productivity is monitored only by the presence of
workers in the location and then by recording the
resulting interim products executed by supervisors.
While supervisors have difficulties to closely
monitoring the real performance of workers,
especially to differentiate between workers with
acceptable performance and under performance
during they are doing the activities. This will finally
make shipyard management difficult to estimate the
overall project performance and frequently will
affect the ship delivery time.
Further problems will arise if new approach in
salary system based on real performance of workers
is implemented in order to improve the overall
productivity and finally the profit of shipyards. This
new approach will require the real time monitoring
system as the basis of performance measurement
activities of workers. Many skills and competences
of workers involve in the process of shipbuilding
from fabrication, sub assembly, assembly and
erection. It was observed during the research that
every worker has typical gesture motion in doing
their activities. If such typical gesture motion of
workers can be identified and recognized by the
developed system, it will make possible to improve
significantly the overall shipyard productivity.
In this first phase of the research, an observation
was focused on the development of the real time
monitoring system to record, to identify and to
recognize of gesture motion of fabrication workers.
It was also identified that the most important part of
the system is censor location in the body of workers.
The censors must be located in the part of bodies
that moves dominantly to express typical motion
gesture. This has been executed by doing video
recording to the fabrication activities. Further this
was followed by simulating and captioning the
typical motion by using Microsoft Kinect and IPi
Motion Capture Studio Software.
An analysis using IPI Motion Capture Software
can then be executed to determine the dominant
parts of bodies that can show the typical gesture
motion of worker. It was identified that the position
or location of the body parts showing the most
significant movement for all activities performed by
fabrication workers was the Right Fore Arm to
record hand gesture motion using gyroscope and
Lower Spine to record linier movement of the body
using accelerometer.
A prototype of the developed system based on
wearable devices consisted of Arduino
microcontroller and two sensors accelerometer and
gyroscope has been explained clearly in the previous
paragraphs. This is then followed by trying the
system prototype to the workers in the laboratory in
order to evaluate the performance of the system.
During the system trial, various configuration of
fabrication activities of workers has been tried and
the resulting gesture motion of workers has been
recorded by two censors simultaneously. The
gyroscope censor records the gesture motions of
right hand of the worker and accelerometer censors
records the linear gesture motions of lower spines of
the worker. The two censors record the motions in
the three directions X, Y, Z.
A graph showing the gesture of worker motion
and its calculated MSE (Mean Squared Error) were
obtained from each work activity performed. The
application system will recognize the typical proper
work activities through the MSE values generated by
the recording data. If the MSE value on three each
axis X, Y, Z has a small value, the application
system will recognize as a proper work activity.
However, if the MSE value produced is large, the
system will state that it is improper work activity.
8 CONCLUSION
From the facts and discussion above, it can be
concluded as follows.
The dominant body part when fabrication
worker performs typical activities is right
forearm signing as hand gesture motion and
lower spin showing linier movement of body.
A prototype of proposed system developing a
combination of the IMU (Inertial Movement
Unit) system with the accelerometer and
gyroscope sensor modules and the Arduino
Uno microcontroller can be used to perform
motion capture and monitor the gesture motion.
A graph showing the gesture of worker motion
and its MSE (Mean Squared Error) were
obtained from each work activity performed.
Proper work activities can be recognized by the
MSE values generated by recorded motion
data. If the MSE value on three axis (X, Y, Z)
has a small value, then it will be recognized as
a proper work activity. On the other hand, if
the MSE value produced is large, the activity
will be recognized as improper work activity.
It was recognized the factors that influence the
recording data is because of noise data
generated by accuracy of censor readings.