Assembly planning

GOOD MORNING

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Novel Approach for Automatic Generation of Assembly

Sequence

ISHAN KOSSAMBE

CONTENTS

# Introduction# Literature Review# Motivation and Problem Statement .# Methodology and Validation.# Implementation.# Result and Discussion.

Introduction

• Assembly

• Need

Introduction

• Hierarchical process

• Information and complex relationships

• Consists of combination of sub assembly

• Assembly accounts for 50% of manufacturing cost

Assembly

Need

• Complex assembly = Number of subassembly

• Assembly planning

• Assembly cost

• Frequent changes in design

• Automatic Assembly planning

LiteratureReview

• Several papers have been published

• Several types of Assembly sequence generation techniques have been formulated

• Automation of Assembly sequence generation

• Reducing human interference

Literature review

• Algorithm based on a mathematical model based on product development process Demoly

• Relational model for assembly based on disassemblyLuiz S. Homem

• Disassembly analysis (stability, fixturing, orientation, refixturing and reorientation count)

Daniel F. Baldwin

• Using haptic information in virtual environmentsJungwon Yoon

• Assembly system design, planning and operations in the presence of product varietyS.J. Hu

• Chaotic particle swarm optimization (stability, assembly time and assembly cost)Y. Wang

• Several optimization techniques used are mathematical models, disassembly, stability and product development .

• Predominantly done manually

• Need to develop better Optimization technique

Outcomes

Problem Statement

• Commercial systems available make use expert assembly sequence planner

• Requires more time and expert knowledge

• Assembly sequence plans generated may not even be the most efficient.

Problem statement

• Extracting information from computer database

• Building of liaisons

• Use of API of CAD Software

• Develop an algorithm

Objective

MethodologyValidation

1. Generation of database

2. Development of Algorithm

3. Implementation

Methodology

• Mating relations in the assembly are required to compute the feasible assembly sequence

• Code is written which extracts the mating relations

• It is stored in the database

Generation of Database

.

