How does an Accelerometer Work?

">as missile launch, weapon fire system, rocket
WHAT IS AN ACCELEROMETER?deployment etc. Many a times these accelerometers
An accelerometer is an instrument for measuringare used to protect fragile equipment during cargo
acceleration, detecting and measuring vibrations, or fortransportation, and report any strain that might cause a
measuring acceleration due to gravity (inclination).possible damage. Some companies have also
Accelerometers can be used to measure vibration onmanaged to develop a wireless 3-axis accelerometers
vehicles, machines, buildings, process control systemswhich are not only low in cost but are also shock
and safety installations. They can also be used todurable. This 3-axis accelerometer has sensors that
measure seismic activity, inclination, machine vibration,are used to protect mobiles and music players. Also
dynamic distance and speed with or without thethese sensors are used in some of the devices used
influence of gravity.for traffic navigation and control.
HOW DOES AN ACCELEROMETER WORK?PIEZOELECTRIC SENSOR
Used for calculating acceleration and measuringDepending upon the kind of work, the accelerometers
vibrations, the accelerometer is capable of detectingvary in the way they are prepared and how they
even the slightest movements, from the tilting of awork. Some accelerometers use piezoelectricity, these
building to smallest vibration caused by a musicalare man-made. In such accelerometers the
instrument. Inside the accelerometer sensor minuteacceleration is calculated based upon the charges
structures are present that produces electrical chargesderived from the microscopic crystalline structures
if the sensor experiences any movement.when they are accelerated due to motion.
Accelerometers need to be placed on the surface ofMEMS ACCELEROMETER
the object in order to determine the vibrations. It is notAnother kind works with the capacitance and the
capable of work in isolation or apart from the object itchanges initiated within it as a result of some
is required to assess, it must be firmly attached to theaccelerative force. This technology is used from
object in order to give precise readings.automotive industry to agriculture industry and from
KINDS OF ACCELEROMETERNASA to military researches and operations.
The two kinds of basic accelerometers are:STRAIN GAUGE
1. ANALOG ACCELEROMETERThis device is used to measure strain in an object,
At times Inputs and output readings also matterwhich is detected by a foil strain element. If the object,
especially when it comes to determining the kind ofto which the gauge is attached is some how
accelerometer that needs to be placed on a certaindeformed that creates electrical charges and is known
object. If the output is digital then a digitalas the gauge factor.
accelerometer must be placed and vice versa. TheACCELEROMETER IS USED IN:
main feature of this accelerometer is that the outputAUTOMOTIVE INDUSTRY
tends to change when there is even a slight change inDue to high demand and wide spread use of
the input.accelerometers in the automotive industry and new
The most common type of this accelerometer is usedhi-tech technology, these sensors are now light weight
in airbags of automobiles, to note the sudden drop inand are available at low cost and reduced prices.
the speed of the vehicle and to trigger the airbagMICROPHONES
release. Even laptops are now being equipped withMicrophones also carry accelerometers. That is how
accelerometers in order to protect the hard drivethey are able to detect the minute frequencies.
against any physical dangers, caused mainly due toROBOTICS
accidental drops.The forces that can cause vibrations which are
2. DIGITAL ACCELEROMETERdetected by the accelerometer can be static, dynamic
The digital accelerometer is more sophisticated thanor gravitational. Certain accelerometers are rated G. G
the analog. Here the amount of high voltage time isstands for Gravity. Such accelerometers are used
proportional to the acceleration. One of its majormostly in robotics. They are more sensitive to motion
advantages is that it is more stable and produces aand can be triggered at the slightest changes in
direct output signal. Accelerometers are now alsogravitational pulls.
used in aerospace and many military applications, such