In the development of any new product it is nearly always necessary to first create a prototype or model as there is often some level uncertainty as to whether the new design will actually perform as expected or desired. New product designs often reveal unforeseen problems and conversely unforeseen opportunities.

A prototype is often deployed as part of the product design process to test design variations, test and compare theories as well as validate design performance.

In some situations a series of prototypes will be required as the final iterations begin reveal itself and is modeled for production. Another common strategy is to design, test, evaluate and then progressively improve the design based on analysis of the prototype.

Defining Alpha and Beta level testing

Alpha level testing represents the first round of newly developed hardware or software. When the first round of bugs has been fixed, the product goes into beta test with actual users. For custom software, the customer may be invited into the vendor's facilities for an alpha test to ensure the client's vision has been interpreted properly by the developer. See beta test and testing types.

A test of new or revised hardware or software that is performed by users at their facilities under normal operating conditions. Beta testing follows alpha testing. Vendors of packaged software often offer their customers the opportunity of beta testing new releases, and the beta testing of intricate products such as operating systems can take months. See beta version, alpha test and testing types

In many larger scale product design endeavors it is common to assign each prototype in a series a Greek letter to denote prototypes may be assigned a  letter or number to uniquely identify each prototype. Greek letter to denote the  "Alpha" prototype. Often this iteration is not expected to perform as intended and some amount of failures or issues are anticipated. Subsequent prototyping iterations (Beta, Gamma, etc.) will be expected to continue to improve and reflect the vision of the designer.

Basic prototype categories

There is no general agreement on what constitutes a "prototype" and the word is often used interchangeably with the word "model" which can cause confusion. In general, "prototypes" fall into five basic categories:

a) Proof-of-concept prototype  in electronics often built on a breadboard). A Proof of concept prototype is used to test some aspect of the intended design without attempting to exactly simulate the visual appearance, choice of materials or intended manufacturing process. Such prototypes can be used to "prove" out a potential design approach such as range of motion, mechanics, sensors, architecture, etc. These types of models are often used to identify which design options will not work, or where further development and testing is necessary.

b) Form Study Prototype (Model). This type of prototype will allow designers to explore the basic size, look and feel of a product without simulating the actual function or exact visual appearance of the product. They can help assess ergonomic factors and provide insight into visual aspects of the product's final form. Form Study Prototypes are often hand-carved or machined models from easily sculpted, inexpensive materials (e.g., urethane foam), without representing the intended color, finish, or texture. Due to the materials used, these models are intended for internal decision making and are generally not durable enough or suitable for use by representative users or consumers.

c) User Experience Prototype (Model). A User Experience Model invites active human interaction and is primarily used to support user focused research. While intentionally not addressing possible aesthetic treatments, this type of model does more accurately represent the overall size, proportions, interfaces, and articulation of a promising concept. This type of model allows early assessment of how a potential user interacts with various elements, motions, and actions of a concept which define the initial use scenario and overall user experience. As these models are fully intended to be used and handled, more robust construction is key. Materials typically include plywood, REN shape, RP processes and CNC machined components. Construction of user experience models is typically driven by preliminary CAID/CAD which may be constructed from scratch or with methods such as industrial CT scanning.

d) Visual Prototype (Model) will capture the intended design aesthetic and simulate the appearance, color and surface textures of the intended product but will not actually embody the function(s) of the final product. These models will be suitable for use in market research, executive reviews and approval, packaging mock-ups, and photo shoots for sales literature.

e) Functional Prototype (Model) (also called a working prototype) will, to the greatest extent practical, attempt to simulate the final design, aesthetics, materials and functionality of the intended design. The functional prototype may be reduced in size (scaled down) in order to reduce costs. The construction of a fully working full-scale prototype and the ultimate test of concept, is the engineers' final check for design flaws and allows last-minute improvements to be made before larger production runs are ordered.

Differences between a prototype and a production design

In general, prototypes will differ from the final production variant in three fundamental ways:

Materials. Production materials may require manufacturing processes involving higher capital costs than what is practical for prototyping. Instead, engineers or prototyping specialists will attempt to substitute materials with properties that simulate the intended final material.

Processes. Often expensive and time consuming unique tooling is required to fabricate a custom design. Prototypes will often compromise by using more variable processes, repeatable or controlled methods; substandard, inefficient, or substandard technology sources; or insufficient testing for technology maturity.

Lower fidelity. Final production designs often require extensive effort to capture high volume manufacturing detail. Such detail is generally unwarranted for prototypes as some refinement to the design is to be expected. Often prototypes are built using very limited engineering detail as compared to final production intent, which often uses statistical process controls and rigorous testing.

limitations of prototypes

It is important to realize that by their very definition, prototypes should be recognized for what they are, a temporary and often fragile solution barely representing the final article. They are often wobbly cobbled together ugly cousins of their polished and market ready cousins but without them projects would simply drag on and on!

Most product development endeavors can be conquered with readily available materials and services both here and abroad. With the advent of desktop Stereo logography the "idea to reality" cycle has never been so painless.

Electronics prototyping

Just a decade or so  ago electronics engineers were limited to very primitive means of constructing prototype circuits. The big budget firms had the luxury of direct to P.C.B. prototyping but those on much smaller budgets were forced to deploy wire-wrap connected vector boards. I still have several just to remind myself what it was like to be in the dark ages!

Today's modern electronics designer often begins his or her design prototype with a pre-simulated based P.C.B. that directly ships to a component stuffer that can stuff and pre-validate the P.C.B assembly the next day.

The proliferation of quick-turn P.C.B.  fabrication companies and quick-turn P.C.B.  assembly houses has enabled the concepts of rapid prototyping to be applied to electronic circuit design. It is now possible, even with the smallest passive components and largest fine-pitch packages, to have boards fabricated and parts assembled in a matter of days.

Vorelco is old school when it comes to prototyping. Although there is no shortage of computer modeling tools out there we prefer to combine the power of FMEA with good old fashioned hand and machine built prototypes. Our prototypes look, feel and function just like a production sample and by not relying solely upon computer modeling we can find design problems early enough to avoid costly tooling changes. Design remediation at the prototype level is far less painful than design remediation at the tooling or mold making level! A functional, safe and reliable product begins with comprehensive prototyping, testing and more testing.

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