Catia customization for Design and Modeling of Two stage spur Gearbox

ABSTRACT


Introduction
Current scenario of the market is competitive.To sustain in the market for company product time to the market have to be minimum.Companies existing product demands from the customer are to be provided quickly as soon as possible.Existing product requirement has same parametric features of components for different specification.Design and modeling time of the product is generally 60-70% of overall time of the product development.Design phase has lot of potential where time can be saved.Parametric modeling can be used for saving the modeling time.Knowledge based approach can be useful for saving the design time.Lot of repetitive calculations can be saving for avoiding tedious work.CATIA software is selected having strong parameterization.Mechanical product selected is gearbox.Nowadays best of the best innovations are coming into picture, in these, researchers have made one way to reduce maximum design time by doing design automation concept which means integration of GUI developed with the help of computer programming language and market available CAD packages.Graphical User Interface (GUI) is the only way for users to communicate with the system.But no specific software is available for the design of a specific product.So by this dissertation approach it is very important to make one tailor-made software which will be useful for complete design of a specific component and output of the software should easily be integrated with other modeling software.In this with use of Macro which means program written for specific task.For developing advanced macros for special needs Catia V5 is an open system.Macros may be useful for creating, analyzing, measuring, modifying.Translating, optimizing surfaces, solids, wireframes and more.Macros are useful for part operation, assembly operation and all multidisciplinary applications.

Literature Review
Many research attempts have been made in the area of parametric modeling.
Ruchik D. Trivedi et al [1] discussed about integrating the commercially available package Pro/E with Microsoft Excel spreadsheet for 3D parametric modeling.Various product variants of the inner ring of spherical roller bearing have been executed by parametric designing concept in Pro/Engineer Wildfire.
Umesh Bedse et al [2] discussed about developed GUI is made for the case study of design of CI engine parts like cylinder head, cylinder block, piston and crankshaft.CI engine is having many numbers of mechanical components, but parts named above are the most important parts of any CI engine.So design of these parts is useful to take into account to develop a GUI.And creo software is used for modeling.
Indrajitsinh J. Jadeja et al [3] discussed about the work reviews the procedural steps involved in the design of couplings and the development of the software package using visual basic as a tool for the design.This system is carried out on the case study of flange coupling and standard design equation being carried out together with the use of programming software and use CREO as modeling software.
Dhaval b. shah et al [4] discussed about the 3D models for flange type coupling and related dimension database in Microsoft Excel have been prepared.This Excel sheet has been linked with Autodesk Inventor to transfer data and relate to respective features of the part.User can update the model just by modifying the sheet.This takes comparatively very less time to generate complex part models with respect to generating them individually.This automation can further be proceeded by exporting models to the analysis or CAM package.
L.Karikalan et al [5] discussed about the the main purpose of this assignment is to provide a gear box with Low reduction ratio, low weight and efficient for engine up to 500cc.It should also be used in "All Terrain" vehicles.

CATIA V5
CATIA (Computer Aided Three Dimensional Interactive Application) is a multi-platform CAD/CAM/CAE commercial software suite developed by French company Dassault Systems and it is marketed world-wide by IBM.Catia is the world's leading CAD/CAM/CAE software.For developing advanced macros for special needs Catia V5 is open system.A macro is a series of functions, written in a scripting language, that you group in a single command to perform the requested task automatically.These macros may be useful for creating, analyzing, measuring, modifying.Translating, optimizing surfaces, solids, wireframes and more.Macros are used to save time, reduce the possibility of human error by automating repetitive processes, standardization, improving efficiency, expanding Catia's capabilities, and for streamlining tasks.For creating basic structure and basic flow of program we require inputs, outputs, and supporting data from the user.Catia provides customization capability.In Catia the part Objects, which are used for developing part model i.e. three dimensional object are structured under a automation tree.

CATIA V5 MACROS
A macro is a series of functions, written in a scripting language, that you group in a single command to perform the requested task automatically.In simple it is a piece of code written in certain programming language which groups a set of operation that defines a certain task.For each task separate code is written and assembled together by using forms.

CATIA Customization/Automation Objects
In CATIA the part objects, which are used for developing part model i.

Result and Discussion
Design calculations

Conclusion
The objective was to customize CATIAV5 for design two stage spur gearbox with minimum user requirements (inputs).With the help of this customization gearbox is generated.Also the time required for generating part model (three dimensional model) of gearbox is reduced to few minutes.This part model can be used to draft different views of the gearbox which can directly be used for manufacturing processes.Thus, customization will increase productivity of the designer with increase in quality of design which in turn reduces lead time for design of gearbox.
e. three dimensional object are structured under a tree as shown in the following figure.As and when needed the part object can be extracted with the macro programming for customization or automation of CATIA V5 The Part Document object aggregates, or includes, the part tree structure starting with the Part object located at the top of the part specification tree.These Part Document objects are: Origin Element, Geometric Elements, Bodies and Part objects are: Constraints, Relations, Parameters, and Factory3D, Shape Factory (Sketches, Geometric Elements, and Shapes).

Figure 1 .
Figure 1.Part Modeling Object Tree

Figure 2 . 1 .
Figure 2. Methodology1.First user need to give input parameters of gearbox to GUI form The input parameters are as follows

Figure 5 .
Figure 5. Drafted View of Gearbox