SELECTION OF MATERIAL HANDLING EQUIPMENT FOR FLEXIBLE MANUFACTURING SYSTEM USING FAHP

International Journal of Recent advances in Mechanical Engineering (IJMECH) Vol.5, No.1, February 2016
DOI : 10.14810/ijmech.2016.5103 25
SELECTION OF MATERIAL HANDLING
EQUIPMENT FOR FLEXIBLE MANUFACTURING
SYSTEM USING FAHP
Surinder Kumar1
and Tilak Raj2
1,2
Department of Mechanical Engineering, YMCA University of Science and
Technology, Faridabad, Haryana, India
ABSTRACT
Material handling equipment plays an important role in the design and development of advance
manufacturing systems (AMS) like flexible manufacturing systems. Material handling equipments affects
the performance and productivity of these advance manufacturing systems. So it becomes very important to
select a right kind of equipment while designing the high end manufacturing systems like FMS. In this
paper an attempt has been made to select the most appropriate material handling equipment for the design
and development of FMS. The proposed model has been build on the basis of material handling attributes
and sub attributes which are critical for material handling equipment selection.
KEYWORDS
Analytical hierarchy process, material handling equipments, multi criteria decision making, optimization
and flexible manufacturing systems.
1. INTRODUCTION
Material handling technology is becoming the most important criteria to all type of the
productive and non productive businesses operating in today’s competitive society. So material
handling equipment selection is an important function of a material handling system. Use of
proper material handling equipment can enhance the production process, and improves system
flexibility (Tuzkaya et al., 2010). Today’s dynamic and global competition in the market due to
the rapid growth in technology shortened product life cycle and high quality product expectation
by the customers at lowest price makes the concerns more competitive at national and
international level (Raj et al. 2008). To overcome these difficulties importance of material
handling equipments cannot be ignored. In this modern era of technology, availability of wide
range of material handling equipment options, selection of material handling equipment is a
complex and tedious task for the decision maker. Therefore, MHE selection problem can be
considered as multiple criteria decision making (MCDM) problem.
According to the Sujono and Lashkari (2007) in a typical manufacturing facility material
handling accounts for 25% of all employees, 55% of all company space, 87% of the production
time and 15-75% of the total cost of the product. Therefore, material handling is considered as a
first and active element of the advance manufacturing system. In the current there are many
MCDM techniques used for supporting the decision maker views in numerous and conflicting
evaluations. Such type of methods can also be used for ranking and conflicting attributes
solutions. The most popular MCDM methods are analytic hierarchy process (AHP), analytic
network process (ANP), data envelopment analysis (DEA), simple multi attribute ranking
(SMART) and TOPSIS etc. (Goodwin and Wright, 2009).

26
The material handling system (MHS) play a crucial and effective role in flexible manufacturing
systems (FMS) environment. Basically FMS is an integrating computer controlled system of
automated material handling equipments and numerically controlled (NC) machine tools which
can simultaneously process medium sized volumes of a variety of parts. The key characteristics
of FMS are to meet the production requirement by producing variety of parts and volume through
proper utilization of machines, space, reduced labor cost, flexibility and high quality products
with minimization of manufacturing lead time and the parts can also be produced at lower cost by
integrating hardware and software of material handling equipments like automated guided vehicle
system (AGVS), industrial robotics, automated conveyors, fork lift trucks and cranes etc. A
technique is required to evaluate material handling equipments ranking to deal with fuzzy
conflicting criteria attributes like automation, cost and load carrying capacity etc for different
material handling systems. This paper predicts the material handling equipment to be selected for
the purpose of material handling in FMS environment using fuzzy analytical hierarchical process
(FAHP).
The main objectives of this research are as follows:
 To identify and rank the attributes which are supportive in the selection of material
handling equipment’s.
 To establish relationship between these attributes through FAHP model.
 To identify most significant material handling attributes on the basis of developed FAHP
model.
 To suggest directions for future research.
The paper has been organized as follows:
In the remainder of this paper, literature review on material handling equipment in FMS
environment is presented in section 2. Fuzzy Analytic Hierarchy Process (FAHP) Method is
discussed in section 3. Section 4 discusses the methodology for the selection of material handling
equipment. This is followed by an example in section 5. At last, discussion and conclusions are
presented in section 6 and 7 respectively.
2. LITERATURE REVIEW
It is evident from the literature that material handling (MH) is an activity which is used to provide
the right amount of the right material at the right place, at the right time, in the right sequence, in
the right position and at the right cost. Due to the high competition selection of material handling
equipment has become a very complex and tedious task for the decision makers. Hence proper
selection of appropriate material handling equipment has become a most important parameter for
modern manufacturing concerns (Tompkins, 2010). Many studies have been conducted to address
the material handling equipment selection problem. In this regard many researchers have applied
various models to predict the selection of the various materials handling equipment’s like integer
optimization, simulation and modeling, fuzzy genetic support system, holonic, knowledgebase,
SAW, TOPSIS, Grey AHP, AHP/M-GRA and dynamic programming. Chan et al. (2001)
presented a material handling equipment selection model for the development of an intelligent
system called material handling equipment selection advisor (MHESA). Bhattacharya, et al.
(2002) discusses the method for material handling equipment selection under multi criteria
decision making (MCDM) environment. Chu & Lin. (2003) have developed a fuzzy TOPSIS
method for robot selection. Kulak et al. (2004) have selected multi-attribute material handling
equipment selection using Information Axiom. Babiceanu et al. (2004) provided a framework for
the control of automated material-handling systems using the holonic manufacturing approach.
Kulak (2005) developed a decision support system named fuzzy multi-attribute material handling

