What is Rapid Application Development? (RAD) | Analysis and Design | FAQ

Prototyping is a crucial part of the product development process, but traditionally, it has been a bottleneck.

Product designers and engineers would create makeshift proof-of-concept models with basic tools, but producing functional prototypes and production-quality parts often required the same processes as finished products. Traditional manufacturing processes like injection molding or CNC require costly tooling and setup, which makes low-volume, custom prototypes prohibitively expensive.

Rapid prototyping helps companies turn ideas into realistic proofs of concept, advances these concepts to high-fidelity prototypes that look and work like final products, and guides products through a series of validation stages toward mass production.

With rapid prototyping, designers and engineers can create prototypes directly from CAD data faster than ever before, and execute quick and frequent revisions of their designs based on real world testing and feedback.

In this guide, you’ll learn how rapid prototyping fits into the product development process, its applications, and what rapid prototyping tools are available to today’s product design teams.

Rapid prototyping is the group of techniques used to quickly fabricate a scale model of a physical part or assembly using three-dimensional computer-aided design (CAD) data. Because these parts or assemblies are usually constructed using additive fabrication techniques as opposed to traditional subtractive methods, the phrase has become synonymous with additive manufacturing and 3D printing.

Additive manufacturing is a natural match for prototyping. It provides almost unlimited form freedom, doesn’t require tooling, and can produce parts with mechanical properties closely matching various materials made with traditional manufacturing methods. 3D printing technologies have been around since the 1980s, but their high cost and complexity mostly limited use to large corporations, or forced smaller companies to outsource production to specialized services, waiting weeks between subsequent iterations.

The advent of desktop and benchtop 3D printing has changed this status quo and inspired a groundswell of adoption that shows no sign of stopping. With in-house 3D printing, engineers and designers can quickly iterate between digital designs and physical prototypes. It is now possible to create prototypes within a day and carry out multiple iterations of design, size, shape, or assembly based on results of real-life testing and analysis. Ultimately, the rapid prototyping process helps companies get better products to market faster than their competition.

Rapid prototyping elevates initial ideas to low-risk concept explorations that look like real products in no time. It allows designers to go beyond virtual visualization, making it easier to understand the look and feel of the design, and compare concepts side by side.

Physical models empower designers to share their concepts with colleagues, clients, and collaborators to convey ideas in ways not possible by merely visualizing designs on screen. Rapid prototyping facilitates the clear, actionable user feedback that is essential for creators to understand user needs and then refine and improve their designs.

Design is always an iterative process requiring multiple rounds of testing, evaluation, and refinement before getting to a final product. Rapid prototyping with 3D printing provides the flexibility to create more realistic prototypes faster and implement changes instantly, elevating this crucial trial and error process.

A good model is a 24-hour design cycle: design during work, 3D print prototype parts overnight, clean and test the next day, tweak the design, then repeat.

With 3D printing, there’s no need for costly tooling and setup; the same equipment can be used to produce different geometries. In-house prototyping eliminates the high costs and lead time associated with outsourcing.

In product design and manufacturing, finding and fixing design flaws early can help companies avoid costly design revisions and tooling changes down the road.

Rapid prototyping allows engineers to thoroughly test prototypes that look and perform like final products, reducing the risks of usability and manufacturability issues before moving into production.

Thanks to a variety of available technologies and materials, rapid prototyping with 3D printing supports designers and engineers throughout product development, from initial concept models to engineering, validation, and production.

Concept models or proof-of-concept (POC) prototypes help product designers validate ideas and assumptions and test a product’s viability. Physical concept models can demonstrate an idea to stakeholders, create discussion, and drive acceptance or rejection using low-risk concept explorations.

The key to successful concept modeling is speed; designers need to generate a wealth of ideas, before building and evaluating physical models. At this stage, usability and quality are of less importance and teams rely on off-the-shelf parts as much as possible.

3D printers are ideal tools to support concept modeling. They provide unmatched turnaround time to convert a computer file into a physical prototype, allowing designers to test more concepts, faster. In contrast with the majority of workshop and manufacturing tools, desktop 3D printers are office-friendly, sparing the need for a dedicated space.

As the product moves into the subsequent stages, details become increasingly important. 3D printing allows engineers to create high-fidelity prototypes that accurately represent the finished product. This makes it easier to verify the design, fit, function, and manufacturability before investing in expensive tooling and moving into production, when the time and cost to make change becomes increasingly prohibitive.

Advanced 3D printing materials can closely match the look, feel, and material characteristics of parts produced with traditional manufacturing processes such as injection molding. Various materials can simulate parts with fine details and textures, smooth and low-friction surfaces, rigid and robust housings, or soft-touch and clear components. 3D printed parts can be finished with secondary processes like sanding, polishing, painting, or electroplating to replicate any visual attribute of a final part, as well as machined to create assemblies from multiple parts and materials.

Engineering prototypes require extensive functional and usability testing to see how a part or assembly will function when subjected to stresses and conditions of in-field use. 3D printing offers engineering plastics for high-performance prototypes that can withstand thermal, chemical, and mechanical stress. The technology also provides an efficient solution for creating custom test fixtures to simplify functional testing and certification by gathering consistent data.

Having a great prototype is only half the battle; a design has to be repeatedly and economically manufacturable to become a successful final product. Design for manufacturability (DFM) balances the aesthetics and functionality of the design while maintaining the requirements of the end product. DFM facilitates the manufacturing process to reduce the manufacturing costs and keep the cost per part below the required level.

Rapid prototyping allows engineers to create small-batch runs, one-off custom solutions, and sub-assemblies for engineering and design validation (EVT and DVT) builds to test manufacturability.

3D printing makes it easier to test tolerances with the actual manufacturing process in mind, and to conduct comprehensive in-house and field testing before moving into mass production. 3D printed parts also support production, with prototyping tools, molds, jigs, and fixtures for the production line.

With 3D printing, design doesn’t have to end when production begins. Rapid prototyping tools allow designers and engineers to continuously improve products, and respond quickly and effectively to issues on the line with jigs and fixtures that enhance assembly or QA processes.