A Thesis Submitted to the College of Graduate Studies and Research in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in the Department of Mechanical Engineering University of Saskatchewan Saskatoon
By Mehdi Hashemian
© Copyright Mehdi Hashemian, Jun 2005. All rights reserved.
PERMISSION TO USE
In presenting this thesis inpartial fulfillment of the requirements for a Postgraduate degree from the University of Saskatchewan, I agree that the Libraries of this University may make it freely available for inspection. I further agree that permission for copying of this thesis in any manner, in whole or in part, for scholarly purposes may be granted by the professor or professors who supervised my thesis work or, in theirabsence, by the Head of the Department or the Dean of the College in which my thesis work was done. It is understood that any copying or publication or use of this thesis or parts thereof for financial gain shall not be allowed without my written permission. It is also understood that due recognition shall be given to me and to the University of Saskatchewan in any scholarly use which may be made ofany material in my thesis. Requests for permission to copy or to make other use of material in this thesis in whole or part should be addressed to:
Head of the Department of Mechanical Engineering University of Saskatchewan 57 Campus Drive Saskatoon, Saskatchewan, Canada, S7N 5A9
Manufacturing globalization and sustainable development compel production enterprises tocontinuously seek improvements in their products’ performance, customization, environmental friendliness, cost, and delivery time. The challenges of this competition cannot be completely addressed through improving production processes because some issues can only be solved through more innovative ‘design’. This thesis investigates a new design paradigm called Design for Adaptability or Adaptable Design(AD) to address some of these challenges. The purpose of AD is to extend the utility of designs and products. An adaptable ‘design’ allows manufacturers to quickly develop new and upgraded models or customized products through adapting existing designs with proven quality and costs. An adaptable ‘product’ can be utilized under varying service requirements thus prevents premature productreplacement. Design adaptability and product adaptability provide economical and environmental benefits for AD. To make a product adaptable, its adaptability must be built-in during the design stage. Methods of design for ‘predetermined’ adaptations are categorized as Specific AD; these methods design products for versatility, upgrading, variety, and customization. Several of these methods such asmodular/platform design and design for upgrading have been studied for mechanical design. In the absence of predetermined adaptations, AD aims to increase the general adaptability of products. General AD involves fundamental research in design theory and methodology in order to develop practical design methods
and guidelines. This thesis introduces several original concepts and proposes thesubordination of a system to a rational functional structure as an approach for increasing general adaptability. Such a system would consist of a hierarchical assembly of autonomous functional modules, emulating the adaptable architecture of a ‘rational functional structure’. Methods and guidelines are proposed for making the design of mechanical systems closer to this ideal architecture. Accordingly,the thesis proposes a methodology for AD in which specific AD is performed first to take advantage of available ‘forecast’ information, and then general AD is performed in order to increase adaptability to ‘unforeseen’ changes. Also, a measure has been defined for the assessment of adaptability. The application of this methodology has been demonstrated through several conceptual design examples....