Reverse Engineering

REVERSE ENGINEERING WITH CASE STUDY OF CARRIER COMPRESSORS

Sahil S DEOKAR ROLL NO 17 | DIV S

REVERSE ENGINEERING Introduction: Reverse engineering is taking apart an object to see how it works in order to duplicate or enhance the object. The practice, taken from older industries, is now frequently used on computer hardware and software. Software reverse engineering involves reversing a program's machine code (the string of 0s and 1s that are sent to the logic processor) back into the source code that it was written in, using program language statements. Hardware reverse engineering involves taking apart a device to see how it works. For example, if a processor manufacturer wants to see how a competitor's processor works, they can purchase a competitor's processor, disassemble it, and then make a processor similar to it. However, this process is illegal in many countries. In general, hardware reverse engineering requires a great deal of expertise and is quite expensive. Another type of reverse engineering involves producing 3-D images of manufactured parts when a blueprint is not available in order to remanufacture the part. To reverse engineer a part, the part is measured by a coordinate measuring machine (CMM). As it is measured, a 3-D wire frame image is generated and displayed on a monitor. After the measuring is complete, the wire frame image is dimensioned. Any part can be reverse engineered using these methods. The term forward engineering is sometimes used in contrast to reverse engineering. Reverse engineering is the process of extracting knowledge or design information from anything manmade. The ultimate goals for obtaining such information are varied. A typical goal for reverse engineering a product is to create a (possibly improved) copy or even a knockoff; this is usually the goal of a competitor. However, another goal for reverse engineering may be defeating a product in some way; for example reversing suspected malware for the purpose of facilitating its identification and removal, e.g. by an anti-virus or, as another example, cracking software for the purpose of removing its protection. The process often involves disassembling something (a mechanical device, electronic component, computer program, or biological, chemical, or organic matter) and analysing its components and workings in detail. Reverse engineering has its origins in the analysis of hardware for commercial or military advantage. However, the reverse engineering process in itself is not concerned with creating a copy or changing the artifact in some way; it is only an analysis in order to deduce design features from products with little or no additional knowledge about the procedures involved in their original production. Theory: The easy availability of computer-aided design packages, reverse engineering technology has become a practical tool to create a three-dimensional virtual model of an existing physical part. That, in turn, has made the use of 3-D CAD, computer-aided manufacturing, or other computeraided engineering applications easier. The reverse-engineering process needs hardware and software that work together. The hardware is used to measure an object, and the software reconstructs it as a 3-D model. The physical object can be measured using 3-D scanning technologies like a coordinate measuring machine, laser scanner, structured light digitizer, or computed tomography.

Handheld scanners can now digitize 3-D surfaces in real time and input that information into CAD systems. The tools further speed the reverse engineering process.

Following are reasons for reverse engineering a part or 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 technologies Another reason for reverse engineering is to compress product development 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 reduced product development time. For example, injection-molding companies must drastically reduce the tool and die development times. By using reverse engineering, a three-

dimensional product or model can be quickly captured in digital form, re-modeled, and exported for rapid prototyping/tooling or rapid manufacturing. Reverse engineering is also used by businesses to bring existing physical geometry into digital product development environments, to make a digital 3D record of their own products, or to assess competitors' products. It is used to analyse, for instance, how a product works, what it does, and what components it consists of, estimate costs, and identify potential patent infringement.

Reverse engineering can be viewed as the process of analyzing a system to: 1. Identify the system's components and their interrelationships 2. Create representations of the system in another form or a higher level of abstraction 3. Create the physical representation of that system It can be said that reverse engineering begins with the product and works through the design process in the opposite direction to arrive at a product definition statement (PDS). In doing so, it uncovers as much information as possible about the design ideas that were used to produce a particular product.

