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:

Define Clear Objectives and Scope:

Before starting any FEA or Simulation project, it is essential to define clear objectives and scope. This involves identifying the specific questions that need to be answered, such as whether a device will perform as expected under specific conditions, whether a design change will improve device performance, or whether a device is safe and reliable for patient use? Defining the scope of the project ensures that the simulation is focused and tailored to the specific requirements of the device.

Select Appropriate Simulation Software:

Selecting the appropriate simulation software is critical to the success of FEA and simulation in medical device development. Different simulation software packages are available, each with its own strengths and limitations. Usually, they can be tailored to suit a specific analysis, ranging from CFD, solid mechanics, thermal propagation and many more. It is essential to select the software that best suits the specific application and the desired outcomes of the simulation. Design consultancies with experience in medical device development can provide valuable insights into selecting the appropriate software for the project.

Medical Device Design Engineer conducting finite element analysis study on autoinjector medical device component (FEA)

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.

Optimize Meshing Techniques:

Meshing is the process of dividing a complex geometry into a finite number of simpler, interconnected elements. Meshing is critical to the accuracy and efficiency of FEA and simulation in medical device development. The mesh density, element type, and element size all affect the accuracy of the simulation results. Optimal meshing techniques are essential to minimize computation time, maximize accuracy, and ensure that the simulation reflects the real-world behaviour of the medical device.

Interpret and Analyse Simulation Results:

Interpretation and analysis of simulation results is essential to extract valuable insights from the simulation. Interpretation involves understanding the behaviour of the medical device under different conditions, while analysis involves identifying potential design improvements or issues that need to be addressed. Experienced design consultancies can provide valuable insights into interpreting and analysing simulation results, helping make informed design decisions.

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.

Danny Morris - Senior Medical Device Design Development Engineer & Health & Safety Manager at Haughton Design Danny Morris 24 August 2023

Share

Get in Touch with Danny Morris

Senior Design Development Engineer

Danny graduated from Aston University with a BSc degree in Industrial Product Design. Prior to HD, Danny worked in engineering roles, designing products varying from plastic vehicle bodies to sheet metal fabrication, gaining valuable experience of manufacture in the production environment. Within HD, Danny is an advocate for developing skills and capabilities within the team to broaden HD’s services. Danny also assists with project management activities and is our Mental Health First Aider.

Get In Touch

Our latest insights

Latest Posts

How Can Collaborating with the NHS Improve Medical Device Innovation?

Read More...

Digital Devices & Trust: Why Do We Trust Them More Than Their Non-Digital Counterparts?

Read More...

Share