This slide contains information about two type of accelerometer :- 1. Seismic Accelerometer 2 :- Displacement type accelerometer. it contains working and construction.

1. JAIPUR ENGINEERING COLLEGE AND
RESEARCH CENTRE
PRESENTATION ON
ACCELEROMETER
Submitted By:-
Ashesh Bansal
Arun Yadav
Submitted to:-
Mr. Ravi Yadav
DEPARTMENT OF MECHANICAL ENGINEERING

2. CONTENTS
 ACCELEROMETER
 PRINCIPLE
 HOW IT WORKS
 TYPES
 PIEZO-ELECTRIC TYPE
 SEISMIC TYPE
 APPLICATIONS
 REFERENCES

3. ACCELEROMETER
An accelerometer is an electro-
mechanical device that measures
proper acceleration forces. These
forces may be static like the constant
force of gravity pulling at your feet,
or they could be dynamic – caused by
moving and vibrating the
accelerometer.

4. The working principle of an
accelerometer is based on
PIEZO-ELECTRIC
EFFECT (due to
accelerative forces) and on
the DISPLACEMENT
SENSING (based on
displacement of mass).
PRINCIPLE

5. HOW IT WORKS
In most of the cases working of an
ACCELEROMETER is based on voltage
generation and its further
calculations which leads to the
determination of acceleration
where as some other involve the
measurement of displacement of
mass.

6. TYPES OF ACCELEROMETER
There are basically two types of
accelerometer frequently used for
measurement of acceleration:-
PIEZO ELECTRIC ACCELEROMETER
DISPLACEMENT SENSING OR SEISMIC TYPE
ACCELEROMETER

7. Piezo -Electric TYPE
It employs the piezo
electric effect of certain
materials to measure
dynamic changes. It
converts one form of
energy into another and
provide electrical signal
of measured amount.

8. Working Principle
The working principle of this is
based on “NEWTONS THIRD LAW” . The
force exerted on the material can be
observed in the change in the
electrostatic force or voltage
generated by the piezoelectric
material.

9.  Fastened on the base which act as a
spring and squeezes the mass against
crystal for acceleration determination.
 Leads to voltage generation and
fluctuation in voltage leads to
measurement of imposed acceleration.
 Sensor consist of
piezoelectric crystal
sand witched between
two electrodes with a
mass placed on it

10. ADVANTAGES
Rugged and
Inexpensive
High Impedance
High sensitivity
High frequency
response
DISADVANTAGES
Sensitive to
temperature
Hysteresis error
Less longevity
Decreased
efficiency with
time

11. SEISMIC ACCELEROMETER
In displacement sensing
accelerometer the displacement of a
mass resulting from an applied force is
measured and correlated to the
acceleration .Here a common spring –
mass-damper system which
accomplishes the task of acceleration
measurement through displacement.

12. Working Principle
The working principle
of this is based on
mass-spring-damper
combination and
similarly acceleration
calculation from
displacement.

13. The mass is supported by a spring
and connected to the housing frame
which is attached to a machine.
Relative mass movement is sensed
and indicated by an electrical
displacement transducer.
Correspondingly displacement and
velocity are measured and further
acceleration are measured.

14. Advantages
Easy Calculation
Simple and
reliable
Durable and
efficient
Disadvantages
Spring system
is not always
accurate
Fluctuation in
mass leads to
wrong
calculation.

15. Application of Accelerometer
Acceleration and vibration calculation
in vehicles
In industries for monitoring machines
Building and structural monitoring
Medical application and navigation
Transport

16. REFERENCES
 http://en.wikipedia.org/wiki/Piezoelectric_acc
elerometer
 http://en.wikipedia.org/wiki/Accelerometer
11/
 http://www.dimensionengineering.com/info/a
ccelerometers
 https://en.wikipedia.org/wiki/Accelerometer
 https://www.pcb.com/techsupport/tech_accel
.aspx