27
equipment selection. Bhattacharya et al. (2005) provided an integrated model combining AHP
and QFD for the industrial robot selection problem. Chakraborthy and Banik (2006) used AHP
technique in selecting the optimal material handling equipment for a specific material handling
equipment type. Sujono and Lashkari (2007) advocated a method for simultaneously determining
the operation allocation and material handling system selection in a flexible manufacturing
environment with multiple performance objectives. Lau and Woo (2008) proposed an agent-
based dynamic routing strategy for automated material handling systems. Onut (2009) used fuzzy
ANP and fuzzy TOPSIS methods for selecting material handling equipment. Dragan and
Vladislav (2009) describe a multi-attribute selection method for materials handling equipment.
Tuzkaya et al. (2010) presented an integrated fuzzy multi-criteria decision making methodology
for material handling equipment selection problem and an application. Athawale and
Chakraborty (2010) advocated a combined TOPSIS-AHP method for conveyor belt selection.
Heragu, et al. (2011) used an analytical model for analysis and selection of automated material
handling systems for warehouse. Maniya and Bhatt (2011) described a multi-attribute selection of
automated guided vehicle using the AHP/M-GRA technique. Athawale et al. (2012) developed a
ranking method for the selection of industrial robots. Bairagia (2013) also used a holistic
approach based on incremental analysis for the performance evaluation of material handling
equipment. Vatansever and Kazançoğlu (2014) have advocated integrated usage of fuzzy multi
criteria decision making techniques for machine selection problems and an application.In this
study, FAHP has been used to select the appropriate material handling equipment (MHE).
3. FUZZY ANALYTIC HIERARCHY PROCESS (FAHP) METHOD
The Fuzzy Analytic Hierarchy Process (FAHP) is an advanced multi-criteria decision-making
approach and it was introduced by Saaty (1994 and 2000). Bevilacqua et al., 2004 advocated that
AHP is a useful and flexible multi – criteria decision – making (MCDM) tool which deals with
complex problems of qualitative and quantitative aspects of a problem in to a hierarchy.
Nowadays, there are many MCDM methods are in use. The combination of Fuzzy AHP is
broadly used for solving complex decision making problems. Decision makers use a fundamental
1-5 scale of absolute numbers to make pair wise comparison in the Saaty’s approach. The
advantage of fuzzy AHP method is that it provides to work at certain intervals in judgments
rather than certain absolute values. Due to the popularity of this method rather than AHP decision
makers use natural linguistic as well as certain numbers to evaluate criteria and alternatives.
FAHP method is frequently used due to ability of solving the complex problems in different areas
such as supplier selection and evaluation (Sun, 2010; Chamodrakas and Martakos, 2010;
Krishnendu et.al., 2012; Kılınçcı and Önal, 2011); evaluating performance of national R&D
organizations (Jyoti and Deshmukh, 2008); optimal hospital locatin selection; marketing strategy
selection (Mohaghar et.al., 2012) and personnel selection problems (Güngör et.al., 2009).
In this method, fuzzy numbers are used for problem solution instead of crisp numbers. Chen and
Hwang (1992) have proposed this method. The steps used in this method are as follows:
Step 1: Conversion of linguistic terms in to fuzzy numbers.
First of all linguistic term will be converted into their corresponding fuzzy numbers. Particularly
for this process we consider a five point conversion scales to show the conversion of linguistic
terms in to fuzzy numbers. Wenstop et. al. (1976) have also used a conversion scales method for
synthesizing and modifying their research works.
Step II: Conversion of Fuzzy Numbers in to Crisp Scores.
This step uses a fuzzy scoring approach for conversion in to fuzzy ranking (Chen1985).
Conversion process of fuzzy number “M” into crisp score is as Follows:

28
( )
0, other
,0 1,
wise
MAX x
x x

 

 
 
 
( )
1- ,0 1,
0, otherwise
Min x
x x

 







The value of Max and Min fuzzy numbers can be calculated for the comparison purpose which is
as follows:
𝜇 𝑅 (𝑀1) =𝑆𝑢p [𝜇𝑚𝑎𝑥 (𝑥) ^ 𝜇 𝑀1 (𝑥)]
μ 𝐿 (𝑀1) =𝑆𝑢p [𝜇𝑚𝑖𝑛 (𝑥) ^ 𝜇 𝑀1 (𝑥)]
Total score of fuzzy number (Mi) is defined as:
𝜇 𝑇 (𝑀1) = [𝜇 𝑅 𝑀1 + 1 − 𝜇𝐿 𝑀1] /2
Step III: Demonstration of the conversion method.
In this process, we have used a 5- point scale for the conversion of fuzzy number into crisp scores
by utilizing the linguistic terms like low, below average, average, above average and high as
shown in Figure 1.
Figure 1. Linguistic terms to fuzzy numbers conversion (5-point scale)
Table 1. Conversion scale for linguistic variable to fuzzy number (5-point scale)
Then right, left & total score of fuzzy number M are calculates as given below:
Linguistic Variables Fuzzy Numbers
Low M1
Below average M2
Average M3
Above average M4
High M5

