sis 
 QiuqinYue
1 
and Jielin Zhou
2
1
Chongqing College of Electronic Engineering, Chongqing, 401331, China  
2
Chongqing University, Chongqing,400044, China 
yqq622@163.com 
Keywords:  Engine Health Monitoring, Fault Diagnosis, Vibration Signal Analysis, Wireless Acceleration Sensor, Fast 
Fourier Transform. 
Abstract:  Aiming  at  research  on  engine  health  monitoring  and  fault  diagnosis  based  on  the  characteristics  of  the 
surface  vibration  signals  measured  from  the  engine,  a  measured  method  by  using  wireless  acceleration 
sensor is proposed in this paper. The basic characteristics of engine vibration  signal  taking the Chevrolet 
Epica 2HO automotive engine as an example was measured in this paper. The original measured data was 
pre-processed using the Fast Fourier Transform (FFT) to suppress abnormal interference of noise, and avoid 
the pseudo mode functions. Finally, the vibration signals of automotive engine are analyzed and the results 
show that the method is feasible and effective in feature extraction and condition evaluation of engine health 
monitoring and fault diagnosis.  
1  INTRODUCTION 
More and more importance of health monitoring and 
fault diagnosis has been realized, which is no longer 
a  supplementary  accessory  to  the  system,  but  a 
necessary and essential element to ensure reliability 
and  productivity  in  an  effective  and  cost-efficient 
way (Jin, 2014). Gasoline engines, as one of the key 
equipment in  a  variety of  applications,  have  always 
been  popular  as  the  subject  of  condition  health 
monitoring.  Engine  contains  abundant  fault 
messages.  Thus  the  gasoline  engine  health 
monitoring  and  fault  diagnosis  technique  based  on 
the  characters  of  engine  vibration  signal  is  adopted 
to  enhance  the  operation  reliability  and  reduce  the 
blindness of the maintenance work. Actually, engine 
is  a  complicated  mechanical  system  with  various 
vibration  excitations  and  different  corresponding 
excitation  mechanisms.  For  instance,  automotive 
engine  is  chosen  as  an  illustrative  case  study.  In 
normal condition,  the gas pressure and inertia force 
are  the  most  common  and  immediate  excitation 
sources  of  the  automotive  engine.  They  act  on  the 
automotive  engine  with  their  own  effect  rule  and 
frequency  and  cause  a  wide  variety  range  of 
vibration  signal.  Specifically,  the  gas  pressure  acts 
mainly on the cylinder head and the frequency band 
covers  from  tens  to  thousands  Hz;  but  the  inertia 
force acts on the cylinder block and manifest a slow 
frequency  harmonic  oscillations.  So  the  accurate 
extraction  of  vibration  signals  is  very  important  to 
the  engine  health  monitoring  and  fault  diagnosis 
(Chandroth,  1999;  Taglialatela,2013;  Gravalos, 
2013; Geng, 2003).  
Recently,  In  order  to  monitor  engine  health and 
further  diagnose  faults  in  gasoline  engines,  various 
successful methodologies have been developed. S. P. 
Mitchell Lebold et al intensively investigated several 
different methods to analyse faults based on injector 
signal,  vibration  signal,  and  speed  encoder  signal. 
Misfire  faults  have  been  successfully  identified 
using  time  domain,  frequency  domain  and  order 
domain  analysis  tools.  Signals  of  each  category  of 
every method were presented to show the difference 
between  normal  and  faulty  condition,  and  the 
quantization of the difference is later formulated. All 
the  approaches  had  the  ability  to identify  the  faulty 
cylinder  location  (Jin,  2014).  Mollazade  et  al. 
presented a fault diagnosis method for external gear 
hydraulic pumps based on a fuzzy inference system 
(FIS)
 
(2009). Sakthivel  et  al. used decision tree and 
other machine learning algorithms for fault detection 
of  mono-block  centrifugal  pump.  Ahmadi  and 
Mollazade investigated fault diagnosis of an electro-
pump  in  a  marine  ship  using  vibration  analysis 
(2010).  Muralidharan  and  Sugumaran  presented  a