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rapid prototyping ppt.pptx
- 1. Rapid Prototyping MADE BY:- PATEL PRINSKUMAR ASHOKBHAI 216310319004 HET PARESHKUMAR PATEL 216310319006 PATEL HARSH ARVINDBHAI 216310319060 PATEL KRUTIK HARESHKUMAR 226318319007
- 2. Inroduction In manyfields, there is great uncertainty as to whether a new design will actually do what is desired. New designs often have unexpected problems. A prototype is often used as part of the product design process to allow engineers and designers the ability to explore design alternatives, test theories and confirm performance prior to starting production of a new product. Engineers use their experience to tailor the prototype according to the specific unknowns still present in the intended design.
- 3. defination Rapid Prototypingtechnology employs various engineering e.g. computer control and software techniques including laser, optical scanning, photosensitive polymers, material extrusion and deposition, powder metallurgy etc. to directly produce a physical model layer by layer (Layer Manufacturing) in accordance with the geometrical data delivered from a 3D CAD model.
- 4. Working Principle ofRapid Prototyping
- 5. Rapid Prototypinguses a standard data interface, implemented as the STL file format, to translate from the CAD software to the 3D prototyping machine. The STL file approximates the shape of a part or assembly using triangular facets. Typically, Rapid Prototyping systems can produce 3D models within a few hours.
- 6. Why Rapid Prototyping Prototyping can improve the quality of requirements and specifications provided to developers. Reduced time and costs. Users are actively involved in the development. Quicker user feedback is available leading to better solutions. Errors can be detected much earlier. Missing functionality can be identified easily
- 7. Limitation of RapidPrototyping High precision RP machines are still expensive. ca RP systems are difficult to build parts with accuracy under +/-0.02mm and wall thickness under 0.5mm. The physical properties of the RP parts are normally inferior to those samples that made in proper materials and by the traditional tooling. The RP parts are not comparable to (CNC) prototype parts in the surface finishing, strength, elasticity, reflective index and other material physical properties
- 8. Workflow of RPProcess All RP techniques employ the basic five steps process:- Create a CAD model of the design. Convert the CAD model to STL format. Slice the STL file into thin cross-sectional layers. Construct the model one layer atop another. Clean and finish the model.
- 9. Workflow of RPprocess
- 10. CAD Model Creation First, the object to be built is modeled using a Computer-Aided Design (CAD) software package. Solid modelers, such as Pro/ENGINEER, tend to represent 3-D objects more accurately than wire-frame modelers such as AutoCAD, and will therefore yield better results. This process is identical for all of the RP build techniques.
- 11. Conversion to STLFormat To establish consistency, the STL format has been adopted as the standard of the rapid prototyping industry. The second step, therefore, is to convert the CAD file into STL format. This format represents a three-dimensional surface as an assembly of planar triangles STL files use planar elements, they cannot represent curved surfaces exactly. Increasing the number of triangles improves the approximation
- 12. Example of STLmodel This figure shows a typical example of STL model which is composed of triangles And each triangle is described by a Unit normal vector direction and three points representing the vertices of The triangle
- 13. Slice the STLfile In the third step, a pre-processing program prepares the STL file to be built. The pre-processing software slices the STL model into a number of layers from 0.01 mm to 0.7 mm thick, depending on the build technique. "The program may also generate an auxiliary structure to support the model during the build. Supports are useful for delicate features such as overhangs, internal cavities, and thin-walled sections.
- 15. Layer by Construction The fourth step is the actual construction of the part. RP machines build one layer at a time from polymers, paper, or powdered metal. Most machines are fairly autonomous, needing little human intervention.
- 16. Clean and Finish The final step is post-processing. This involves removing the prototype from the machine and detaching any supports. Some photosensitive materials need to be fully cured before uses Prototypes may also require minor cleaning and surface treatment. Sanding, sealing, and/or painting the model will improve its appearance and durability.
- 17. Types of RapidPrototyping Technologies SLA-Stereolithography SLS-Selective Laser Sintering LOM-Laminated Object Manufacturing FDM-Fused Deposition Modeling 3DP Three Dimensional Printing
- 18. Advantage of RP Reduced design & development time. Reduced overall product development cost. Elimination or reduction of risk. Allows functionality testing at a fraction of the cost. Improved and increased user involvement during design stages of NPD. Ability to evaluate human factors and ergonomics.
- 19. Disadvantage Lack ofaccuracy. Added initial costs. Some rapid prototyping processes are still expensive and not economical. Reduced material properties like surface finish and strength. Rapid prototyping required skilled labour Limited material range. Overlooking some key features because they cannot be prototyped affects the prototype testing. End-user confusion, customers mistaking it for the finished project/developer misunderstanding of user objectives.
- 20. Application of RP Visual prototypes Concept models Functional prototypes Pre-production prototypes Production tools prototypes Production moulds for prototypes