29
𝜇 𝑅 (𝑀1) =𝑆𝑢p [𝜇𝑚𝑎𝑥 (𝑥) ^ 𝜇 𝑀1 (𝑥)]
μ 𝐿 (𝑀1) =𝑆𝑢p [𝜇𝑚𝑖𝑛 (𝑥) ^ 𝜇 𝑀1 (𝑥)]
Total score of fuzzy number (Mi) is defined as:
𝜇 𝑇 (𝑀1) = [𝜇 𝑅 𝑀1 + 1 − 𝜇𝐿 𝑀1] /2
Crisp values can also be calculated from Figure1 for their fuzzy Numbers M1, M2 M3, M4 and
M5 as follows:
 
1-x = 0
1 (0.3 )
, 0.0 x 0.3
0.3
M x x


 
 
 
( 0.7)
5 , 0.7 x 1.0
0.3
1, 1
x
M x
x




  

 
The right, left and total score for fuzzy numbers can be calculated by using the following
formulas as given below:
𝜇𝑅 (𝑀1) =𝑆𝑢p [𝜇𝑚𝑎𝑥 (𝑥) ^ 𝜇𝑀1 (𝑥)] =0.23
μ𝐿 (𝑀1) =𝑆𝑢p [𝜇𝑚𝑖𝑛 (𝑥) ^ 𝜇𝑀1 (𝑥)] =0.1
𝜇𝑇 (𝑀1) = [𝜇𝑅 𝑀1 + 1 − 𝜇𝐿 𝑀1] /2 =0.115
 
0.5
,0.5 0.75
0.25
4
, 0.75 x 1.0
(1.0 )
(0.25)
x
x
x
M x

 
    



 
( 0)
,0 x 0
(0.
.3
0
5
.25
2
, 0 x 0.5
)
(0.25)
x
x
x
M


 
 
  

  (0.7
(0 0.3)
,0.3 x 0.5
0.2
3
, 0.5 x 0
)
(0.2)
.7
x
M x

 
 

 


30
Calculated Crisp values of right, left and total Score of fuzzy numbers M1, M2, M3, M4 and M5
are shown below in Table 2:
Table 2. Show right left & total score for M1, M2, M3, M4 and M5.
Table 3. Show linguistic variable along with their fuzzy number and crisp score.
4. METHODOLOGY
Fuzzy Analytic Hierarchy Process (FAHP) is a simple multi-criteria decision-making approach to
deal with complex, unstructured and multi-attribute problems. It is a most creative decision
making tool used in modeling of complex problem. In this approach, identification of the decision
hierarchy is the key aspect of FAHP. This process is essential for the formalization of a complex
problem in a hierarchical structure.To solve a decision problem with FAHP, there are some steps
which are defined below:
1. Determine objective and evaluation of attributes.
2. Determine attribute importance of different attributes with respective to the objective.
3. Compare the alternatives pair wise with respective to others.
4. Determine overall or composite performance scores for the alternatives.
5. Ranking the alternatives.
6. Choosing the highest ranking from the set of alternative
Step 4.1: Determine the objective and evaluate attributes.
Develop a hierarchical structure with an objective at the top level, the attributes at the middle
level and the alternatives at the bottom level.
Fuzzy
Number
μR μL μT
M1 0.23 1.0 0.115
M2 0.39 0.8 0.295
M3 0.58 0.59 0.495
M4 0.79 0.4 0.695
M5 1.0 0.23 0.895
Linguistic
Variables
Fuzzy
Numbers
Crisp
score
Low M1 0.115
Below average M2 0.295
Average M3 0.495
Above average M4 0.695
High M5 0.895

31
Objective
Attributes
Alternative
Figure 2. The hierarchy structure of the decision-making problem
Step 4.2: Determine the relative importance of different attributes with respect to the objective.
In this step a decision matrix is developed on the basis of expert opinions and their judgments. An
attribute compared with it is always assigned value as 1. So that the main diagonal entries of the
pair wise comparison matrix can be entered as 1 for calculation purpose as shown in Table 4.
 Assuming M attributes, the pair-wise comparison of attribute i with attribute j yields a square
matrix BM x M where aij denotes the comparative importance of attribute i with respect to
attribute j. In the matrix, bij = 1 when i = j and bji = 1/ b
Table 4. Scale of relative importance
Scale of
importance
Linguistic variable Explanation for attributes
1 Equal important Two attributes are equally important
3 Moderate important One attribute is moderately influential over the
other
5 Strongly important One decision attribute is strongly important over
the other
7 Very important One decision attribute has significantly more
influence than the other.
9 Extremely important One attribute is absolutely important over the
other
2,4,6,8
Reciprocals
Compromise importance/
intermediate importance
between two adjacent
judgement1,3,5,7 and 9
Judgment values between equally, moderately,
strongly, very strongly and extremely. If v is the
judgment value when I is compared to j,than 1/v
is the judgment value when j is compared to i.
Table 5. Random Index (RI) values (Saaty 2004)
Attributes (m) 1 2 3 4 5 6 7 8 9 10
RI Values 0.00 0.00 0.58 0.90 1.1
2
1.2
4
1.3
2
1.4
1
1.4
5
1.4
9
Automation
Cost Load carrying
capacity
Automatic
Conveyor
Robot AGV
Selection of Material
Handling Equipment

