Paul Dunleavy, Senior Vice President of Engineering

In my previous blog, “Cogmedix Medical Device Development Process – How to Innovate and Maintain Compliance”, I reviewed Cogmedix’s product development process and provided recommendations on fast-tracking innovation within a rigorous compliant stage gate process.  

rapid prototyping medical deviceEstablishing proof of concept and innovation prior to entering Design Controls through fast design iterations of test beds and engineering models may be a preferred strategy depending on the technology maturity and business goals. All product requirements are not typically identified or even understood during the early stage of product development or starting a new business. Test beds or engineering model prototypes allow valuable bench top testing that can provide a better understanding of product performance goals and requirements. These prototypes can be tested and rapidly iterated to hone in on the requirements. All functional components and subassemblies can be assembled on a single flat plate such as in the case of a test bed, or integrated into a prototype frame such as in the case of engineering model prototypes.

Make sure to schedule test bed and engineering model development and fabrication into your project plan. When expediting prototype lead times, identify short lead time manufacturing technologies and suppliers who can provide quality parts to de-risk the project. Below are some recommended strategies per commodity:

  • Machined Parts – Minimize tolerance requirements where possible and plan two weeks as a good expedited prototype lead time. Some metal parts may be 3D printed depending on the part’s requirements and geometry. In this case, the expected lead time may be even shorter.
  • Sheet Metal – Minimize tolerance requirements where possible and keep to simple geometry for covers, frames and brackets. Plan four weeks as a good expedited prototype lead time. Other fast prototyping options may be erector set frames such as 80/20 and Rexroth.
  • Plastic Parts – 3D printers are best for parts that are reasonably priced and good quality. Expect one week as a good expedited 3D printed lead time. Machining plastic parts is a more expensive option and is typically a longer lead option. Coghlin Companies has two types of 3D printers and is capable of fabricating soft durometer parts and strong structural plastic components.
  • Electronic Components – Development kits can help jump start development. Many suppliers such as Digikey and Mouser Electronics have stock availabilities and next day shipping.
  • Printed Circuit Board Assemblies – Plan expedited fabrication and assembly of PCBA of three to five day lead times.
  • Optics Parts – When possible, select off-the-shelf components for proof of concept models from online suppliers such as ThorLabs and Edmund Optics. Custom optics are costly with long lead times and may go through multiple iterations.
  • Hardware Parts – Online hardware suppliers such as McMaster-Carr often have inventory that is able to ship next day.

Entering Design Controls too early without a clear understanding of requirements will force unplanned design iterations later in the development process, potentially resulting in unexpected budget overruns and schedule delays. Reducing program risk by demonstrating feasibility early in the project is best done through fast design iteration of test beds and engineering models prior to entering Design Controls. Cogmedix has the expertise and capabilities to assist our customers at any phase of the product development process with exceptional quality, compliance and customer experience.