MATE

MATERIAL TYPE

PART

Formulation of the Mate Matrix and Assembly Matrix

Start

Extract Information + User Input

Store in Database

Algorithm

Select the Base Component

Select an unassigned Component

Check the Component Relationship

Check for Collision

Check all components have

been assigned

NO

YES

NO

NO

YES

Assembly SequenceGeneration

Finish

Implementation

Implementation

Sl.NO PART Number

1 PULLEY 1

2 COVER PLATE 2

3 BUSH 2

4 DISTANCE BOLT 4

5 NUT 1

6 DUST COVER 1

7 THRUST BEARING 1

8 HOOK 1

9 CROSS HEAD BLOCK 1

10 LOCK PLATE 4

11 HEX SCREW 4

12 NUT M20 4

13 PULLEY PIN 1

14 SPLIT PIN 1

HookCross Head Block

Thrust Bearing

Dust Cover Pulley Pulley

Pin Bush-1 Bush-2 Cover plate-2

Lock Plate-4

Lock Plate-3

Cover Plate-1

Lock Plate-2

Lock Plate-1

Hook X 1 0 0 0 0 0 0 0 0 0 0 0 0

Cross Head Block 1 X 1 1 0 0 0 0 1 1 0 1 1 0

Thrust Bearing 0 1 X 1 0 0 0 0 0 0 0 0 0 0

Dust Cover 0 1 1 X 0 0 0 0 0 0 0 0 0 0

Pulley 0 0 0 0 X 1 1 1 0 0 0 0 0 0

Pulley Pin 0 0 0 0 1 X 1 1 0 0 0 0 0 0

Bush-1 0 0 0 0 1 1 X 1 0 0 0 1 0 1

Bush-2 0 0 0 0 1 1 1 X 1 0 1 0 0 0

Cover plate-2 0 1 0 0 0 0 0 1 X 1 1 0 0 0

Lock Plate-4 0 1 0 0 0 0 0 0 1 X 0 0 0 0

Lock Plate-3 0 0 0 0 0 0 0 1 1 0 X 0 0 0

Cover Plate-1 0 1 0 0 0 0 1 0 0 0 0 X 1 1

Lock Plate-2 0 1 0 0 0 0 0 0 0 0 0 1 X 0

Lock Plate-1 0 0 0 0 0 0 1 0 0 0 0 1 0 X

Mate Matrix

PART RANK

Hook 1

Pulley 2

Cross Head Block 3

Thrust Bearing 4

Cover Plate 5

Pulley Pin 6

Bush 7

Lock Plate 8

Dust Cover 9

Volume Matrix

Part Name Direction to be assembledHook Y

Cross Head Block YThrust Bearing Y

Dust Cover YPulley X

Pulley Pin XBush-1 XBush-2 X

Cover plate-2 XLock Plate-4 ZLock Plate-3 Z

Cover Plate-1 XLock Plate-2 ZLock Plate-1 Z

User Input

Collision Test

LOCK PLATE

PULLEY

Ranking

• If two parts passes the test then we select one part based on the below equation

Score (i) = (X*2) + (Y *1)Where

X= Rank based on Mate MatrixY= Rank based on Volume Matrix

Hook PulleyHook x 1Pulley 0 x

Result & Discussion

1. Hook2. Cross Head Block3. Thrust Bearing4. Dust Cover5. Pulley6. Pulley Pin7. Bush-28. Bush-19. Cover Plate-210. Lock Plate-411. Lock Plate -312. Cover Plate-113. Lock Plate-214. Lock Plate-1

Disassembly Sequence

Assembly Sequence

ResultDiscussion

Result & Discussion

• A new algorithm is developed to generate feasible assembly sequence

• Various information of the assembly is extracted and stored in proper database (matrices)

• Output is a assembly sequence plan• No human interference • Reduction in time and hence money

REFRENCES

• J. L. Nevins and D. E. Whitney, “Concurrent design of product and processes,” McGraw-Hill, New York, 1989.

• U. Rembold, C. Blume, and R. Dillmann, “Computer- integrated manufacturing technology and systems,” Mar-cel Dekker, New York, 1985.

• S. S. F. Smith, “Using multiple genetic operators to re-duce premature convergence in genetic assembly plan-ning,” Computers in Industry, Vol. 54, Iss. 1, pp. 35–49, May 2004.

• E. Zussman, E. Lenz and M. Shpitalni, “An approach to the automatic assembly planning problem”, Annals CIRP, 39(1), pp. 33–36, 1990.

• Dini, G.; Santochi, M., “Automated sequencing and sub-assembly detection in assembly planning”, Annals of the CIRP, Vol.41, 1992.

REFRENCES

• Ong, N.S.; Wong, Y.C., “Automatic Sub-assembly detection from a product Model for disassembly sequence generation”, International journal of Advanced Manufacturing technology, Vol.15, 1999, pp. 425-431.

• Y.Z. Zhang, J. Ni, Z.Q. Lin, X.M. Lai, “Automated sequencing and sub-assembly detection in automobile body assembly planning”, Journal of Materials Processing Technology, 129 (2002) 490–494.

• Arun Tom Mathew; C. S. P. Rao, “A Novel Method of Using API to Generate Liaison Relationships from an Assembly”, Journal of Software Engineering & Applications, 2010, 3: 167-175

• Demoly a,n, Xiu-TianYan, “An assembly oriented design framework for product structure engineering and assembly sequence planning “ journal of Robotics and Computer-Integrated Manufacturing 27 (2011) 33–46

REFRENCES

• Daniel F. Baldwin,Daniel E. Whitney, “An Integrated Computer Aid for Generating and Evaluating Assembly Sequences forMechanical Products”, IEEE transactions on robotics and automation, vol. 7. no. i . february 1991

• Jungwon Yoon , “Assembly simulations in virtual environments with optimized haptic path and sequence”, Journal of Robotics and Computer-Integrated Manufacturing 27 (2011) 306–317

• S.J. Hu, “Assembly system design and operations for product variety”, journal of Manufacturing Technology 60 (2011) 715–733

• Y. Wang, J.H. Liu, “Chaotic particle swarm optimization for assembly sequence planning”, Journal of Robotics and Computer-Integrated Manufacturing 26 (2010) 212–222

THANK YOU -