32
 Calculate geometric mean: - It is calculated by multiplying the elements of each row and
then dividing by size of matrix. Then, Total geometric mean is calculated by adding
geometric mean for each row.
1
1
m m
i ij
j
GM a

 
  
 

(1)
1
j
j m
ii
GM
w
GM


(2)
 Calculate normalized weight: - It is calculated for each row by dividing the geometric
mean of each row by total geometric mean and then weights obtained are arranged in a
matrix denoted by Q2.
 Calculate matrices Q3 and Q4
Q3 = Matrix Q13X1 X Matrix Q23X1 Where Q1 = relative importance matrix
Q2 = normalized Matrix.
Q4 = Matrix Q33X1 / Matrix Q23X1
Where Q2 = [w1, w2. . . wj ]T.
 Calculate λ max = Sum of Q4 elements / No. of Q4 elements
 Calculate consistency Index: CI = (λ max-m) / (m-1) Where m = Size of matrix.
 Calculate consistency ratio: CR = CI / RI
Where RI is random index, which is already specified for specific number of criteria. If value of
CR is less than 0.1 then, weights are consistent.
Step 4.3 This step is used to compare the alternatives pair wise with respect to others and shows
the satisfaction level of each attribute.
If there is N number of alternatives, then there will be M number of N x N matrices of judgments
since there are M attributes. Develop pair wise comparison matrices by using a scale of relative
importance and enter the judgements by using the fundamental scale of the AHP. The remaining
procedure is same as shown in step 3.2.
For AHP model, both the relative and absolute modes of comparison can be utilized. The relative
mode is used in those cases when decision makers have its prior knowledge of the attributes for
different alternatives or when objective data attributes for different alternatives is not available.
Similarly the absolute mode is used when data of the attributes for different alternatives are
readily available. In case of absolute mode, the value of CI is always equal to 0, since the exact
values of consistency are used in comparison matrices.
Step 4.4 This step is used for finding the overall or composite performance scores for the
alternatives by multiplying the relative normalized weight (wj) of each attribute with its
corresponding normalized weight value for each alternative and summing up over all attributes
for each alternative.

33
Quantitative attributes are generally deals with some selection problems. If there is any difficulty
arises in qualitative attributes or for the qualitative attributes where quantitative attributes values
are not available. Generally in such type of problems a ranked value judgment on a fuzzy
conversion scale is adopted. A fuzzy set theory is used for deciding the values of its attributes as
linguistic terms, its conversion into corresponding fuzzy numbers and than its crisp scores.
According to the Chen and Hwang (1992) a numerical approximation method can also be used
for conversion of linguistic terms to their corresponding fuzzy numbers. Here a 5-point
conversion scale is used as shown in Table 8. In this paper we have considered a 3 point scale for
better understanding and representation purpose by using equation 1 as shown in Table 6 and 7.
Table 9 has been used to show the 3 different criteria for their fuzzy AHP. This helps the users in
assigning the values.
Table 6. Crisp value of fuzzy numbers in 3- point scale
Material
handling
Equipments
(Variables)
Material Handling Equipment Selection
(Attributes)
Automation Load Carrying
Capacity
Cost
Auto. Conveyor 0.75 0.2323 1
Robot 0.66 1 0.553
AGV 0.1 0.1284 1
Table 7. Decision making matrix for material handling equipments
Material handling
Equipments
(Variables)
(Attributes)
Capacity
Cost
Auto conveyor 0.75 0.2323 1
Robot 0.66 1 0.553
AGV 0.1 0.1284 1
Table 8. Linguistic variable along with their fuzzy number & crisp score.
5. ILLUSTRATIVE EXAMPLE
Now, an example is considered to demonstrate and validate the FAHP method for selection of
material handling equipments in an industrial application. The detailed steps involved in the
application of the FAHP method for selecting optimal material handling equipment are described
below:
Linguistic Variables Fuzzy Numbers Crisp score
Low M1 0.115
Below average M2 0.295
Average M3 0.495
Above average M4 0.695
High M5 0.895

34
For this study we choose material handling equipments attributes as an input parameters a shown
in Table 9.
Table 9. Various attributes and alternatives for Fuzzy AHP.
Material handling
Equipments
(Variables)
(Attributes)
Capacity
Cost
Automated
Conveyor
Low High Average
Robot High Average High
AGV High High High
Step 1: The objective is to select right material handling equipments amongst the number of
available material handling equipments. Since for this study we choose only three linguistic
variables i.e. Low, Average and High on a three point scale as shown in Table 10 and Table 11.
Table 10. Linguistic variables with fuzzy numbers.
Linguistic Variables Fuzzy Numbers
Low M1
Average M2
High M3
These fuzzy numbers are then converted in to crisp score by using Table 2 and Table 3.
Table 11. Crisp scores and fuzzy numbers.
Linguistic Variables Fuzzy Numbers Crisp Score
Low M1 0.115
Average M2 0.495
High M3 0.895
Based on above crisp score decision making matrix (DMM) has been formed which is as follows
0.115 0.895 0.495
0.895 0.495 0.895
0.895 0.895 0.895
 
 
 
 
 
Step 2: Calculating the relative importance of different attributes with respect to the objective:
These attribute requires higher values as a beneficial factor. To make comparative decisions, the
relative importance of all possible pairs of attributes with respect to the overall objective of
selecting the right material handling equipments is decided. These are arranged into a matrix form
of, Q13x3. The judgments on the attributes are entered in the form of matrix as shown in Table 4.
Consistency Check
Construct Relative importance matrix. Each attribute is compared with other attributes and
weights are assigned based on expert reasoning, using table 4 Diagonal elements are always 1
because compared with it themselves. It is denoted by Q.

