Question

Which of the following are problems with the current rapid prototyping technologies? a. Inability of the designer to design the part, Part shrinkage, & Inability to convert a solid part into layers b. Part accuracy, Inability to convert a solid part into layers, & Versatile materials available c. Poor machinability of the starting material, Part shrinkage, & Part accuracy d. Limited material variety, Mechanical performance of fabricated parts, & Part accuracy Short answer or a few-sentence short essay.

Answer 1

Nowadays, rapid prototyping technology still faces many problems, most of which come from the level of development of the technology itself, especially in the following aspects.
1. Process Problem
The basis of rapid prototyping is the principle of layered superposition. However, what materials to layered superpose and how to layered superpose are need to research. Thus, people are try to study and develop new layered superposed molding method, in order to further improve the performance of the article and the forming precision and efficiency.
2. Materials Problem
Prototyping materials research has always been a hot issue. The properties of rapid prototyping material should meet:
1) Conducive to rapidly and accurately process the mold;
2) Must be close to the final usage of the part on the strength, stiffness, moisture resistance, thermal stability and other requirements.
3) Good for subsequent processing of the rapid molding.
Development of new RP materials, especially composite materials, such as nano materials, heterogeneous materials and materials of other methods difficult to make is still our direction of effort.
3. Accuracy problem
At present, rapid prototyping parts are generally in a horizontal accuracy of ± 0.1 mm, as well as the height (Z) direction accuracy. The basic principle of rapid prototyping technology determines that the process is hard to achieve the surface quality and accuracy specifications of those manufactured with conventional machining. Thus, it is an important way of improving rapid prototyping precision that integrated the basic theory rapid of prototyping and the conventional machining method, which makes them complemented each other.
4. Software Problem
At present, the hierarchical slicing algorithm used in rapid prototyping system is based on the STL file format conversion, which is to use a series of triangular mesh to approximate the CAD model data files. This data representation method has many defects, such as the loss of data caused by some gaps in the triangular mesh, the layered effect caused by plane delamination which reduces the surface quality and forming precision of parts. So now, we should focus on the development of new model slicing methods, like feature-based model direct slice method or the surface layer method, thereby reducing the error caused by the triangular approximation and improving the forming accuracy and speed.
5. Application Area Problem
At present, the application field of rapid prototyping technology mainly lies in the new products development. The main purpose is to shorten the development cycle and get the effect of market feedback as soon as possible.