CHAPTER 1
INTRODUCTION
In the era of mechanization, every new dawn witnesses the launch of enterprising products and technologies. This has been made possible due to adoption of improved design and manufacturing processes by the manufacturing companies. Modern design and manufacturing processes are quite different from the traditional ones. The traditional ones were manual, involved lot of paperwork and traditional machine tools. Now the things have changed a lot with the introduction of computer systems, NC machine tools and the advent of information technology in design and manufacturing processes.
Although CAD and CAM have been significantly developed over the last three decades, they have traditionally been treated as separate activities. Many designers use CAD with little understanding of CAM. This, sometimes, results in design of non-machinable components or use of expensive tools and difficult operations to machine complex geometries. In many cases, design has to be modified several times, resulting in increased lead times and cost. Therefore, great savings in machining times and costs can be achieved if designers can solve machining problems of the products at the design stage. This can only be achieved through these fully integrated CAD/CAM systems [Lin and Tai, 1996].
Computer-aided design is the use of computer systems to help in creation, modification, analysis, or optimization of a design. CAD creates a technical drawing with the use of computer software and used to increase the productivity of the designer, improve the quality of design, improve communications through documentation, and to create a database for manufacturing. It used to design curves and figures in two-dimensional (2D) surfaces, and solids in three-dimensional (3D) with the help of CATIA, Pro-E or Solid Works software’s. In a traditional CAD setting, the computer primarily serves as a precise drafting and visualization tool, permitting the designer to view the emerging geometry from different angles and in different projections. A digital representation also makes it possible to carry out some analytical tasks such as determining volume or surface area of a part. [wikipedia.org]
CAM is the use of computer software to control machine tools and related machinery in the manufacturing of work pieces. CAM is a subsequent computer-aided process after computer-aided design as the model generated in CAD and verified can be input into CAM software, which then controls the machine tool. CAD and CAM work together in that the digital model generated in CAD is inputted to the CAM software package for manufacturing the part created in CAM software. [wikipedia.org]
1.2 Design - Manufacturing Integration
In compliance with the need of design manufacturing integration, this section explains the idea in detail and gives insight into the integration process. Design-manufacturing integration involves the generation of manufacturing information and data from the design data of a product.
Attempts for integration of CAD/CAM have been made by many researchers [Madan et al., 2007]. There are some systems available that are capable of generating manufacturing data from the CAD model. But human intervention is required at some steps. The main focus of present CAD/CAM integration is to generate the manufacturing data i.e. NC codes for NC and CNC machines. Besides the generation of CAM data base, we can also integrate the other functions such as process planning, factory management and robotic control.