35
Find out the relative normalized weight (wi
) of each attributes by calculating the geometric mean
of the i
th
row and normalizing the geometric means of rows in the comparison matrix:
 Geometric mean calculation:
Q2 =
 Normalized Weight calculation:
W1 = GM1 / GM =2.466 / 3.80 = 0.649
W2 = GM2 / GM = 0.464 / 3.80 = 0.1210
W3 = GM3 / GM = 0.870 / 3.80 = 0.229
Matrix Q23X1 is written as:
Q23x1=
0.1210
0
0.649
.229
 
 
 
 
 
 
 
 
 
 Calculate Q3
Matrix Q33X1 is written as
Q3 = Q1XQ2
GM1 = === = (1 X 5 X 3) / 3 = 2.466
GM2 = (1/5 X 1 X 1/2) / 3 = 0.464
GM3 = (1/3 X 2 X 1) / 3 = 0.870
Total GM = GM1+GM2+GM3 = 3.80
1 5 3
1
1/ 5 1 1/ 2
1/ 3 2 1
Automation LoadCarryingcapacity Cost
AutoConveyor
Q
Robot
AGV
 
 
 
  
 
 
 
 
 

36
Q33X1 =
1 5 3 1.914
*
0.649
1/ 5 1 1/ 2 0.1210 0.36
1/ 3 2 1 0.229 0.678
Automation LoadCarryingcapacity Cost     
     
     
     
     
     
     
     
     
 Calculate Q4
Q4=Q3/Q2
Q43x1=
1.914
0.36
0.678
 
 
 
 
 
 
 
 
 
/
0.1210
0
0.649
.229
 
 
 
 
 
 
 
 
 
=
2.975
3.
2.949
0818
 
 
 
 
 
 
 
 
 
 Calculate λmax
λmax = Total sum of Q4 / Size of Q2 = 3.001/3 =3.001
 Calculate CI
CI = λmax-m / m-1, m = size of matrix
= (3.001 – 3 ) / (3-1) = 0.0005
 Calculate CR
CR = CI / RI, for 3 criteria the value of RI=0.00096
The RI is obtained from Table 2 for three attributes used in the decision making in the present
example and it is 0.58.
The CR is calculated as CR = CI/RI and in the present example this ratio is 0.00096 which is less
than the allowed CR of 0.1 and hence the value is acceptable. Thus, there is a good consistency in
the judgments and decision matrix is right.

37
Step 3: Pair - Wise Comparison: Pair wise comparison of alternative to alternative is performed
for each criterion as below:
I) Pair wise comparison matrix for criteria Automation
 Geometric Mean Calculation:
 Normalized Weights Calculation:
W1 = GM1 / GM =.7623/3.05 = 0.2530
W2 = GM2 / GM = 1.2182/3.05 = 0.4840
W3 = GM3 / GM = 1.0767/3.05 = 0.3520
Q23X1 =
0.4848
0
0.2530
.3520
 
 
 
 
 
 
 
 
 
 Calculate Q3
Matrix Q33X1 is written as Q33X1= Q13X1 x Q23X1
GM1= ===
=
(1 X 0.495 X 0.895) / 3 = 0.7623
GM2 = (1/0.495 X 1 X 1/0.895) / 3 = 1.2182
GM3 = (1/0.895 X 1/0.895 X 1) / 3 = 1.0767
1 0.495 0.895
1
1 / 0.495 1 0.895
1 / 0.895 1 / 0.895 1
AutoConveyor Robot AGV
AutoConveyor
Q
Robot
AGV
 
 
 
  
 
 
 
 
 

38
Q33X1 =
1 0.495 0.895 0.7614
*
1/ 0.495 1 0.895 0.4848 1.2167
1/ 0.895 1/ 0.895 1 0.3520 1.075
0.2530
2
     
     
     
     
     
     
     
     
 Calculate Q4
Matrix Q43X1 is written as Q43X1= Q33X1 / Q23X1
Q43X1=
0.7614
1.2167
1.0752
 
 
 
 
 
 
 
 
 
/
0.4848
0
0.2530
.3520
 
 
 
 
 
 
 
 
 
=
3.005
3
3.074
.053
 
 
 
 
 
 
 
 
 
 Calculate λmax
λmax = Total sum of Q4 / Size of Q4 = 9.132 / 3 = 3.044
 Calculate CI
= (3.044 – 3 ) / (3-1) = 0.022
 Calculate CR
CR = CI / RI for 3 criteria the value of RI chosen from Table 2.is 0.58.
CR = 0.022/0.58
CR = 0.0379
The value of CR is 0.0379 which is less than the allowed value of CR (0.1), therefore the
value is acceptable. Hence Weights are consistent.
II) Pair wise comparison matrix for criteria Robot
1 0.895 0.115
1
1/ 0.895 1 0.115
1/ 0.115 1/ 0.115 1
AutoConveyor Robot AGV
AutoConveyor
Q
Robot
AGV
 
 
 
  
 
 
 
 
 

