IMPROVEMENT OF GENERAL DESIGN THEORY AND METHODOLOGY WITH ITS APPLICATION TO DESIGN OF A RETRACTOR FOR VENTRAL HERNIA REPAIR SURGERY
Date
2019-03-28
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
ORCID
Type
Thesis
Degree Level
Masters
Abstract
Open surgery is an efficient way to cure massive ventral hernias in the clinic. During the surgical process, a spatula is used to prevent intestine tissues from damage of suture passer, possibly causing damage and taking time to address the spatula. Therefore, a new prototype, which could address both issues, is under consideration. In order to design the new prototype that satisfies clinical use, this study was based on the retractor design by Dr. Luo (Luo’s retractor for short), which nevertheless had many shortcomings. An observation was made to these shortcomings that they are partially due to the ad-hoc design process taken to result in Luo’s retractor). This drove the research of this thesis into a close examination of the general design theory and methodology (DTM) in literature, aiming at improvements of DTM so that it is possible to apply the DTM to improve Luo’s retractor.
In this thesis, the general design theory and methodology, such as Axiomatic Design Theory (ADT) and Systematic Design Procedure (SDP), was examined closely. Several problems with them, e.g., missing a guideline to identify the so-called general function in SDP, missing a guideline to handle constraints in ADT, lack of a more formal model to capture design requirements, etc., were identified and studied. Specifically, a novel model to represent a design more formally was proposed, and a new general design process model was developed. The design of the retractor was then carried out by following the proposed general design process model with the improved DTM, which resulted in an improved retractor. The prototype of the new retractor was tested clinically with the help of surgeon (Dr. Luo) as well as simulated with the help of the finite element software.
Several conclusions can be drawn from this study and they are: (1) the new retractor is a viable device and is promising for further commercialization; (2) the general design theory and methodology is now more rational, formal and robust, ready for applications and for further development towards automating the general design process.
This thesis has made the following contributions to the field of medical device and to the field of general design theory and methodology. In the first field, a new medical device, i.e., retractor, is created and it will improve the ventral hernia repair surgery in terms of efficiency (time reduction by 37.5%). In the second field, this thesis provided a revised design theory and methodology that combines ADT and SDP, which may be called ADT-SDP, and has provided guidelines of how the ADT-SDP can be used for practical design problems.
Description
Keywords
Ventral hernia surgery, ADT-SDP
Citation
Degree
Master of Science (M.Sc.)
Department
Biomedical Engineering
Program
Biomedical Engineering