Read more about the symbiosis of modeling and prototyping (PDF) for designing microscale parts in an article I wrote that was published in MICROmanufacturing Magazine this month, page 33 (Jan/Feb 2010, Volume 3, Issue 1).

You can read the article in the Summer 2009 printed publication or catch it in the online version, Meeting the challenges of micropart design.

The traditional way to make a product cheaper has always been subtraction – in essence, minimizing the size and complexity of a device without sacrificing its performance.  Size and complexity reductions can drive down costs on materials, packaging, and shipping, while also favoring higher-throughput production and the use of disposable parts – an increasingly important consideration in biomedical applications.  With that said, the simpler and smaller approach is not without limitations, and these limitations are being tested now by “hugely small” applications.

In the case of micro-electromechanical systems (MEMS), microfluidic chips, nano-sensing technology, and numerous other scale-intensive fields, reduced size is actually a profound contributor to increased complexity.  And while these innovative fields show tremendous promise for the future, they currently pose costly manufacturing hurdles as a consequence.  The cost of prototyping and manufacturing micro-parts should be carefully weighed when considering whether or not to pursue an otherwise-avoidable micro-approach.  As of now, these costs can quickly consume the benefits of implementing questionable technology since this often requires several iterations of low-volume custom components.  Lab-on-a-chip devices are a good example prone to this paradoxical limbo.  Even a relatively straightforward microfluidic component can require robust interfaces and innovative prototyping and assembly processes to ensure proper functionality.  Before long, the microfluidic system isn’t so “micro” anymore – in size or cost.

So what can designers and our manufacturing comrades do to advance the cost effectiveness of these emerging technologies?  For starters, let’s abandon subtraction and opt for addition;  additional measures to define and achieve design tolerances, additional manufacturing techniques for creating repeatable micron and sub-micron parts, additional design features for ease of alignment during assembly, additional quality assurance measures to assess as-built dimensions, and – most importantly – additional communication between manufacturers and designers for continued success on the field of dreams we now find ourselves playing.

Further advances in microfluidics technology development will educe the most profound breakthroughs in medical diagnostic and therapeutic devices — and ultimately improve patient care. Microfluidics chips enable miniaturization of common macro-scale diagnostic devices down to microliter-level hand-held “lab-on-a-chip” devices. Smaller devices enable use at the point of care, and in certain cases, at home with the patient.

The technical advantages of lab-on-a-chip devices, as commonly known, include smaller sample size, higher throughput, faster analysis, and improved accuracy. Certainly, microfluidics diagnostic devices exist on the market today, but there still is significant untapped potential. For example, recent advances in micro fabrication techniques will enable micro pumps and valves to be located directly on the microfluidic chip, instead of requiring macro-scale components to drive the microfluidic flow.

The challenge for microfluidics is bridging the complex gap between R&D and production. Aside from the basic science employed to monitor the analyte, such as ultrasound or advanced optics, the primary challenge is miniaturizing the surrounding electronics and fluid controls, then integrating them seamlessly with the backbone of the device, the microchip.

For microfluidics devices to be successful, it is imperative for design teams to incorporate experts at all points along the value chain, from concept to design to manufacturing, such that the common mishaps associated with transitioning a design from the micro chip level to the macro world are overcome.