39
 Geometric Mean Calculation:
 Normalized Weights Calculation:
W1 = GM1 / GM = 0.4686/5.2012 = 0.090
W2 = GM2 / GM = 0.5046/5.2012 = 0.0970
W3 = GM3 / GM = 4.2280/5.2012= 0.8128
Q23X1 = 0.0970
0.
0.090
8128
 
 
 
 
 
 
 
 
 
 Calculate Q3
Q33X1 =
1 0.895 0.115 0.2701
*
1/ 0.895 1 0.115 0.0970 0.2908
1/ 0.115 1/ 0.1
0.0
15 1 0.812
9
8 2. 3
00
4 8
     
     
     
     
     
     
     
     
 Calculate Q4
GM1= == =
=
(1 X 0.895 X 0.115) / 3 = 0.4686
GM2 = (1/0.495 X 1 X 1/0.895) / 3 = 0.5046
GM3 = (1/0.895 X 1/0.895 X 1) / 3 = 4.2280

40
Q43X1 =
0.2701
0.2908
2.438
 
 
 
 
 
 
 
 
 
/
0.0970
0
0.0900
.8128
 
 
 
 
 
 
 
 
 
=
2.997
3
3.001
.002
 
 
 
 
 
 
 
 
 
 Calculate λmax :
λmax = Total sum of Q4 / Size of Q4 = 9.00 / 3 = 3.00
 Calculate CI :
= (3.0 – 3 ) / (3-1) = 0.00
 Calculate CR
CR= CI / RI for 3 criteria the value of RI chosen from Table 2.is 0.58.
CR = 0/0.58
CR = 0.0
The value of CR is 0.0 which is less than the allowed value of CR (0.1), therefore the value is
acceptable. Hence Weights are consistent.
I1I) Pair wise comparison matrix for criteria Cost
Geometric Mean Calculation
 Normalized Weights:
W1 = GM1 / GM = 0.7910/3.0468= 0.2660
W2 = GM2 / GM = 1.2182/3.0468= 0.4980
GM1 = ===
=
(1 X 0.495 X 1) / 3 = 0.7910
GM2 = (1/0.495 X 1 X 1/0.895) / 3 = 01.2182
GM3 = (1 X 1/0.895 X 1) / 3 = 1.0376
1 0.495 1
1
1 / 0.495 1 0.895
1 1 / 0.895 1
Automation LoadCarryingcapacity Cost
AutoConveyor
Q s
Robot
AGV
 
 
 
  
 
 
 
 
 

41
W3 = GM3 / GM =1.0376/3.0468= 0.3406
Q23X1 = 0.3998
0
0.2596
.3406
 
 
 
 
 
 
 
 
 
 Calculate Q3
Q33X1=
1 0.495 1 0.7981
*
1/ 0.495 1 0.895 0.3998 1.229
1 1/ 0.895 1
0.259
0.3406 1.0469
6
     
     
     
     
     
     
     
     
 Calculate Q4
Q43x1=
0.7981
1.229
1.0469
 
 
 
 
 
 
 
 
 
/
0.3998
0
0.2596
.3406
 
 
 
 
 
 
 
 
 
=
3.0743
3.0740
3.0736
 
 
 
 
 
 
 
 
 
 Calculate λmax:
Λmax = Total sum of Q4 / Size of Q4 = 9.221 / 3 = 3.073
 Calculate CI
= (3.073 – 3) / (3-1) = 0.036

42
 Calculate CR:
CR = CI / RI,
CR = 0.036/0.58
CR = 0.062
for 3 criteria the value of RI chosen from Table 2.is 0.58.
The value of CR is 0.062 which is less than the allowed value of CR (0.1), therefore the value is
acceptable. Hence Weights are consistent.
Step: 4
Matrix is formed for pair wise comparison based on results i.e. weights received from step 4 for
different criteria
Decision of material handling equipments is based on the Higher Ranking
Based on their final ranking received through pair wise comparison between alternatives of each
attribute A3 (AGV) is a best material handling equipment.
6. DISCUSSION
The main aim of this research is to develop a frame work for the selection of appropriate material
handling equipment amongst the number of available material handling equipment’s under the
given conditions. For this purpose, a model has been prepared to analyze the interaction between
various attributes of material handling equipments. This frame work will be useful in
understanding the hierarchy of actions to be taken for the selection of different material handling
equipment’s on the basis of these attributes. The management and production managers of the
manufacturing field can take the idea from these attributes in understanding their relative
importance. This model has been developed by using FAHP approach. FAHP is an effective
problem solving multi criteria decision making technique. The decision problem may contain
various attributes that need to be evaluated by linguistic variables. Fuzzy numbers numerical
Material handling
Equipments
Results Ranking
A1 0.2319 R3
A2 0.3617 R2
A3 0.4047 R1
0.2319
0.2530 0.090 0.2660 0.649
1
0.3617
0.4840 0.0970 0.4980 0.121
0.4047
0.3521 0.8128 0.3406 0.229
Q
 
     
     
     
      
     
     
     
     
   

