Reverse Engineering & Its Application

Reverse Engineering• Systematic evaluation of a product with the purpose of replication.

Design of a new part

Copy of an existing part

Recovery of a damaged or broken part

• An important step in the product development cycle.

Importance• We cannot start from the very beginning to develop a new product

every time.

• We need to optimize the resources available in our hands and reduce

the production time keeping in view the customers’ requirements.

• For such cases, RE is an efficient approach to significantly reduce the

product development cycle.

For example: Impeller Pump Design

Suppose there is a impellor pump which had an original pumping

capacity of 20000 cubic feet of water per minute; now, after a year of

use, the pump manufacturing company finds that it is pumping 19000

cubic feet per minute. They need to figure out what happened to that

extra 1 thousand cubic feet in performance. The pump manufacturer

scans the year-old impeller into the CAD system. Once those

measurements are captured, engineers can compare the

measurements taken from the actual impeller against the original, as-

designed part. This helps determine exactly how and where the part

has degraded. With that information in hand, engineers can redesign

the impeller to avoid future loss in pumping capability.

Advantages

• RE typically starts with measuring an

existing object, so that a solid model can be

deduced in order to make use of the

advantages of CAD/CAM/CAE technologies.

• CAD models are used for manufacturing or

rapid prototyping applications.

• Hence we can work on a product without

having prior knowledge of the technology

involved.

Cost saving for developing

new products.

Lesser maintenance costs

Quality improvement

Competitive advantages

RE Process

I. Digitization of the object/

Data Capturing (using

CMM, scanners etc.)

II. Processing of measured

data

III. Creation of CAD model

IV. Prototype

Rapid Prototyping in combination with RE

• A group of techniques to quickly fabricate a scale

model of a physical part or assembly using 3D CAD

data

• Integration of reverse engineering and rapid

prototyping is being used for getting product to the

market quickly by resolving a long-standing conflict

between design and manufacturing

CAD model generation using laser scanner: (a) wooden pattern, (b) cloud of points, and (c) 3D CAD model

a b c

Fabricated RP Model

Areas of Application

Design of a new component

Reproduction of an existing component

Improving quality & efficiency of existing parts

Manufacturing Engineering

• To create a 3D virtual model of an existing physical

part for use in 3D CAD, CAM, CAE or other software

• To make a digital 3D record of own products

• To assess competitors' products

• To analyze the working of a product

• To identify potential patent infringement etc.

Software Engineering

• To extract design & implementation information

• To detect and neutralize viruses and malware

• To determine chemical composition

• To substitute or improve recipes to stimulate or improve the

products performance

Chemical Engineering

Film-Entertainment Industry

• Animated objects are imparted motion using the

reverse engineered human skeletons

Medical Field

• Applications in orthopedic, dental & reconstructive surgery

• Imaging, modeling and replication (as a physical model) of a patient's

bone structure

• Models can be viewed & physically handled before surgery, benefiting

in evaluation of the procedure & implant fit in difficult cases

• Less risk to the patient and reduced cost through saving in theatre

time

Medical Field Applications

Hip Replacement

A Case Study

Adapted from “Reverse engineering in the design of turbine blades-a case study in applying the MAMDP” by Liang-Chia Chen, Grier C.I. Lin

• The large amount of surface data generated from the fast 3D

digitizers is not easily modeled by current CAD/CAM systems.

Inadequate data reduction methods are not only time

consuming, but lose surface characteristic points.

• Consequently, the reconstructed surfaces could lose their true

shape in the design cycle. The time required for reprocessing

in this case would be unacceptable to the manufacturing

industry and thereby be unusable for further steps.

• The study describes how the developed reverse

engineering approach MAMDP was successfully

applied to design of turbine blades and the

existing problems encountered in reverse

engineering processes were overcome.

