The use of computer-based simulation technologies has been popular for many years in industries such as the automotive and aerospace sectors. In the medical device field, however, these tools are still relatively new. One of the reasons for this is the fact that the medical device industry is so heavily regulated, with the US FDA requiring that all medical tools undergo rigorous tests during the product development stage.
Manufacturers are now realising that there are profits to be made if they can successfully incorporate simulation into their design process and use it to fulfill FDA requirements.
Very simply, simulation software allows engineers to design products right on their computer screen. By factoring in all of the specifications they want and the conditions in which the products will be employed, manufacturers can use the technology as a complement to FDA-mandated tests.
This virtual complement to testing a physical product has numerous benefits to manufacturers. Not least of these is the ability to streamline the manufacturing process by detecting problems with the design during the trial and error of the simulation phase.
"The biggest advantage that manufacturers get out of simulation software is that as they see problems, they can catch them right at the very initial design or analysis stage and make the corrections there," says Dennis Sieminski, director of sales and marketing at NEi Software. The California-based software company sells finite element analysis (REA) software to the medical industry.
"It helps improve the quality of products and it allows companies to be more innovative in the sense that they can try different ideas. They can try different variations of the product and see what the results are going to be as far as the test loads."
As the medical device industry is under tremendous pressure to release only the most innovative of products, this cheap trial and error virtual testing is of great benefit. When engineers use computer-based simulation programmes, they are able to save time because the technology eliminates the process of making numerous prototypes, breaking them and starting all over again.
When trying to remain competitive in the current marketplace, this process takes too long to make it a feasible option. When manufacturers save time during their production cycle, they ultimately save money.
"You could potentially save manufacturers a lot of money if you prevent them from manufacturing a design that is not going to meet their specifications," says Bill Kelly of Mechanical Solutions, a company that carries structural analysis consulting for medical device manufacturers.
As the firm's principal engineer, Kelly has used a number of simulation products, including NEi software. "If medical device manufacturers come to us and have us analyse a specific design and we tell them it's going to break at some load level that they're unhappy with, then they wouldn't have to actually make those parts and test them," he explains.
"That's going to save them a lot of money, especially if it's a complicated part. Not to mention how much quicker you can get to your final design. When you make your parts, test them, and they break so you have to go back to square one, you lose a lot of valuable time."
Although saving money is certainly important to any company's bottom line, Vince Adams, the product manager of simulation products at SolidWorks, warns against neglecting innovation in the pursuit of keeping costs down.
"The problem with that mentality is you may have got the design right, but you don't know if it was the best design," he explains. "When you're fighting to take pennies and dollars off your product, money can be saved by taking time to come up with a cheaper design – or a design that uses better materials, that can be produced less expensively. More importantly, it is possible to work with concepts that you may have never taken to test because testing is so expensive in medical products."
He adds: "Using the tool to evaluate options you would probably not authorise for production, or even prototyping, is one of the huge benefits of simulation. It gives you the chance to explore things you never would have, which is essentially the crux of innovation."
Simulation to production
There is nothing virtual about the innovations that have been created as a result of using simulation in developing medical devices. Numerous companies have used the technology to manufacture life-saving products:
Luminous Medical used SolidWork's COSMOSFloWorks software to design a blood glucose monitor that is able to automatically draw blood samples from a patient's IV system, analyse the blood and return it to the patient's body. By using this simulation technology while designing the Luminous Medical Glucose Measurement System, the company was able to predict – and improve upon – blood and saline movement through the product. As a result, the Luminous system has helped to improve the care of terminally ill patients while reducing the time that nurses spend drawing blood.
NuLens developed a prosthetic adjustable lens used to improve the eyesight of patients that have undergone cataract surgery, by using NEi's Nastran simulation software. Previously, patients with cataracts would have surgery that would correct the cloudiness from their vision, only to be left with the inability to focus on objects close to them. By designing the product on simulation software, the company was able to create a lens that can mimic the functions of the human eye.
Software sold by ANSYS was used by the Pathogen Control Engineering Group at the University of Leeds, which conducts research on the spread of airborne pathogens. In response to the rise of infections contracted and spread by hospital ventilation systems, the group began using simulation software to find a solution. By simulating the flow of air and the infectious contagions that could be present, the researchers were able to create a cost-effective solution to combating infections like influenza and tuberculosis.
Hearing instrument provider GN ReSound uses simulation software sold by Dassault Systèmes to design its hearing aids. Simulation allows engineers at GN ReSound to make virtual models of their hearing aids that are run through virtual vibration and sound pressure stresses, which helps the company create a product that can withstand real-world conditions.
Despite the accomplishments of manufacturers thanks to simulation software, there are still some limitations. Although it is easy to predict what will happen with the design of an automobile or an airplane, when biology is involved there is less certainty. Scientists, however, are always conducting research in this area in order to understand how the human body will respond to medical devices. As the biological understanding increases, engineers will be more confident as they design products for the medical field.
"The more we know about the biology, the better we can make the simulation tools and people will rely on and trust them through this design process," says Shankar Sundaram, vice president of Biomedical Technology at CFD Research Corporation, a company that creates engineering simulation technologies for industries such as biomedical, defence and aerospace.
As biological research develops so too will simulation software. By using this trial and error technology to stress test new products, design will be stretched to the far parameters of today's scientific ability.