43
values of linguistic variables are used for evaluation. Hence Fuzzy AHP (FAHP) is a well suited
technique to deal with such situations very well. The importance of material handling equipments
variables is as under:
 Attributes, automation, cost and load carrying capacities are the main attributes of the
material handling equipments which has more influence on alternatives.
 The relationship between the attributes and alternatives of material handling equipment’s
can be understood by visualization of Figure 2.
 The automated conveyors can only be used for material handling for specific path and
application .whenever the AGVs can move freely to carry the material within the layout.
 The automated conveyors cannot be easily interfaced with all equipments and machinery
used for manufacturing facility whenever AGV can be easily interface with
manufacturing facilities.
 Movement of the robots is limited between one work station to the other for material
handling. They generally move about their own axis whenever AGVs can easily move
between the required work stations.
 Robots have small and limited load carrying capacity whenever the AGVs can carry the
heavy load easily.
7. CONCLUSION
In this paper Fuzzy AHP approach has been used for the evaluation of different material handling
equipment’s for the FMS environment under the given conditions. The example cited in the paper
consists of 3 attributes along with 3 alternatives. This simple example has been presented for the
demonstration of proposed methodology.
In this paper, a pair wise comparison was carried out between the various alternatives for each
considered attribute and finally weights were obtained. These weights are then utilized for
deciding the ranking of material handling equipments as A1 (Automatic Conveyor), A2 (Robot)
and A3 (AGV). In the considered example, it is found that the material handling equipment A3
(AGV) is the best alternative among the considered alternatives.
The major limitations of FAHP are as follows:
 Pair wise comparisons are based on the expert opinions and this may lead to biasness.
 Application of Fuzzy AHP is inappropriate in general decision making.
 FAHP fails to capture the uncertainty in the operational environment.
 Decision is based on the comparison ratios. Moreover, uncertainties are used by the
decision maker.
 Absolute values are not sufficient to make real life decisions.
So, in future, following work may be carried out:
 More numbers of attributes can be identified for developing FAHP model.
 A comparison can also be executed with other fuzzy MCDM techniques like fuzzy
TOPSIS approach which will be beneficial in enhancing the production and flexibility of
the organization.
 Sensitivity analysis can be carried out to know the effect of different criterion on the
material handling equipment selection.

44
REFERENCES
[1] Athawale, V. M., and Chakraborty, S. (2010) ‘A combined topsis-ahp method for conveyor belt
material selection’, Journal of the Institution of Engineers (India), Part PR: Production Engineering
Division,90 (MARCH), 8-13.
[2] Athawale, V. M., Chatterjee, P., and Chakraborty, S. (2012) ‘Selection of industrial robots using
compromise ranking method’,. International Journal of Industrial and Systems Engineering, Vol.11,
No.1-2, pp.3-15.
[3] Babiceanu, R.F., Chen, F.F., Sturges, R.H.(2004) ‘Framework for control of automated material-
handling systems using holonic manufacturing approach’, International. Journal of Production
Research, Vol. 42, No.17, pp. 3551-3564.
[4] Bairagia Bipradas, Balaram Deyb and Bijan Sarkarc (2013) ‘Incremental analysis for the performance
evaluation of material handling equipment: A holistic approach, Uncertain Supply Chain
Management, Vol.1, pp. 77–86.
[5] Bevilacqua, M., D’Amore, A., and Polonara, F. (2004) ‘A Multi-Criteria Decision Approach to
Choosing The Optimal Blanching-Freezing System’, Journal of Food Engineering, Vol.63, pp.253-
263.
[6] Bhattacharya, A., Sarkar, B. and Mukherjee, S.K.(2002) ‘A holistic multi-criteria approach for
selecting machining processes, 30th International Conference on Computers & Industrial
Engineering, Tinos Island, Greece, pp.83 – 88.
[7] Bhattacharya, A., Sarkar, B., and Mukherjee, S. (2005) ‘Integrating AHP with QFD for robot
selection under requirement perspective’, International Journal of Production Research, Vol. 43,No.
(17), pp.3671–3685.
[8] Chakraborty, S. and Banik, D.(2006) ‘ Design of a material handling equipment selection model
using analytic hierarchy process’, International Journal of Advanced Manufacturing Technology,
Vol.28, No. 11–12, pp.1237–1245.
[9] Chamodrakas, I., Batis, D. and Markatos, D. (2010) ‘Supplier Selection in Electronic Market Places
Using Satisfying and Fuzzy AHP, Expert Systems with Applications, Vol.37, pp.490-498.
[10] Chan, F.T.S., Ip, R.W.L., and Lau, H. (2001) ‘Integration of expert system with analytic hierarchy
process for the design of material handling equipment selection system’, Journal of Materials
Processing Technology,Vol. 116, No. 2, pp.137–145.
[11] Chen, S.J. and Hwang, C.L. (1992) ‘Fuzzy multiple attribute decision making methods and
Applications,’ Lecture notes in Economics and Mathematical Systems. Berlin: Springer-Verlag.
[12] Dragan, K. and Vladislav, K. (2009) ‘Multi-attribute selection method for materials handling
[13] Equipment’, International Journal of Industrial Systems Engineering, Vol.4, No.2, pp.151–173.
[14] Goodwin,P. and Wright,G (2009) ‘Decision Analysis for Management Judgments’, 4the edition,
Chichester, UK: Wiley.
[15] Güngör, Z. Serhadlıoğlu, G. and Kesen, S. (2009) ‘A Fuzzy AHP Approach to Personnel Selection
Problem, Applied Soft Computing, Vol.9, pp. 641-646.
[16] Heragu, S.S., Xiao, C., Krishnamurthy, A. and Malmborg, C. J. (2011) ‘Analytical Models for
Analysis of Automated Warehouse Material Handling Systems, International Journal of Production
Research, Vol. 1, No. 29
[17] Jyoti, B.D.K and Deshmukh, S.G. (2008) ‘Evaluating Performance of National R&D Organizations
Using Integrated DEA-AHP Technique, International Journal of Productivity and Performance
Management, Vol.57, pp. 370-388.
[18] Klınçcı, Ö. and Önal, S.A. (2011)’ Fuzzy AHP Approach for Supplier Selection in a Washing
Machine Company, Expert Systems with Applications, Vol. 38, pp.9656-9664.
[19] Krishnendu, S., Shankar, R., Yadav, S.S.and Thakur, L.S. (2012) ‘Supplier Selection Using Fuzzy
AHP and Fuzzy Multi-Objective Linear Programming for Developing Low Carbon Supply Chain,
Expert Systems with Applications, Vol. 39, pp.8182-8192.
[20] Kulak, O., (2005) ‘A decision support system for fuzzy multi-attribute selection of material handling
equipments’, Expert Systems with Applications,Vol.29, No. 2, pp.310–319.
[21] Kulak, O., Satoglu, S., and Durmusoglu, M., (2004) ‘Multi-attribute material handling equipment
selection using information axiom’ , Proceedings of the 3rd international conference on axiomatic
design, ICAD2004, 21–24 June, Seoul. Brighton, MA: Axiomatic Design Solutions, Inc., 1–9.

