The Proof of Concept Phase is between the design phase and the preproduction phase. This is the process where we vet the science. We loosely fabricate the first unit with as many off-the-shelf components as possible to limit development cost.
The key in the Discovery and Prototype Phase is to find the fastest and least expensive path to failure. In other words, what is the smallest and least expensive experiment to determine if the approach will pass or fail? The critical question to answer is "Does this approach have all the key elements for a successful solution?"
The next phase develops a working prototype. The team continues to refine, condense, retool, and shrink the prototype to approach the final product. We take the functionality of the off-the-shelf components and customize the working prototype to prepare for the preproduction phase. Mechanical parts are fabricated with 3D printing and some of the software gets refined to be more efficient. Sometimes this process involves designing printed circuit boards and other adjustments to hardware and software to shrink the final product by eliminating unneeded parts.
After we have a fully functional prototype and the product is such that it will need industrial design for the outside of the product for mass production, we bring in our industrial design partner.
Prototyping is an important transition in two phases of the process: as a testing and verification step between discovery and design, and as a more refined version in preproduction completion to the engineering phase.