Reverse Engineering (Recovery Of A The Design Artifacts As A Case Study)

ABTRACT

Engineering practice tends to focus on the design and implementation of a product without considering its lifetime. The notion of computers automatically finding useful information is an exciting and promising aspect of just about any application intended to be of practical use [11]. This work introduces readers to the term reverse engineering (RE), and to the associated techniques that can be used for scanning physical parts.

In addition, the chapter presents the process of reverse engineering and the strategy for scanning and converting the scanned data into a 3-D surface or solid model.

CHAPTER ONE

1.0                                                        INTRODUCTION

Engineering is the profession involved in designing, manufacturing, constructing, and maintaining of products, systems, and structures. At a higher level, there are two types of engineering: forward engineering and reverse engineering.

Reverse Engineering: In some situations, there may be a physical part without any technical details, such as drawings, bills of material, or without engineering data, such as thermal and electrical properties.

The process of duplicating an existing component, subassembly, or product, without the aid of drawings, documentation, or computer model is known as reverse engineering.

Reverse engineering is the reverse process of the design activity. It basically consists on the reconstruction of design models associated to a real product. The main goal of the reverse engineering is to go back to the results of the original design process in order to create a copy of the product,

Reverse engineering has been developed as an alternative solution to define or redefine objects. Nowadays, it is widely spread in the manufacturing industry. It is used for the capitalization of information and knowledge, which haven’t been collected yet. This is a critical issue for the development and evolution of products. We can list some of its applications in industry: long life products maintenance (trains, boats, aircrafts, nuclear power plants, etc.), redesign of existing products in order to improve them, competitor’s product’s analysis.

The work is focused on design artifacts. Different design artifacts become inconsistent with the current implementations, making maintenance tasks difficult and error prone. Software maintenance of large systems depends on several factors including the existence of accurate documentation of the system design. In some cases, software and documentation fail to be consistent in that the documentation, and subsequently the design, is rarely updated to reflect modifications made to the system. In other cases the original system design does not have any type of existing documentation and, as such, any rationale behind the design decisions made during the implementation of the system are lost. In either case, lack of a consistent design has many impacts on the effectiveness of any efforts to maintain and modify existing systems. Reverse engineering is a crucial part of software maintenance and a maintainer needs to understand the code before attempting any modification. Reverse engineering is the process of creating higher-level of abstraction from source code and available documentation [2]. Reverse engineering can be used for a variety of purposes: to reconstruct or improve documentation; to facilitate software maintenance or conversion activities; or to redesign and re-engineer an existing system.

Unfortunately, source code does not contain much of the design information and additional information sources are required. Usually the scale of the software is often large, the maintainer also needs some automated support for the understanding and the recovery of the design artifacts. The design information from a combination of code, existing design documentation (if available), and general knowledge about problem and application domain is required to recover the design artifacts.

This work first briefly summarizes the reverse engineering abstraction levels and important concepts necessary to understand the process. After that, it describe a methodology in which human and computer interact to recover the design artifacts, which is followed by a review of the experience in using this process for the case study.

1.1                                           BACKGROUND OF THE STUDY

In today’s intensely competitive global market product enterprises are constantly seeking new ways to shorten lead times for new product developments that meet all customer expectations. In general, product enterprise has invested in CADCAM, rapid prototyping, and a range of new technologies that provide business benefits. Reverse engineering (RE) is now considered one of the technologies that provide business benefits in shortening the product development cycle.

Reverse engineering is the process by which a man-made object is deconstructed to reveal its designs, architecture, or to extract knowledge from the object; similar to scientific research, the only difference being that scientific research is about a natural phenomenon.[1]

Reverse engineering is also defined as the process of obtaining a geometric CAD model from 3-D points acquired by scanning/ digitizing existing parts/products. The process of digitally capturing the physical entities of a component, referred to as reverse engineering (RE), is often defined by researchers with respect to their specific task (Motavalli & Shamsaasef 1996). Abella et al. (1994) described RE as, “the basic concept of producing a part based on an original or physical model without the use of an engineering drawing”. Yau et al.(1993) define RE, as the “process of retrieving new geometry from  a manufactured part by digitizing and modifying an existing CAD model”.