45
[22] Lau Y. K. H. and Woo, S. O. (2008) ‘An agent-based dynamic routing strategy for automated
material handling systems’, International Journal of Computer Integrated Manufacturing, Vol.21, No.
3, pp.269 – 288.
[23] Liao and Chin (2011) ‘Fuzzy analytical hierarchy process and multi-segment goal programming
applied to new product segmented under price strategy’, Computers and Industrial Engineering, Vol.
61, No. 3, pp.831-841.
[24] Maniya, K.D. and Bhatt, M.G. (2011) ‘A multi-attribute selection of automated guided vehicle using
the AHP/M-GRA technique,’ International Journal of Production Research’, Vol. 49, No. 20, pp.
6107–6124.
[25] Mohaghar, A.Fatmi, M.R. Zarchi, M.K. and Omidian, A. (2012) ‘A Combined VİKOR-Fuzzy AHP
Approach to Marketing Strategy Selection, Business Management and Strategy, Vol.3, pp.13-27.
[26] Onut, S., Soner, K.S., and Mert, S. (2009) ‘Selecting the suitable material handling equipment in the
presence of vagueness’, International Journal of Advanced Manufacturing Technology, Vol.44. No.7–
8, pp.818–828.
[27] Raj, T., Shankar, R., Suhaib, M., Garg, S. and Singh, Y. (2008) ‘An AHP approach for selection of
advanced manufacturing system: a case study’, International Journal of Manufacturing Research, Vol.
3, No. 4, pp.471–498.
[28] Saaty T. L. (2008) ‘Decision making with the analytic hierarchy process’, International Journal of
Service Sciences, Vol. 1, No. 1, pp. 83-98.
[29] Saaty, T. L. (1994) ‘Fundamentals of Decision Making and Priority Theory with The Analytical
Hierarchy Process’, RWS Publications, Pittsburgh.
[30] Saaty, T.L. (2000) ‘Fundamentals of decision making and priority theory with the AHP’, Pittsburg,
PA: RWS Publications
[31] Sujono, S. and Lashkari, R.S. (2007) ‘A multi-objective model of operation allocation and material
handling system selection in FMS design’, International Journal of Production Economics, Vol. 105,
No. 1, pp.116-133.
[32] Sun, C.C. (2010) ‘A Performance Evaluation Model by Integrating Fuzzy AHP and Fuzzy TOPSİS
Methods’, Expert Systems with Applications, Vol. 37, pp.7745-7754.
[33] Tompkins J. A. (2010) ‘Facilities Planning, John Wiley and Sons,’ New York, NY, USA.
[34] Tuzkaya,G., Gulsun,B, Kahraman,C and Ozgen,D. (2010) ‘An integrated fuzzy multi-criteria decision
making methodology for material handling equipment selection problem and an application, Expert
Systems with Applications, Vol. 37, pp. 2853-2863.
[35] Vatansever, Kemal and Kazançoğlu, Yiğit (2014) ‘Integrated Usage of Fuzzy Multi Criteria Decision
Making Techniques for Machine Selection Problems and an Application’, International Journal of
Business and Social Science, Vol.5, No., 9 (1).
[36] Wabalickis, R.N. (1987) ‘Justification of FMS with the analytic hierarchy process’, Journal of
Manufacturing Systems’, Vol. 7, No. 3, pp.175–182.
AUTHORS
Surinder Kumar is a Research Scholar in the Department of Mechanical Engineering at the YMCA
University of Science and Technology, Faridabad, India. His areas of interest are advanced manufacturing
technology and flexible manufacturing systems.
Tilak Raj is working as a Professor in the Department of Mechanical Engineering at the YMCA University
of Science and Technology, Faridabad, India. He received his PhD from Jamia Millia Islamia, New Delhi.
He has been engaged with consultancy work also (in improving the manufacturing techniques in
industries). His area of expertise is manufacturing technology. His research papers are published /accepted
in Int. J. Flexible Manufacturing System, Int. J. Production Research, Int. J. Operational Research, Int.
J.Manufacturing Research and Int. J. Manufacturing Technology and Management.

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