Medical device design: Getting it right first time

Barry Warden, managing director, Wideblue explains some key considerations for medical device design, including on a recent project.

Over the past 16 years we have worked with scores of medical device manufacturers on helping them bring their innovations to market. During this time two things have stood out -- the importance of prototyping and testing.

Medical device design and manufacture is highly regulated and quite rightly so. A fault in design or construction can quite literally mean life or death.

There are several questions to consider:

• Is there a market need for the device, does it solve a medical/clinical need? 
• What is its likely impact on the market and has anyone developed anything similar? 
• Is the IP properly protected? 
• Patient safety and comfort in the use of the product 
• What is the regulatory framework and what certifications govern the production, marketing and use of the device? 
• Will manufacture be low, medium or high volume.  This will determine the nature of the supply chain and the selection of components and materials. 
• Testing, traceability, validation and quality assurance.

Once the initial designs and specifications have been chosen production of prototypes can begin. Fortunately, with the advent of technologies such as 3D printing and Selective Laser Sintering working models can be produced cost-effectively to be as close as possible to the real thing. Be prepared to build several iterations of the device. Ideas which look good on the CAD system can fail when in the hands of potential users. In many cases it is not just the functionality of the device that is important, but the look and feel is as well; the patient must feel comfortable using the device.

Rapid prototyping is now an established process where a full-scale model of the device or product is manufactured out of a polymeric material bound together to make a solid object, usually in a very short timescale. While a plastic version of a product that is designed to be make out of metal may not have the same properties but the fact that a designer is able to hold an exact sized article goes a long way to verifying the design. Rapid prototyping is an important tool and is now available in various guises and formats, so picking one to meet any budget is possible.

Having a physical product to try out is a great advantage in gathering feedback from others and your market research. Even the best designers make mistakes and the sooner any issues are uncovered the better. Even the smallest mistake when transferred into a production environment can be costly in terms of rework or retooling.

A prime example of a project where prototyping was essential was the development of an automatic surface disinfection system for use in hospitals.

Entitled Project LUSS (LED based Ultra-Violet exposure for Safe Surfaces) the idea was to create an economical solution to combat COVID-19 infections in public spaces, with the added benefit of also disinfecting other viruses and bacteria such as MRSA and C.diff.

Funded by Innovate UK, the project brought together Microlink Devices and the Compound Semiconductor Applications Catapult Consortium with Wideblue as the product designer.

The device consists of a mechanical arm which automatically sweeps across the surface (such as a door panel) after each use and kill viruses using a powerful ultraviolet-c light. This is intended to remove the need for frequent manual cleaning of hospital door panels and other surfaces which come into contact with the public.

A key part of the project was the production of several prototypes which could be tested in a hospital setting. Several iterations of the design were tested until a final version was chosen. 

In conclusion, prototyping is now easy to carry out and the benefits of creating a realistic model far outweigh the associated costs. Normally, rapid prototype models require only a CAD file and because such files can be sent to a manufacturing company via email, your design can be sent to any company you choose regardless of where they are in the world. 

Creating a prototype product will give you the ability to visualise your product in a way that no computer program or series of sketches can. Prototyping will help you enhance your product’s attributes and iron out any issues before you commit to a final design.

Wideblue will be exhibiting at the Med-Tech Innovation Expo at the NEC on 7-8 June 2023 in Hall 2 on stand E52. Register for FREE at www.med-techexpo.com