In part this question can be answered by formal specifications or requirements (“design input” in medical device regulation terms). However the nature of product design is that the design does not prescriptively follow from the design input. We can create more value by exploring the needs, requirements and opportunities interactively while creating and evaluating design concepts. It is only by coming up with a possible design solution that initially hidden questions surface. Embracing this ambiguity in the early phase of the design process leads to better (i.e. more valuable) products.
Here are some common questions we’d like to explore:
Rather than using a list of pass/fail specifications I prefer to define and discuss the parameters that create value (see my blog post on the subject here). Understanding how value is derived from the product allows us to better spot opportunities to increase value, make trade-offs, and reduce costs. Note there will be a compromise required between value to the end user and value to you. An end user will favour lower cost, but selling a low-cost item in small quantities to a dispersed market is not going to be very profitable…
But the “product” under development may not be a final product ready for series production. It may be a looks-like/works-like prototype that allows you to strike a deal with a commercial partner or investor. It may be a breadboard that allows you to run a series of tests to settle technical unknowns. Or it may be a proof-of-concept model that informs the decision if there is an opportunity at all.
All the other questions below are really just addressing specific aspects of this main question.
The design volume is the intended production quantity of the product. Design volume has an enormous impact on feasibility, and on the direction of design choices. When designing for very low volumes (one-off up to perhaps a few tens, as can be the case for certain complex instruments) the cost of parts is usually lower than the cost associated with the design effort itself, and the key imperative is to minimise the time required to complete the design. This means using off-the-shelf parts and modules where possible, even if their specifications are overkill for what is required.
On the other hand, when designing for volumes of tens to hundreds of thousands or millions (which is typically the case for consumables used in diagnostics) the actual unit material, part and production/assembly costs become the most important cost factors, and it pays off to spend time trying to reduce these—after all, every penny saved on one product translates to a thousand pounds at a production volume of 100,000. So for high volumes it can be worthwhile to explore unproven options with cost-saving or value-enhancing potential.
Most instruments have a design volume somewhere between those two extremes, perhaps hundreds to thousands. For these volumes choices are not clear-cut and have to be made on a case-by-case basis.
Many start-ups underestimate the margins they need in order to compete, especially when dealing with high-volume/low-price items. In many industries marginal unit production cost will need to be lower than 10% of end user selling price. As a newcomer to the market you also need a significant value advantage over the incumbent competing product—as a rule of thumb we use a 10x advantage. If your prime competitive advantage is a lower cost, can your product be made for 1% of the selling price of the current alternative?
It might seem that this has little impact on the technical design. But it can be very important! As an example, when I worked at Océ designing copiers these were never directly sold to users. Instead our customers paid a certain fee per page. This meant we had a strong incentive to reduce service costs and toner consumption, and to increase reliability.
In-vitro diagnostics products are frequently sold on the basis of a fixed fee-per-test, either by subscription or by the sales of reagents or test cartridges. The vendors’ ability to produce, install and service at minimal cost allows him to greatly increase the installed base of instruments.
When we worked with Astron Clinica to redesign their skin imaging instrument one major driver was their plan to move from a capital goods model where they sold the camera with supporting software, to a software subscription model where the user rented the software but the camera was supplied free-of-charge.
If you’re looking to design a product to take advantage of your invention you need to be very clear on just what your IP covers, and what freedom to operate you have. Ideally you want to create a nearly impossible product, with your IP being what makes it possible.
Almost all products will need to be CE-marked, but in various industries specific additional regulations apply. The Medical Device Directive applies to healthcare products. ATEX applies to many industrial applications. We need to know what regulations exist for your application.
Especially for medical devices the users (e.g. nurses) are neither buyers, specifiers nor “benefit recipients” (patients).
Many products will need to function as part of a system.
I appreciate these questions can be hard to answer, and in many cases some concept design work needs te be done in order to give specific answers. We’ll be happy to assist.