Applications of Design for Manufacture and Assembly

Sunithkumar H G Mtech (CIM)

Technical Seminaron

2

CONTENTS Slide No• INTRODUCTION 3-5

• LITERATURE SURVEY 6-8

• METHODOLOGY 9-17

• RESULTS AND DISCUSSION 18

• CONCLUSION 19

• REFERENCES 20

3

INTRODUCTION• Twenty percent of the world’s population, or 1.4 billion people, live

on less than $1.25 a day.[1]• Engineers have the skills to design products that can help solve the

challenges faced by poor individuals. Products designed for this group will generally be more effective as engineers consider the principles of Design for Manufacture and Assembly (DFMA).

• The DFMA principles can help lower costs, but the principles used in the developed world do not always apply in the developing world.

• Design for manufacturing and assembly is usually used in the early product design stage for both system and detailed design levels in determining the components, subassemblies, fasteners. etc.[2]

4

• Redford and Chal state that any DFA method should have the following features [3]

It should be a complete method as regards to procedures for evaluating assemblability and should be creative enough to obtain procedures for improving assemblability.

It should be a systematic step-by-step procedure, which considers all relevant issues.

It should be able to measure assemblability objectively, accurately, and completely.

It should be user friendly and should have good quality.• DFA methods employing knowledge-based approaches

5

• The researcher Boothroyd and Dewhurst have developed a successful method to help designers to redesign their products, to cut costs, improve performance and reduce assembly time. It is called Design for Assembly. [4]

• The methodology DFMA has had great success in a good number of leadings design companies around the world.

6

LITERATURE REVIEW• Amy E. Wood et al [1] redesigned a pineapple juicer

using the modified DFMA principles. In comparing the two designs, he concluded that the second juicer had better performance, easier to use and clean, less expensive to produce, and was significantly easier to manufacture because the modified DFMA principles were considered.

7

• Pedro Perez V and Luis Torres T [4] The application of the Fuzzy-Evolutionary method to the well known Boothroyd-Dewhurst Design for assembly methodology is proposed. This hybrid methodology analyzes and optimizes manual assembly for different assembly situations and conditions, identifies sources of variability in process assembly time to new products.

• The experimental results show that is possible to conclude that the Fuzzy-Evolutionary Strategy method is a suitable methodology for predicting and optimizing the assembly time of new products.

• Wenlei Zhang et al [5] Assembly feasibility of aero engine is of vital importance. In this paper Design for Assembly system dedicating to aero engine is presented. Applications of this system have proved it operates efficiently, effectively, easily and smartly.

8

• Chris Fell. [6]The Successful development of a MEMS gyroscope, targeted at high volume, low cost applications. For this he uses Design for manufacture approach and applied it to silicon MEMS gyroscope. A second generation MEMS gyroscope has satisfied emerging market requirements for lower cost, high volume rate sensors.

• Bhavesh Mistry et al [7] It mainly concentrates on how to apply DFMA in development of a product or to improve the already existed design of the products. Here an attempt is made to use the concept of DFMA on dual plate check valve. This research explored the application of DFMA to improve the assembly.

• Based on several application of DFMA it can be seen that Part count, design and process are simplified.

9

Fig.1 Modified DFMA Principles for the developing world

METHODOLOGY

10

• Simplify the design and reduce the number of parts as necessary.

• Standardize and use parts and materials that are common in the context where the product is to be manufactured, along with supporting tools.

• Mistake-proof product design or include barriers to reverse engineering as necessary.

• Design for automated production when local manual production is cost prohibitive.

11

Fig.2 Pineapple juicer [1]

12Fig.3 A flow chart of selecting parts [3]

13

Table. 1 Information structure of stapler A & stapler B [3]

14

Table.2 Information structure of stapler C

15

Table.3 Information structure of a new stapler

16Fig 4.Boothroyd and Dewhurst DFMA procedure [8]

17Fig. 5 Influential factors in DFMA of weldments

18Fig. 6 Integrated DFMA–PDM procedure of for welded structures.

19

Results & Discussions• In comparing the two designs, the second juicer had better

performance, was easier to use and clean, was less expensive to produce, and was significantly easier to manufacture in because the modified DFMA principles were considered. One unanticipated problem that we encountered in their experiment in Brazil was a lack of quality control in the production of the 20 pineapple juicers. [1]

• The part count is reduced from 13 to 11 and total assembly time is reduced from 69.96 sec to 63.01 sec. [3]

20

Conclusion• Design for Manufacture and Assembly principles play an

important role in designing a product that can be manufactured in a developing world context. These principles do not always apply and are sometimes in conflict, especially in the developing world. With minor modification and clarification, the principles can be applied more robustly to design for customers that have different cultures, traditions, customer needs, and manufacturing capabilities.

21

References1. Amy E Wood, Charls D Wood and Christopher A. Mattson. ‘Application and Modification of

Design for Manufacture and Assembly Principles for the Developing World’, IEEE 2014 Global Humanitarian Technology Conference, July 2014.

2. Justin J.Y. Lin. ‘Research on Collaborative Concept Design Integrating the Application of Virtual Reality and DFMA’, IEEE, pp.727-732,2008.

3. XiuHua Ma and ManSig Kim. ‘A systematic Design for Assembly Method through the Combination of Subassemblies in Product Family’, International Conference on Smart Manufacturing Application, pp.261-266, April 9-11, 2008.

4. Pedro Pérez V., Luis Torres T. ‘Improving product design using a Fuzzy-Evolutionary approach to predict and optimize the assembly time of a new product’ , Proceedings of the Electronics, Robotics and Automotive Mechanics Conference (CERMA'06),IEEE,2006.

5. Wenlei Zhang, Cheng'en Wang and Jiapeng Yu. ‘A Design for Assembly System for Aero Engine’ International Conference on Computer and Automation Engineering, IEEE, pp.328-331 2009.

6. C.P. Fell. ‘Development of a second generation low cost MEMS gyroscope Design for anufacture’ The Institute of Engineering and Technology, pp.75-82.

7. Bhavesh Mistry, Dr. P. M. George and Saurin Sheth . ‘ Study and Scope of DFMA and GD&T in manufacturing process: A case study on Dual Plate Check Valve’, IEEE, 2008.

8. H. Tasalloti , H. Eskelinen, P. Kah, and J. Martikainen, ’ An integrated DFMA–PDM model for the design and analysis of challenging similar and dissimilar welds’ Materials and Design, pp.421-431,1 oct 2015.

Thank You