Reverse engineering is now widely used in numerous applications, such as manufacturing, industrial design, and jewelry design and reproduction For example, when a new car is launched on the market, competing manufacturers may buy one and disassemble it to learn how it was built and how it works. In software engineering, good source code is often a variation of other good source code. In some situations, such as automotive styling, designers give shape to their ideas by using clay, plaster, wood, or foam rubber, but a CAD model is needed to manufacture the part. As products become more organic in shape, designing in CAD becomes more challenging and there is no guarantee that the CAD representation will replicate the sculpted model exactly.

Reverse engineering provides a solution to this problem because the physical model is the source of information for the CAD model. Another reason for reverse engineering is to compress product development cycle times. In the intensely competitive global market, manufacturers are constantly seeking new ways to shorten lead times to market a new product. Rapid product development (RPD) refers to recently developed technologies and techniques that assist manufacturers and designers in meeting the demands of shortened product development time.

1.2                                                  PROBLEM STATEMENT

In the last decade producers used to go for research, do some try-and-error before they produce a particular product, and this consumes time, energy and resources. But in today’s intensely competitive global market the story is no longer the same. Reverse engineering have overcome this problem, with reverse engineering, man-made object is deconstructed to reveal its designs, architecture, or to extract knowledge from the object; similar to scientific research. Reverse engineering is an analysis process intended to increase the overall comprehensibility of a system for both maintenance and new development.

1.3                                                   AIM OF THE PROJECT

The aim of this work is to discuss a means of rapid prototyping, and a range of new technologies that provide business benefits. This work is focused on to recover the design artifacts.

1.4                                         SIGNIFICANCE OF THE PROJECT

Reverse engineering (RE) is now considered one of the technologies that provide business benefits in shortening the product development cycle. it bring a means of producing products with ease which reduces time of production, research and resources.

1.5                                            APPLICATION OF THE STUDY

Reverse engineering is applicable in the fields of mechanical engineering, electronic engineering, software engineering, chemical engineering,[2] and systems biology.[3] manufacturing, industrial design, and jewelry design and reproduction.

1.6                                            ADVANTAGES OF THE STUDY

1. You can reproduce products and parts without needing the original design measurements and specifications.
2. It extends the life of your machinery and equipment, which in turn reduces operating costs.

• You save time and human resources because you don’t have to create a design entirely from scratch.

1. Reverse engineering can help you recreate outdated parts to keep your machines running longer. There’s no need to replace the whole machine when you can reproduce the malfunctioning part and have it manufactured for you instead. This same process makes resizing and minor adjustments to parts simpler as well.
2. You can easily make minor adjustments and product improvements.

1.7                                           LIMITATION OF THE PROJECT

1. You can face legal ramifications if you don’t follow copyright and patent laws.
2. Not every component or product is a great candidate for reverse engineering.

1.8                                                    PURPOSE OF STUDY

Following are reasons for which we should do reverse engineering of a product:

1. The original manufacturer of a product no longer produces a product
2. There is inadequate documentation of the original design
3. The original manufacturer no longer exists, but a customer needs the product
4. The original design documentation has been lost or never existed
5. Some bad features of a product need to be designed out. For example, excessive wear might indicate where a product should be improved
6. To strengthen the good features of a product based on long term usage of the product
7. To analyze the good and bad features of competitors’ product
8. To explore new avenues to improve product performance and features
9. To gain competitive benchmarking methods to understand competitor’s products and develop better products
10. The original CAD model is not sufficient to support modifications or current manufacturing methods
11. The original supplier is unable or unwilling to provide additional parts
12. The original equipment manufacturers are either unwilling or unable to supply replacement parts, or demand inflated costs for sole source parts
13. To update obsolete materials or antiquated manufacturing processes with more current, less expensive