Alvin Adi K (2509100056)
Rama P. Renspandy (2509100060)
Andi Reza R (2509100063)
Ikhsan Salman (2509100079)
Arif Z. W (2509100147)
(COMPUTERIZED RELATIVE ALLOCATION OF FACILITIES TECHNIQUE)
Computerized Relative Allocation of Facilities
Technique (CRAFT) is a tool that used to help improve
the existing layout of the facilities. The facility is
improved by swaping two or more departments to
help arrange the facility to an optimal floor plan.
When will CRAFT be used?
CRAFT is used when the number of departments is
enormous that the manual computation would be
nearly impossible to do.
CRAFT is basically used with process layout approach,
which also known as a functional layout that usually
used in job shops or a batch production facility.
What does the CRAFT do?
CRAFT do uses a pair wise exchange algorithm that may
not return the optimal result because the final solution
depends on the initial layout of the plant.
Rather than examine all the possible swaps, CRAFT
considers the swap of only adjacent department pair
or pairs that have the same area.
Steps of using CRAFT :
Basic step of CRAFT has been modified a number of
times, but we use COFAD (Tompkins and Reed, 1976) as
a reference, a four step algorithm, tackles the selection of
MHS and layout. These are the following steps:
1. Determines an initial layout.
2. Selects an MHS for the layout obtained in the first step
from a candidate list of equipment.
3. Calculates and revise the cost of each move based on
material handling equipment to each move. (These three
first step is repeated until a satisfactory solution obtained)
To get a good-quality final solution, the user must
provide different starting solution, evaluate the final solution
obtained by CRAFT for each of these and choose the best
Example of CRAFT :
This software (add-ins in
Ms. Excel) needs several
inputs to be defined, such as
layout information, facility
information, flow matrix, and
transportation cost. The
input (in Ms. Excel) will be
The next step will be generate the end layout, by clicking
the ‘define facility’ button.
By clicking the ‘define facility’ button, the software will
generate you the final solution layout :
Then, based on final
solution layout, the last part
is evaluated the final
solution for each of these
and choose the best one.
The output file generated
layout itself can be
classified into 3 parts:
This part will give the detail information, such as area required, area
defined, x-centroid, y-centroid, and the sequence. What method that
used, how the assumption of the layout, the measure of the department
distance also mentioned at the upper part.
Six buttons can be utilized to enhance the visual layout,
for instance, pressing the solve button will give the visual
layout how the end solution visual layout look like :
The last part explain how many iteration used and how
much do it cost to make the layout :
Advantages of CRAFT :
1. The fact that the calculation is done by computer –
sophisticated calculating machine – is clearly
advantages that save a lot both time and money in the
2. It gives us rooms to define the variable and constraints
that we have out here in the real world.
3. Flexibility can be seen as there are 6 buttons that can be
utilized to generate series of different end solution (in
Disadvantages of CRAFT :
2. Jobs time occured
Jobs do not flow through in an orderly fashion, therefore
backtracking occurs often. Idle time, more idle time may be
experienced while workers are waiting for more work to arrive
from different departments.
3. The (not) end result.
End result may need to be modified, because once CRAFT
has determined a solution it may need to be managed to
create a layout that fits in the plant.
4. Greedy algorithm.
It is the algorithm that always takes the best immediate
solution. In contrary, a job shop that flow through the system
is not always constant and causes fluctuations in the process.