Rapid Prototyping - Definition, Method - Essay Example

?RAPID PROTOTYPING INTRODUCTION: In present era no new products remain ‘newer’ for a long time. Reducing the overall product development life time (eventually the cost) is the need of the time in current industrial era. The manufacturers are curiously working on reducing the time of the product development life cycle (Smith 1990). Nowadays product completion in the market is a lot tougher than it was in the earlier decades of the 21st century. An average product life cycle ranges from a year to a couple of years depending on the product. These days only those manufacturers and organizations are considered successful that can analyze the needs of their consumer’s and client’s and rapidly modify their products accordingly. Rapid prototyping enables them to do just that by reducing the time needed to design and implement a product. In some cases RP techniques can reduce the prototyping time by 2X to 10X when compared to the older methods used for this purpose (Smith 1999). Companies ready to cope up with the customer demands and take lead to market their product prior than their competitors are inclined to survive in this competitive age. Therefore there are several companies who reduced their product development life cycle quite significantly as shown in following fig 1 (Smith 1990). History of rapid prototyping: Since the beginning of the industrial age prototypes have been considered a vital part of the designing of tools as well as structures. A prototype enables the manufacturer to test the functionality, out put, performance and optimality of the various design features that can be introduced into the actual product without risking additional manufacturing costs that may occur in case of an untested product. The concept of rapid prototyping originated in the late sixties, when Herbert Voelcker who was an engineering professor, decided to explore the possibilities of a computer controlled automatic tool that could design and manufacture a prototype using new and innovative methods. During the seventies, he proposed theories related to solid modeling, these theories then went on to become the basis of the algorithms and methods that are used for rapid prototyping today. In 1987 Carl Deckard who was a researcher in the University of Texas, developed a technique called selective laser sintering. Voelcker and Deckard made revolutionary developments as well as others after them, however Charles Hull is considered to be the father of rapid prototyping as he holds the patent for the instruments used in the development of 3D objects from 2D diagrams using Stereolithography. Nowadays a prototype can be produced fairly easily and efficiently as compared to the time when rapid prototyping hadn’t replaced subtractive manufacturing. Where has RP come from and where is it going: Rapid prototyping has been a valuable tool in the designer’s perspective for over a decade now, and the techniques involved have come a long way from since the time they were introduced. The main impact of this technology is in the replacement of traditional techniques in the final stages of product development. However,the greatest prospective for 3D modeling lies prior to the prototyping stage i.e. in the design process where better designs are envisioned. Over the last 20 to 25 years, products in the market have seen a tremendous increase in geometrical complexity. A typical example can be the automotive industry in which products have evolved from straight forward cars to custom built and even custom designed cars that some times look like some thing out of a science fiction movie. Initially in the 1970s car designs took 4 weeks at an average, later in the 1980s this time increased to 16 weeks, however during the 1990s CAD/CAM and CNC technologies helped to shave down the time to 8 weeks and last but not the least RP techniques eventually enabled designers to complete the task in 3 weeks instead. Rapid prototyping has helped engineers and designers shorten the design cycle by enabling them to create in 2 hr a prototype that would have taken a week without it. Such savings in time can be inspiring on a fractional basis, but the weeks saved are trivial compared to the typical 12-month development cycle of a product. Critical discussion on RP: Rapid prototyping is a technique that has evolved greatly over the past three to four decades. This technique has revolutionized industrial development by enabling designers to produce prototypes in a very short time period as compared to the old methods, which in turn enables the manufacturers to launch a fully tested product in the market. Apart from achieving rapid production, RP can also be used to minimize labor costs as it reduces costs for manufacturing, inspection, machining and assembling. It allows the manufacturers to incorporate improved design features into the original design at relatively low costs in terms of material consumption as well as time, both of which are valuable resources for a company. Communication gaps between the clients and the designers have always been a problem for a manufacturer because in most cases, the clients failed to explain their true requirements or the designers were unable to comprehend the client’s needs which resulted in disappointment for the clients. RP can play a vital role in bridging such gaps as the marketing, engineering, management and manufacturing staff can be put on an even footing in the design evaluation process. Those involved in the development cycle can actually touch, see and handle the prototype just like the eventual customers. Involving the end users in the development cycle is also a good idea; it can simply be done by creating several prototypes and offering them to some of the likely customers. The best features can then be highlighted on the basis of customer feedback about the prototypes and then a final product can be launched that incorporates all of those features. Apart from its advantages, rushing into production via RP, some design features may be overlooked thus resulting in endless rectification and revision. Sometimes limited capabilities of the prototyping tool may limit the design features of the required prototype as well. No matter how unlikely it seems the fact cannot be ignored that the prototyping machine may fail to implement the prototype design accurately which may result in tedious corrections or even redesigning the object. Prototyping Methods other than RP: Rapid tooling (RT) creates an initial part and then from that part creates a mold through which additional parts can be made. Another prototyping method ia the traditional injection molding, which is primarily used for production, however it can also be used for prototyping. Rapid injection modeling (RIM), mills aluminum molds using CNC machines in which true injection parts can be made, while using the 3D CAD model as a reference. Prototypes play several roles in the product development life cycle Chua (2003) as following: Learning and experimenting Testing and proofing Synthesis and interactions Communication and interactions Scheduling and markers APPLIED INDUSTRY Rapid prototyping is widely used in the automotive, aerospace, medical, and consumer products industries. Aerospace industry In aerospace industries, rapid prototype method is used for the production of complex parts. Boeing’s Rocketdyne has used the RP technology to produce hundreds of parts of space shuttle and international space station. Rapid prototyping is also used for the production of parts of fighter jets as well as other military vehicles. Medical Applications RPT has created a new market in the world of orthodontics. Stereolithography can be used to produce custom fit, clear plastic aligners in a customized mass process. The RP technique is also used to make hearing instruments. The instrument shells produced are stronger, fit better and are biocompatible to a very high degree. The ear impression is scanned and then digitized with the help of an extremely accurate 3-D scanner. Then the digital image is converted into a virtual hearing instrument shell by the help of a 3D CAD software .Thanks to the accuracy of the Rapid Prototyping process, instrument shells are produced with high precision and reproducibility. In the case of repairs, an absolutely identical shell can be manufactured quickly, since the digital data is stored in the system. Arts and Archeology Selective Laser Sintering with marble powders can be used to restore or duplicate ancient statues and ornaments, which suffer from environmental influences. The originals are scanned to generate the 3D data, damages can be repaired within the software and the duplicates can be created easily. One application is duplicating a statue, it can be done by simply digitizing the original statue and then a smaller model can be produced to serve as a brass for bronze casting. References Smith , G. (June 1990) Fast-Cycle Product Development. Engineering Management Journal Vol. 2 No. 2. Smith, G. (1999)Leverage the Cycle-Time Capability of Your Rapid Prototypes. Time-Compression Technologies (European Edition). Vol 3. no 7, pp 50-57. Smith, G. (April 2001) Using Conceptual Modelers for Business Advantage. Time-Comparison Technologies pp 18-24. Chua C. K. Chua. S. (Aug 2003) Rapid Prototyping Technologies and Limitations. Computer Aided and Integrated Manufacturing Systems. A 5 Vol 3 : Optimization Methods, pp 165-185) Chua C. K., Leong F, Lim (March 2003) Rapid Prototyping Principles and Applications 2nd Edition. Read More