Abstract A lathe attachment has been developed for an existing CNC machine (installed with rapid prototyping attachment) using conceptual design. The CNC machine operates on mechatronic controls and a computer interface called CAMSOFT, and is used as a CNC Lathe after installing the respective attachment to it. The conceptual design phase, starts from an idea and different components of the lathe are designed as attachment using CAD mod- elling and is followed by fabrication phase. The lathe attachment is successfully developed and is installed to the CNC machine. The working of the CNC Lathe attachment is checked by making some machining operation like turning and thread cutting. The machining operations are successfully done. The CNC machine becomes multi- functional with the presently developed lathe attachment and the existing RP (rapid prototyping) attachment, and can be used accordingly by installing the respective attachment to it. The CNC machine is useful for  carrying research work in both the fields, when installed with the appropriate attachment.67746

Keywords    Conceptual design · CAD & modelling   ·CNC · Machining

Introduction

The concept of a new product includes product require- ments, functions, possible behaviors, form/structure (lay- out), and associated properties. Properties include material,

V. Roy (&) · S.  Kumar

Department of Mechanical Engineering, Indian Institute of Technology (BHU), Varanasi 221005,  India

e-mail: vivekroy.iit@gmail。com

assembly-level tolerance, critical surface roughness and hardness parameters, and critical  dimension.

Conceptual design and development process accelerates the process of product design and development. It is sup- ported by creativity, which leads to the generation of new and valued/innovative ideas. It is a very crucial aspect in the early stage of product development. It determines the function, form and the basic structure of the   product.

The process of conceptual design consists of (i) Fact gathering: The designer must have a good idea of what the customer wants in order to begin designing. The more information a designer can gather, the more easily he will be able to satisfy the customer with a pleasing design. (ii) Processing: Once the designer gathers the facts and looks over examples of similar products, creative side is kick in. This phase of the design process is characterized by note taking, sketching and  organizing  the  work.  (iii) Design: A misconception of the design process by customers not familiar with it is that designers start at design. Customers need to be educated on the first two steps. If the first two steps are done well, the design process is streamlined and the results are more accurate. The design phase of the process may be repeated several times. (iv) Refinement: Once the designer receives input from the customer, the refining process takes place. One design is decided upon, and the designer brings it up to industry standards so that the design can be printed, manufactured or implemented depending   on   the   type   of   design   being    developed.

(v) Implementation: The finished design is sent to the appropriate vendor.

Creativity has a great role in the process of conceptual design. The proper strategy and the design objectives must be very clear to guide the creative phase. CAD has a great role in this design process [1–3]; it helps in getting the various possible designs, when the problem definition is

188 J. Inst. Eng. India Ser. C (April–June 2013)   94(2):187–195

laid on the basis of the need. Each design is then evaluated and analyzed for optimization, and if required; the changes are made to the design. When the best design is achieved, it gets finalized. During the design procedure, certain factors like proper functioning, cost, feasibility in manufacturing, feasibility in assembly, use of standard components, wear and replacements of parts etc. must be kept in   mind.