge of current regulatory changes and delivering optimal recommendations based on specific device class and requirements.
“In contrast, small and medium-size clients gain the most by finding ways to optimize their approach to working with FDA,” said Smith. “This often comes down to their predicate device selection. This is critical for design—recognizing the key device characteristics and finding the best fit predicate device or lack thereof will dictate the time and effort required for filing.”
Challenging design-related requests for contract manufacturers include tight timelines, special circumstances tied to clinical builds, unique design characteristics, U.S. Food and Drug Administration snags, and short development cycles for market-ready prototypes. CMs use a variety of materials, techniques, equipment, methods, and know-how to make it happen—including combining solutions in creative ways.
“Many OEMs miss opportunities to improve designs for high-speed manufacturing by not fully understanding the possibilities of hybrid manufacturing,” said McElfresh. “Hybrid manufacturing techniques such as multi-component molding, insert molding, and sintered metal integration can reduce the number of components. Hybrid manufacturing can also eliminate complicated assembly steps such as heat-staking, gluing, bonding, or welding. Often, OEMs fall into the trap of looking at the initial capital investment only and forget to consider the overall reliability, cost savings, and patient risk reduction of hybrid manufacturing approaches.”
With the intense focus on connectivity, the area that may expand the most rapidly will be computing/memory infrastructure for devices, which is also becoming more accessible and simpler to use than ever before. This makes it easier for designers to tap into that infrastructure and create new applications and intelligence for their products. “They no longer need to create the core infrastructure—it’s already there for them to use,” said Anderson.
Key drivers of complexity in medical devices—improved functionality, advanced materials, and miniaturization—continue to create cost pressures on contract manufacturers. Expectations of patients and doctors have never been higher. Medical reimbursements are increasingly tied to the quality of patient outcomes. How quickly can a new product be developed? How valuable is it to shorten the timeline? Human factors are influencing design more than ever before—having a clear picture of user needs, at design inception, will drive down development costs and speed up development time. Technologies now available for rapid prototyping allow designers to iterate faster and at lower cost, yielding design solutions that are more effective from the onset.
“Accelerating development timelines can be one of the greatest challenges for MDMs, and also the biggest competitive advantage,” said Smith. “Relying on trusted partners that can bring your new technology to life quickly will make or break you. It’s really about staking claim early to novel design concepts that ease the delivery model in the form of relaxed cost pressure or increased patient satisfaction.”
Mark Crawford is a full-time freelance business and marketing/communications writer based in Madison, Wis. His clients range from startups to global manufacturing leaders. He also writes a variety of feature articles for regional and national publications and is the author of five books. Contact him at mark.crawford@charter.net.