How to Avoid Design Mistakes: EVT, DVT, and PVT
Product Design in 2022
Electronic and plastics manufacturing is growing globally at a rapid rate. With a growing product manufacturing industry comes updates to modern product design thinking. Many philosophies are attached to product design, but Jaycon Systems has succeeded in multiple, well-defined, conventional product design stages. This allows for less confusion, more consistent and transparent communication, and a streamlined, quick, cost-effective design process. Check out the video below for a breakdown.
In this article, we will cover going from an idea to a Product Requirements Document, then building a proof of concept, going through a series of necessary validation tests (EVT, DVT, PVT), and finally transitioning to mass production. We'll also discuss common issues in the product design process and how to manage them.
Cutting Corners Won't Cut Costs
Skipping steps during an internal effort like design can be tempting. However, missing even one step in the product design process can have dire consequences. A single working prototype could spell disaster for a product by diving into mass production. As we will find out, each stage of product design helps verify the quality of both the product and production. This can save money and time over time. If there is one lesson to be learned about product design: Do not rush the product design process.
Each stage of product design has a set of conditions engineers can establish. Until those conditions are met, product designers must not advance in the process. There is no point in mass production if the design isn't working. These cycles start with an idea and a set of specifications for the product's function and form.
Design Process Steps
FROM IDEA TO PRODUCT REQUIREMENTS, DOCUMENT
Often, someone with a product idea will only have a drawing on a napkin and some starting points on how that drawing could come to life. From there, conversations between industrial designers, engineers, and the client can lead to a more precise industrial design and visual design language for the product. This is a great time to nail down the aesthetics and finalize the required specifications of a product. The intended function of any product will dictate things as fundamental as the shape, size, materials used, and components sourcing. At this point of the product design process, creators should have a PRD (Product Requirements Document) detailing what a product should do. Here's a simple PRD template we made for entrepreneurs. Once the visual design and target specifications have been defined, physical proof of concept can help stakeholders bring a product to market.
BUILDING A PROOF OF CONCEPT
Early-stage, fully functioning prototype costs are often astronomical because optimizing cost per unit is not a primary priority. Cost per unit only matters in the later steps of the product design process. For example, calculating the cost of the original iPhone proof of concept in 2006 would mean calculating the man hours and resources spent making and remaking it, research and development adapted from other products by the same company, and custom components ordered over an extended period. From this perspective, the prototype and testing stage can cost thousands or even millions. Despite the cost, prototyping has value. A complete design ready for mass production requires many steps, though.
Proofs of concept are the first step toward a finished product. Engineers use these proofs to explore how the final version would work or feel. Before prototyping and testing can begin, engineers manufacture a very low-quantity production run. Under ten units can help test key product functions and features and gain confidence in the manufacturing processes. This is also a perfect opportunity to test multiple variants at low-production runs to record any imperfections and land on a successful design. It is important to note that proof of concept is often low quality compared to a finished product. The product is not ready to ship at this point, but it is getting closer. This is not something you would take and sell to anyone. Instead, manufacturers can take this to demonstrate what you're looking for.
Proof of concepts can be as simple as 3D-printed or clay-formed models showing the physical aspects of a product. The goal is to communicate the function and form of your idea. The product team cannot move forward if the design fails at this stage. Instead, they must go back to the drawing board and redesign the product to avoid the same problems later. With a more well-defined feel and function, a product team can finalize part lists, model files, and aesthetic design. Once product documents are in order, a team can reach out to a contract manufacturer, and the process of the "3 VTs" can begin.
WHAT IS AN EVT?
EVT (Engineering Validation Testing) is a stage of product design that aims to finalize the product's function and form. EVT involves making a product with materials intended for the final version and creating something that looks like and works like the final version of the product. At this stage, prototypes should meet all functional requirements of the PRD (Product Requirement Document). We should be looking at a fully realized 1-of-1 product. EVT is critical for manufacturing electronic devices as technology is miniaturized and designed to fit specific physical parameters. Engineers and assemblers work together to ensure this step runs smoothly, as this is often the first time a finished product is put together.
As testing continues, units often fail for various reasons unforeseen in the proof of concept stage. This step is when engineers finalize delicate factors in production like hand-soldering and assembly or testing glues and coatings. EVT usually requires only a small production run of 20–1000, depending on what is being made and the quality standards set. If any significant design flaws are uncovered after initial functional testing and analysis, the process repeats until a final working product can be made. The result? A fully available and testable product made from materials intended for the final product and designed for manufacturing. Once that is accomplished, the product team must apply rigorous testing to completed units of the product and the tools used to make them. After all, what good is a single final product?
WHAT IS A DVT?
DVT (Design Validation Testing) is a stage of product design testing that aims to arrive at one production-ready design. DVT is all about improving tools and techniques to achieve more consistent production and ensures products meet cosmetic and environmental requirements using both mass production tools and parts.