Case Study: This is A Case Study in Reverse Engineering and Industrial Competitive Assessment of Carrier Scroll Compressor of Carrier Engineering Company. In 1902, Willis Carrier invented the air conditioner to control the heat and humidity for a printing process in Brooklyn, NY printing company. After designing similar systems for a series of manufacturers, Carrier raised $32,600 to form Carrier Engineering Company in 1915. In 1924, Carrier built the first “comfort cooling” system for J.L. Hudson Department Store in Detroit, MI. By 1930, comfort cooling systems were installed in 300 movie theaters nation wide. In 1928, Carrier developed the first residential air conditioning system, but the Great Depression and WW II put home air conditioning on hold for about 20 years. In 1955, William Levitt predicted that air conditioning would be a basic feature in all new homes. In 1985, 70% of all new homes had air conditioning. The majority of refrigeration and air conditioning systems in place today employ the simple vapor compression refrigeration cycle. These systems include a compressor, a condenser, an expansion valve and an evaporator. Like the engine of an automobile, the compressor is the heart of he refrigeration system. It is the most complicated and costly component and is responsible for over 90 % of the power consumption. In the 1980s, the old standard reciprocating (piston) compressors were being phased out by efficient, quiet, and reliable new compressors such as the rotary, scroll and screw compressor. Although these new compressors were required for the bulk of their residential products, Carrier somehow found themselves without the ability to manufacture these compressors…this is like a GM or Ford without the ability to manufacture engines. In the mid 1980s, Carrier embarked on a program to gain back their ability to manufacture their own compressors. In most typically sized room air conditioners the rotary compressor is used. They decided to design their own rotary compressor by reverse engineering. The plan was a complete success. Using the mid 80s fleet of rotary compressors as a guideline, a small group of Carrier engineers designed and developed a new rotary compressor. The Carrier rotary compressor was the most efficient compressor on the market.

In the late 1980s, given the success of the rotary compressor project, Carrier engineers embarked on a similar project to reverse engineer the scroll compressor. Scroll compressors were quickly gaining the market share in typical residential central air conditioning applications.

Hitachi

Mitsubishi

Copeland

Although the same approach was used in reverse engineering the scroll compressor... after 3 years, and untold $ spent, the Carrier scroll compressor was noisy, in-efficient and unreliable. What went wrong?  The scroll compressor is a much more complicated device than the rotary compressor.  Reverse engineering is more than just taking apart competitor’s products and re-designing based on appearance, materials and manufacturing processes.  To develop a viable new design using existing products as a guideline, engineers must understand why these products are designed the way they are.  In other words, as engineers, we need to know, not only the what and the how of the design, but also the why of the design.  One way to understand the why of design is through detailed testing of competitor’s product lines. To perform the required testing, Carrier contracted UTRC, the central research organization of their parent company, United Technologies Corporation. The project, which entailed acquiring, dissecting, evaluating, instrumenting, and testing competitor’s compressors, was called Competitive Assessment. In addition to competitor’s products, Carrier products were tested under the same controlled operating conditions. A Carrier Scroll Compressor was instrumented with 4 eddy current proximity probes, 11 pressure transducers, 6 heat flux gages, 37 thermocouples and an acoustic emission sensor. In 1993, Carrier entered an agreement with Bristol Compressor Co. to form a joint venture called Scroll Technologies in Arkadelphia, Arkansas. Scroll Tech manufactures hundreds of thousands of scroll compressors per year.

Scroll Tech Corporation

Copeland Corp. Compressor Sales Chart.

Conclusion:      1. 2. 3. 4.  1. 2.

Reverse Engineering is a new research area among software maintenance RE includes activities of understanding the system and recovery info from system Program understanding is the most important subset of Reverse Engineering Discovery of abstraction is key issue Reverse Engineering Design Recovery reproduce all the info for understanding the system Re-documentation provide different views of the system Re-Engineering first phase --understanding the system second phase--forward engineering

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http://www.wiki.reverseengineering.in/ http://www.onlineethics.org/cms/15562.aspx http://books.google.co.in/books/Reverse Engineering: Technology of Reinvention/