Incorporating FEA and simulation into the medical device development process requires careful planning and execution. Senior Design Engineer, Danny, shares some of the best practices for successful FEA and simulation in medical device development:
Finite Element Analysis (FEA) and simulation are powerful tools that have revolutionized the field of medical device development. They allow designers and engineers to simulate and optimize device performance under various conditions, reducing the need for costly and time-consuming physical testing. Here are some tips and best practices for incorporating FEA & Simulation into your medical device development:
Perform an Initial Hand Calculation:
An initial hand calculation is beneficial when trying to determine that your FEA setup is correct. For example, you have designed a safety cap for an auto-injector and estimated the removal force to be 15 Newtons. However, your FEA study shows 100 Newtons. As this is significantly different from the hand calculation, there may be an issue with the set up. Maybe the material properties are incorrect making the component much more rigid in the study? Or, it could highlight an issue with the design! Either way it’s good to be able to refer to a hand calculation as a benchmark to rule out any potential set-up errors and validate outcomes.
Simplify the Study:
Where possible it is beneficial to determine what areas of the design can be simplified or even removed from the study altogether. Although this takes some additional time during set up, the reduced computation time at the end more than makes up for it. Referring to our auto-injector example, if we wanted to test the firing mechanism, we may want to remove detailed features such as the grip indentations on the outer casing, or even the outer casing all together if it isn’t detrimental to the firing mechanism performance. The challenge with study simplification is to successfully determine what can be removed from the set up without impacting the results.
Validate Simulation Results with Experimental Data:
Validation of simulation results with experimental data is critical to ensure that the simulation accurately reflects the real-world behaviour of the medical device. A typical example of experimental data would be Instead of setting up the full assembly from the start, to isolate components and test incrementally and ensure you are getting the expected results. This forms the basis of your experimental data. Following this you can build up the complexity of the study by adding more components and re-running the analysis. Going back to our auto injector example, if you wanted to determine the amount of stress caused from the activation of the spring, you could initially apply the force to just the spring housing. If this looks representative, you can then add the outer casing to the set up and re-run the study. This would then show how the force transfers through the spring housing as well as the outer case. This gives you confidence that the study is representative to real world scenarios but also allows you to isolate and resolve set up issues as you build up the complexity of the analysis.
Integrate FEA and Simulation into Design Verification and Validation:
Integrating FEA and simulation into the overall design verification and validation process can be critical to ensure that the medical device meets the desired performance and safety requirements, as it may highlight issues that are not visible through physical testing alone. Simulation can be used to verify the design and validate it against the desired outcomes. By integrating FEA and simulation into the design verification and validation process, medical device developers can reduce the need for iterative physical testing, reduce the risk of failures, and accelerate time to market.
FEA and simulation have become essential tools in medical device development, providing a faster, more accurate, and more cost-effective approach to device design and optimization. By following these best practices, you can maximize the benefits of FEA and simulation, ensuring that the medical device meets the desired performance, safety, and regulatory requirements.