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3.4.3 Final Concept and Design
In the final concept, five design concepts were generated. The explanations of
concepts are as follows:
Concept 1: there are two cushions that support the neck on the left side and the
right side. Both cushions are static.
Concept 2: there is only one neck support cushion. It is cylindrical in shape and
placed between head and shoulder. The cushion is static.
Concept 3: there are two cylindrical shaped side supports. Each side support is
rectangular in shape. Both side supports are placed on the left and the right side
of the head. Both airbags are parallel with each other. Both side supports can be
activated mechanically.
Concept 4: there are two rectangular shape side supports. The side supports are
placed on the left and the right side. Both side supports are activated at the same
time. Both side supports are powered by compressed air. The air flow to the
airbags is controlled by a directional valve. The microcontroller is ATmega and the
programming language is Processing.
Concept 5: there are two rectangular shape side supports. The side supports are
placed on the left and the right side of head. Each side support can be tilted and
activated differently in order to support the head effectively. Both side supports
are powered by compressed air. The air flow to the airbags is controlled by a
proportional valve. The air pressure is measured by the air pressure sensor. A
membrane potentiometer is used to detect the presence of passenger. The
microcontroller is ATmega. The programming languages are Processing and
Arduino.
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Concepts Evaluation
The evaluation of the five concepts was carried out by using the weighted
objective method Pugh, 1990. The five concepts were evaluated based on the
requirements as shown in Table 3.1. The evaluation of the five concepts is shown
in Table 3.3. Eight requirements have been set to evaluate the five concepts. Each
element was provided with relative weight e.g. performance 0.20, materials
0.10, size 0.10, reliable 0.20, weight 0.05, strength 0.15, safety 0.05 and
design 0.15. Two requirements, namely performance and reliable, were rated
with highest weight because the SnS
2
prototype should be functional and support the
passenger’s head as well as reliable during the validation experiment. During the
brainstorming session, each concept is rated with scores S using ten point scales.
Each point is multiplied by the objective weight to give relative values V. Each
value is summed up to get the total value for each concept. Subsequently, the
total values for each concept are compared and the highest values are selected.
Concept 5 as shown in Table 3.3 represented the highest values and was selected
as best concept. Concept 5 was selected because the concept is able to perform
with good functionality, cost effective material, adjustable size, reliable, light
weight prototyping material, good strength, safe and easy to maintain. The solid
modeling software, namely SolidWork, was used to visualize concept 5 in three
dimensions 3D as shown in Figure 3.19. The exploded view of the SnS
2
prototype
is shown in Figure 3.20.
Table 3.3 Weighted objective evaluation of SnS
2
prototype concepts.
Concept 1
Concept 2
Concept 3
Concept 4
Concept 5
No. Element
Weight S
V S
V S
V S
V S
V
1. Performance
0.20 2
0.40 2
0.40 5
1.00 5
1.00 6
1.20 2.
Materials 0.10
3 0.30
2 0.20
4 0.40
4 0.40
4 0.40
3. Size
0.10 5
0.50 2
0.20 5
0.50 6
0.60 6
0.60 4.
Reliable 0.20
5 1.00
3 0.60
3 0.60
5 1.00
5 1.00
5. Weight
0.05 4
0.20 5
0.25 3
0.15 3
0.15 4
0.20 6.
Strength 0.15
3 0.45
2 0.30
4 0.60
4 0.60
5 0.75
7. Safety
0.05 3
0.15 2
0.10 3
0.15 4
0.20 4
0.20 8.
Design 0.15
3 0.15
3 0.45
4 0.60
4 0.60
5 0.75
Total value
3.15 2.50
4.00 4.55
5.1
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Figure 3.19 The 3D isometric view of SnS
2
prototype.
Figure 3.20 The exploded view of SnS
2
prototype. Right
airbag Left
airbag
82 Based
on the evaluation results, the smart neck support system prototype was built.
Figure 3.21 shows the first SnS
2
prototype. Figure 3.22 shows the installation
of the final SnS
2
prototype to the economy class seat in the aircraft cabin
simulator. Figure 3.23 shows an overview of the final SnS
2
prototypes in the aircraft
cabin simulator for experimental purpose.
Figure 3.21 The first SnS
2
functional prototype.
Figure 3.22 The installation of the final SnS
2
functional prototype to the economy class
seat in the aircraft cabin simulator.
Right cushion
Left cushion
Neck cushion
Head cushion
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Figure 3.23 Three SNS
2
prototypes embedded in an economy class aircraft seat.
3.5 PROTOTYPE