Rapid Prototyping Techniques
Table of Contents
In the current globalization era, product development is the driving force for advancement in the world market. With the need to fabricate objects, researchers and developers entered the world of prototyping to facilitate progress in terms of widespread coverage as well as flexible performance. In 1982, rapid prototyping techniques were employed to fabricate scale models, which utilized three-dimensional computer aided design data (Gibson, Rosen, & Stucker, 2014). Currently, construction engineers have embraced this technology, and rapid prototyping is proved to decrease development time by allowing to make corrections of the product at the initial phase of the process thus giving a chance for early modifications. Therefore, in the light of reduction in the development time, rapid prototyping decreases the amount of expensive mistakes because introducing changes at the beginning is not so costly. Furthermore, design engineers engaged in rapid prototyping achieve extension of a product’s performance period by addition of the features that successfully minimize engineering changes and are necessary while removing redundant elements at the initial design stages. To facilitate rapid prototyping, design engineers utilize diverse techniques in order to increase the variety of many products. Therefore, in a concurrent engineering environment, rapid prototyping accelerates the production process and generally adds value to goods. While a number of such techniques allow manufacturers to realize many designs and save time and costs, most of these methods negatively affect the laboratory workers’ health and the environment.
In the event of product fabrication, engineers have several techniques at their disposal that can be utilized. For instance, one of them is stereolithography, which is based on selective polymerization of photosensitive resin with the use of ultraviolet rays. In other words, the method involves exposure of photosensitive resin to the ultraviolet beam, which is strategically positioned and moved horizontally to polymerize the resin within the cross section boundary (Page, 2012). As a result, wired polymer layer is lowered by a platform attached to it hence fresh layer of liquid resin covers cured ones. With this technique, engineers achieve accuracy in product fabrication in addition to a good surface finish. Comparatively, the prototypes are thin walled and of high quality making it a preferred method in industries (Chua, Leong & Lim, 2010). However, with the limited amount of materials, such as photopolymers, support structures are always needed in the process making it expensive and complicated because these structures can cause some difficulties at times. Furthermore, this technique exposes laboratory workers to numerous health risks. For instance, the use of flammble isopropanol to remove uncured coating of a finished product poses the danger of explosion (Gibson, Rosen & Stucker, 2014). In this regards, a small mistake can cause detonation hence endangering employees and surrounding environment. Similarly, explosion may occur because the raw materials, which are frequently used, are highly inflammable. Moreover, exposure to ultraviolet rays is insecure to humans because the beams damage eyes by causing cataracts, loss of color vision and eventually total blindness. To prevent health and environmental hazards, people involved in this process ought to wear protective glasses to shield their eyes from the harmful ultraviolet light.
Fused Deposition Modelling
Secondly, another technique that engineers may use in rapid prototyping is the fused deposition modelling (FDM). Generally, this model relies on melting coupled polymers with selective deposition of thin filaments of thermoplastics in a cross-hatching way. Wires, which are supplied in sealed pools, are threaded though FDM head, which moves horizontally, as the supporting table changes position vertically after completion of each layer (Gebhardt, 2012). The positive side of this technique is that it uses a variety of materials thus it is unlimited to choice. Similarly, machines are less expensive making the whole process economical. Since post curing is not required, design engineers do not incur more expenses as it is needed in cases of post refinement. As a result, fused deposition modelling is relatively cheap and consumes less time. Significantly, the materials used are environment-friendly, thus, workers are exposed to less health hazards. On the other hand, the FDM technique is not applied to small features as well as thin walls because it takes much time when working on dense parts as its Z-axis is weak. Consequently, support systems are required for some materials what will result in tedious work. Moreover, the needed sustenance increases expenses making the whole process costly.
Selective Laser Sintering
Thirdly, selective laser sintering is another technique used in rapid prototyping. Laser beams are applied selectively to melt fused powdered material spread on the layer, and the powder is metered in required amounts by the use of rotating roller placed on the table (Pham & Dimov, 2012). The lesser ray fuses the powder within section boundaries through the hatching motion. Afterwards, the table is lowered through the distance to correspond to the powder layer on the initially constructed one. Unfiltered powder, therefore, acts as a support to the hanging portions. Significantly, applying this technique results in porous prototypes, hence impaired strength in addition to the surface finish. More notable is the fact that post curing is not required as well as limited use of support structures, thus the technnique is relatively less expensive (Pham & Dimov, 2012). Similarly, engineers have the variety of materials at their disposal to choose from what makes the process easy. Despite these advantages, using selective laser sintering has its own negative sides. For instance, the process is accompanied with numerous complexities in operation. Likewise, there are some difficulties in the material changeover unlike other techniques. With prototypes having rough surfaces, there is the need for post processing which results in extra expenditure. In relation to health and environmental risks, the selective laser sintering technique poses serious implications to human life. Notably, materials used in powder base systems put the environment in danger of the dust explosion. Furthermore, since ultraviolet rays are utilized, laboratory workers face the risk of eye damage and blindness. Apart from the loss of sight, exposure to chemicals leads to lung damages, skin diseases and other allergies.
In essence, in the current global economy coupled with massive scientific and technological innovations, product fabrication is simply inevitable. Used in a wide range of application, rapid prototype technologies are in position to change objects despite their complexity by utilization of addictive processes. To achieve success in prototyping designs, engineers, therefore, need to evaluate all techniques available and eventually use the best one. However, preventive measures should be taken in the event of engaging in rapid prototyping since the varieties of raw materials utilized in the process are the potential health hazard to both humans and the environment. Generally, the usage of chemicals in different techniques results in health problems if they come into direct contact with individuals. Thus, this explains the reason why the majority of people working in rapid prototyping laboratories often suffer from lung diseases and numerous skin allergies as well as other health complications. If one does not take preventative actions, these exposures can be fatal because such health complications may cause serious illnesses like lung and skin cancer. Putting these challenges in mind, thorough studies ought to be conducted prior to rapid prototyping in order to reduce chances of risk occurrence like searching for current occupational safety and healthcare administration (OSHA) regulations. For instance, it is important to review possible hazards by investigating the instrument manually. Moreover, employees should wear protective garments when working in laboratories to avoid the direct contact with chemicals. Like other innovations, rapid prototyping has both positive and negative implications but by utilizing benefits while working towards reducing negative effect, the new methods will prove themselves to be useful in the current economy.