• MAMDP stands for Modified Adaptive Model-

based Digitizing Process

A 3D initial triangular patch of a subdivided surface patch generated by IVSTP

The surface triangular patch of a subdivided surface patch of the turbine

The surface model of a subdivided surface patch of the turbine blade (before surface trimming)

The surface model of the measured turbine blades.

Generation of initial surface triangular patches of turbine blades

• A charge-coupled device (CCD) camera is used

to rapidly detect the object's position and

measure its surface boundary coordinates, to

establish exploration paths for further

automatic surface digitization of a touch

probe.

• Free-form surface subdivided into an adequate number of

individual surface patches

• 3D stereo detection method is applied to automatically

detect 3D surface boundaries

• Initial triangular patch by applying Triangulation process

• A 3D initial triangular surface patch can be rapidly

generated & used for probe exploration paths in the

following MAMDP

Automatic surface digitization & surface modeling by using the MAMDP

• The surface model is used to calculate the new

exploration points at the approximate

midpoints between the vertices of the initial

triangular patch.

• CMM then automatically digitizes these

exploration targets

• Adaptive approach evaluates the digitizing accuracy by

calculating the deviations between the target points and

the digitized points

• New exploration targets will be generated at the estimated

midpoints between vertices of those triangular patches

where deviations are higher than the user-specified

tolerance

• This iterative digitizing loop will continue until all new

digitized deviations are within the specified tolerance

• Totally 786 surface characteristic points were automatically

digitized by a touch-triggered probe in CMM. The time spent

for this job was 45 min. The digitizing accuracy can be

controlled within 0.25 mm and the maximum fitted error in

the resulting surface model is reduced to 0.030 mm using a

least-squares fitting method.

• To generate a complete CAD surface model of turbine blades,

the individual surface models generated from the MAMDP

have to be merged, according to their geometric relationship.

(Using CAD/CAM package ANVIL5000)

Future Scope & Possibilities

With the advent of RE & RP, we can hope to see

commercial and domestic use of these technologies

to manufacture desired products at home and offices

which will be revolutionary in coming time.

Possibilities of use of this technology is only restricted

by boundaries of human thinking.

• 3D laser scanners as robot eye for scanning objects specially in

space missions.

• Scanning technology can be integrated with mobile

phones/cameras and can be used for 3D printing at domestic level.

• Tissue engineering applications where organs and body parts are

built using inkjet techniques. Layers of living cells are deposited

onto a gel medium or sugar matrix and slowly built up to form

three dimensional structures including vascular systems.

• Availability of 3D printers at every home as is now of the normal

printers.

Around the World…

• 'Wiki Weapon Project' Aims To Create A Gun Anyone Can 3D-

Print At Home.

• The open source Fab@Home project has developed printers

for general use which can use anything squirtable through a

nozzle, from chocolate to silicon sealant and chemical

reactants.

• Some companies offer an on-line 3D printing service open

both to consumers and to industry.

RE of trans tunnel by Macomb College Students

Video

References• Eyup Bagci, Reverse engineering applications for recovery of broken or worn parts

and re-manufacturing: Three case studies, Advances in Engineering Software 40 (2009) 407–418

• Yu Zhang, Research into the engineering application of reverse engineering technology, Journal of Materials Processing Technology 139 (2003) 472–475

• Liang-Chia Chen, Grier C.I. Lin, Reverse engineering in the design of turbine blades}a case study in applying the MAMDP, Robotics and Computer Integrated Manufacturing 16 (2000) 161-167

• http://en.wikipedia.org/wiki/Reverse_engineering• http://www.asme.org/kb/news---articles/articles/computational-methods---

modeling/the-rise-of-reverse-engineering• R. Schenker, Novel combination of RE & RP in medicine, South African Journal of

Science, 95, August 1999• 'Wiki Weapon Project' Aims To Create A Gun Anyone Can 3D-Print At Home-

http://www.forbes.com/sites/andygreenberg/2012/08/23/wiki-weapon-project-aims-to-create-a-gun-anyone-can-3d-print-at-home/

Thank You!