National
Institute of Industrial Engineering
Industrial
Engineering (PGDIE-42)
Review Paper
Summary on
Improvement
of the Reliability of Automatic Manufacture Systems by Using FTA Technique
Submitted to
Dr. KVSS
Narayan Rao
Article Details:
Title:
Improvement of the Reliability of Automatic Manufacture Systems by Using FTA Technique
Authors:
A.
Mahdi
Karbasian,
B.
Mahdi Rostami Mehr,
C.
Mojgan Agharajabi
Published in:
International Journal of Industrial Engineering &
Production Research,
Volume 23, Number 2
Page no (85-89)
June 2012
Abstract
In recent years, many manufacturing
industries for promoting their efficiency have tended to use the automatic
manufacturing systems. Expanding automatic systems and to increase their
complexity are representing the necessity of studying a proper functional
quality and using reliable equipment in such systems more than ever. In this
direction, the technique of fault tree analysis (FTA), along with using other
techniques such as failure mode and effect analysis (FMEA) reveals the
incorrect performance states (modes) in system in order to know these modes
exactly may prevent their occurrence and increase their function quality. In
this study, the approaches may increase the reliability of performance in an
industrial robot are studied by FTA technique as a case study to show
improvement in performance of equipments on automatic systems to reduce their
destruction (fault) during the work, and finally access to an automatic
manufacturing systems with high reliability.
Review
FBD Sketch to Four- Free Degree Robot
Determining the potential modes of
destruction is required to know and analyze the system perfectly. Here, there is the
system of cannibalization having four free- degree that has been designed in
order to move spares in the weight of maximum 500 gr [3].
In this robot have been used strong
steel arms and seven serves of dc motor with the moment about 30 kg and much
other electronic hardware.
FTA Plan
A Rooty conflict with maker
elements of undesirable modes in the phase of planning will cause to promote
the performance level in system. After recognition errors by FTA as a logical model
from up to down such as designing assistant, the system analyzing may be
considered, and possible destruction of system is evaluated. This analysis is
followed by using three procedures:
1- To draw the fault tree.
2- To determine the possibility of
fault
3- To know and estimating critical
sets resulted in the occurrence of top event.
Drawing Reliability Block Diagram of System
By surveying RBD, we compute total
reliability of system. Moreover, it is purposed to increase reliability of B1
and B2 components with respect to it is as series in system. But for computing
reliability of electronic components, Mil – HDBK – 217 standard is used, and
Mech Rel software is used for estimating reliability of mechanical pieces.
FMEA Plan to Present Proposed Measures
After finding potential fault
modes, to prioritize and knowing the causes, are the next step. For this, the
FMEA technique is used. This method is a systematic method of recognizing, and
prioritizing the fault in a system or product. It acts according to the
prevention law. One of the success elements in this technique is the time of
its performance and has been planned it, that would be a measure before event,
not an exercise after being revealed the difficulties.
Conclusion
By using the planned algorithm on
the base of FBD, FTA and FMEA tools, the below results can be achieved:
1) Recognizing the potential fault
roots in the first levels of planning.
2) Determining the cause of
potential faults
3) Prioritizing of the faults for
corrective actions
4) Performing of necessary actions
in order to reduce or delete the potential Failure