Depending on the device or product being made, and the quality standards set for them, DVT may require anywhere from 50 to 2,000 units manufactured. Whatever your production numbers are, the goal is to scale slowly as you move through the phases of product design. First, products are put through rigorous testing, measuring damage to drop damage, extreme temperature changes, corrosion, water, and, if applicable, battery testing. This step is crucial for products needing regulatory certifications from national and international bodies like the FCC or UL. This is the final step before making units that are suitable for sale. At the end of DVT, your team will have corrected any underlying issues in the product's design. Successful DVT also means your team is now making products on mass-production-ready lines with mass-production-ready tools. Sometimes this means making the leap from aluminum molds to steel.
At this point in the production process, it is not as wise to test alternate production lines because the increasing volumes can mean increased testing costs. Trying alternated production lines means testing each variation for errors and manufacturing as many as 2000 of each alternate design. Variations in structure and function should be addressed earlier in the product design process. The goal is to confirm the final design. Once that is done, the next step will be preparing to scale.
WHAT IS A PVT?
Also called an MVT (Manufacturing Validation Testing), PVT (Product Validation Testing) centers around testing manufacturing capabilities at full speed and assuring quality at higher and higher volumes. In the product validation testing stage, engineers design and build quality control systems based on common manufacturing errors spotted in these early runs.
A product validation test often measures the quality of finished products made at full production speed. Usually, this means making 1,000 or more units of a product and counting for functional and cosmetic imperfections, as well as irregularities within the manufacturing process, like operator training level, line speed, and line yield. Engineers then recommend and apply changes to the manufacturing process to improve yield and quality. This process can take anywhere from a few weeks to a few months, depending on production times.
These printed circuit boards are some of the first to count toward a production run. This is because they are fully assembled, and their predecessors have been checked for faults and controlled for quality.
Products made during these final tests often become some of the first units sold as part of the initial production run. This stage is the last opportunity to correct or improve the production process before ramping up to faster high-volume runs. This is not the time to change your product's design and its decorative and functional features. That has already been done in previous stages.
Common Issues in Product Design
Product Design is a well-established process with well-established stages. With that comes common issues that clever product designers and manufacturers can anticipate.
Establish expectations early. Establish times to communicate and recurring meetings with set agendas and lengths. Most contract manufacturers and clients dislike making nightly calls or having daily arguments with outside stakeholders. Keep communication consistent, transparent, and detailed, but establish reasonable expectations on how both parties will interact. What do you need out of your contract manufacturer? What do they need out of you? The earlier you answer these questions, the better.
Do not ignore errors and mistakes; correct them. Product design is an iterative and comprehensive process where a team can root out even the slightest imperfections to improve the final product. Correcting mistakes in the product design or the manufacturing process early means a better final product and faster higher-volume production. In addition, minor changes to the manufacturing process, such as alternate coatings or curing parameters, can improve a product drastically.
Higher standards can lead to longer testing phases. This is not bad, but it can come at a cost. In addition, cosmetic blemishes are some of the most common imperfections in high-volume consumer product manufacturing. Truly perfecting the look of your product could take weeks and thousands of additional units. But in the long run, it could save you money.
Anticipate component delays. There is often at least one vendor unable to reach expected yields, and because they cannot produce at the quantities promised, the entire operation halts. A single component can stop a product launch, mainly if that part can only be sourced from one supplier or manufacturer. In today's competitive global economy, issues like high lead times and out-of-stock electronic components have become even more common. Being armed with accurate and frequently updated timelines from manufacturers can help you anticipate delays before they happen. In addition, contract manufacturers often try to source from multiple companies to avoid extreme lead times.
Keep your manufacturing processes updated. Products can involve dozens of constantly involving connections between vendors, contract manufacturers, a design team, and much more. Changes in product parameters and specifications, tool maintenance, material and component sourcing, etc., can all influence the quality of a product and the speed at which it is manufactured. Controlling and accounting for these factors can help create a consistent product in a changing environment.
How Do I Transition to Mass Production?
PVT often blends slowly into full-scale production. This ramp-up means scaling up the number of assembly lines and increasing the number of trained workers to increase production volume. Ramping up can also mean changing the design based on real-world use and sourcing parts and tools from additional vendors as your operation grows. Of course, sustaining high production volume becomes an entirely different conversation. Companies can apply high-quality product design principles to help make manufacturing smoother later.
Product design is an integral part of winning product development. It's important not to skip steps and to be prepared with a plan. However, product design and mass production after it are much easier with some help. Jaycon Systems offers a full suite of product design and manufacturing services, specializing in consumer and medical devices. Our in-house white glove services help every step of the way, and our global network provides access to experienced engineering teams and a variety of manufacturing methods. If your company wants to make a product a reality, reach out to us for a no-cost, no-commitment quote.
