A prototype is an early sample or model built to test a concept or process or to act as a thing to be replicated or learned from.

It is a term used in a variety of contexts, including semantics, design, electronics, and software programming. A prototype is designed to test and trial a new design to enhance precision by system analysts and users. Prototyping serves to provide specifications for a real, working system rather than a theoretical one.

Prototyping is a method used by designers to acquire feedback from users about future designs.
Prototypes are used to revise the design for the purposes of reducing costs through optimization and refinement. A prototype is a scaled model.

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 accuracy/quality. 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.

Advantages of prototyping
May provide the proof of concept necessary to attract funding Early visibility of the prototype gives users an idea of what the final system looks like Encourages active participation among users and producer Enables a higher output for user Cost effective (Development costs reduced). Increases system development speed Assists to identify any problems with the efficacy of earlier design, requirements analysis and coding activities

Helps to refine the potential risks associated with the delivery of the system being developed Various aspects can be tested and quicker feedback can be gained from the user Helps to deliver the product in quality easily User interaction available during development cycle of prototype Reduces development time. Reduces development costs. Requires user involvement. Developers receive quantifiable user feedback. Facilitates system implementation since users know what to expect. Results in higher user satisfaction. Exposes developers to potential future system enhancements.

Disadvantages of prototyping
Producer might produce a system inadequate for overall organization needs User can get too involved whereas the program can not be to a high standard Structure of system can be damaged since many changes could be made Producer might get too attached to it (might cause legal involvement) [verification needed] Not suitable for large applications Over long periods, can cause loss in consumer interest and subsequent cancellation due to a lack of a market (for commercial products) May slow the development process, if there are large number of end users to satisfy. Can lead to insufficient analysis. Users expect the performance of the ultimate system to be the same as the prototype. Developers can become too attached to their prototypes Can cause systems to be left unfinished and/or implemented before they are ready. Sometimes leads to incomplete documentation.

Rapid prototyping is a group of techniques used to quickly fabricate a scale model of a physical part or assembly using three-dimensional computer aided design (CAD) data. Construction of the part or assembly is usually done using 3D printing technology. The first techniques for rapid prototyping became available in the late 1980s and were used to produce models and prototype parts. Today, they are used for a much wider range of applications and are even used to manufacture production-quality parts in relatively small numbers.

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What is Rapid Prototyping? Rapid Prototyping is a manufacturing technology that quickly builds a prototype part. Many different technologies are available that are considered Rapid Prototyping, and many can also be used for production manufacturing. Although most Rapid Prototyping systems use a form of layered additive manufacturing, they can also use a variety of other methods such as high-speed machining, molding, casting, and extruding. Rapid Prototyping, often called RP, is rapid prototyping when the entire process of going from a computer design to a physical model is faster than more traditional manufacturing technologies. Wikipedia has a good article on the subject. What is Rapid Tooling and how is it Different from Rapid Prototyping? The only difference between Rapid Tooling and Rapid Manufacturing is the end use of the parts produced with the process. Both use rapid prototyping technologies to quickly make a part. But for Rapid Tooling, the part is used in another manufacturing process as a tool. What is 3D Printing and how is it Different from Rapid Prototyping? 3D Printing refers to a subset of rapid prototyping that goes directly from a 3D computer model to a prototype with very little user interaction other than defining some preferences. The process is designed to be as easy as printing from a computer to paper. In many ways the name is a marketing label to clearly emphasize the affordability and ease of making prototypes using systems that are labeled as 3D Printers. It is also meant to appeal to a larger, less engineering and manufacturing oriented audience. What are some of the other names for Rapid Prototyping? 3D Printing, layered manufacturing, additive manufacturing, direct digital manufacturing, digital prototyping, digital fabricator, desktop fabricator, desktop manufacturing, desktop prototyping. People often use the names of various prototyping techniques to refer to rapid prototyping, and even more often the acronyms for those technologies. Examples are Stereolithography or SLA and Fused Deposition Modeling or FDM. What is Layered Manufacturing and why do most Rapid Prototyping Technologies Use it? Layered Manufacturing builds parts up, one thin layer at a time. Most traditional manufacturing methods start with a block and remove material, or shapes material using a tool of some kind. Layered manufacturing is often called Additive Manufacturing because it adds material rather than taking it away or molding it. The best way to visualize layered manufacturing is to think of taking a real part and chopping it into very thin layers. Then stack those layers back up one on top of the other. Layered manufacturing does the chopping in a computer program, and tells a machine how to create each layer. When and how is Rapid Prototyping used in Product Development? Rapid prototyping can be used at almost every step in your product development process. At any point where you need a physical part you can benefit from Rapid Prototyping. Examples are: Conceptualization: Initial Design:

concept models, marketing mockups form, fit, and function testing, visualization

Detail Design: Production:

testing, test fixtures, assembly testing, fit, form and function testing. tooling, mockups for process planning

What are the different types of Rapid Prototyping Technologies and their Advantages and Disadvantages? Unfortunately there is no one technology that is perfect at everything. The following table is a basic listing of the main advantages and disadvantages.

TECHNOLOGY SLA (Stereolithography ) SLS

ADVANTAGE Smooth Accurate Detail

DISADVANTAGE Temperature Sensitive, Brittle, Brittles over Time

BEST USE Marketing Models Fit Checks

Durable, Speed on Large Projects Cost Effective Durable True Plastics

Rough Surface, Erratic Accuracy Lower Resolution Weak Layer-to-layer

Functional Models

FDM (Fused Deposition Modeling) POLYJET

Engineering Models Internal Reviews

Adjustable Material Properties Weak Material Properties Speed Fine Layers Cost Accurate True Materials Long Lead Time Cost

Elastomeric Models Overmold Models Metal Models Precision Work

CNC MACHINING

What is a STL (STereoLithography) File? The STL file is a file format developed in the early days of Rapid Prototyping by 3D Systems as a simple and portable format that could be used across CAD systems to define the solid geometry to be made in a Rapid Prototyping machine. It is a triangular facet representation, the surfaces of the solid are modeled as a collection of triangles that share vertices and edges with neighboring triangles. Most CAD tools can output an STL file.STL is also known as

Standard Tessellation Language STL files describe only the surface geometry of a three dimensional object without any representation of color, texture or other common CAD model attributes

What is the most commonly used Rapid Prototyping Technology? For many years the most commonly used technology is Fused Deposition Modeling. Originally only available from Stratasys, many other providers have adopted the technology. The best way to see how the various technologies stack up is through the Wohlers Report, an annual summary of the industry.