## 15 February 2018

### Types of mechanical vibration

There are mainly three basic types of vibration according to the axis of body move :

1. Longitudinal vibration
2. Transverse vibration
3. Torsional vibration
Now we can check it out in detail below. Let us check out the different types of mechanical vibration here in this article. Before you start you can check some basic introduction of mechanical vibration

• Longitudinal vibration :
If the shaft is elongated and shortened so that the same moves up and down resulting in tensile and compressive stresses in the shaft, the vibrations are said to be longitudinal. The different particles of the body move parallel to the axis of the body.

• Transverse vibration :
When the shaft is bent alternately and tensile and compressive stresses due to bending result, the vibrations are said to be transverse. The particles of the body move approximately perpendicular to its axis.

• Torsional vibration :
When the shaft is twisted and untwisted alternately and torsional shear stresses are induced, the vibrations are known as torsional vibrations.

There are also some more vibrations that are following below :
1. Free and Forced vibration
2. Linear and non-linear vibration
3. Damped and Un-damped vibration
4. Deterministic and Random vibration
Now we can check it out in detail below :

• Free vibration :
After distributing the system, the external excitation is removed, then the system vibrates on its own. This type of vibration is known as free vibration.

Example - Simple pendulum

• Forced vibration
The vibration which is under the influence of external force is called forced vibration.

Example - Machine tools, electric bells

• Linear vibration :
In a system, if mass, spring and damper behave in a linear manner, the vibrations caused are known as linear in nature.

They are governed by linear differential equations.
They follow the law of superposition.

• Non-linear vibration :
If any of the basic components of a vibratory system behaves non-linearly that type of vibration is called non-linear in nature.

Linear vibration becomes non-linear for a very large amplitude of vibrations.
They do not follow the law of superposition.

• Damped and Un-damped vibration :
If the vibratory system has a damper and the motion of the system will be opposed by the damper also the energy of the system will be dissipated in friction is called damped vibration.

On the other hand, the system that has no damper is known as un-damped vibration.

• Deterministic and Random vibration :
In the vibratory system, the amount of external excitation is known in magnitude, it causes deterministic vibration is called deterministic vibration.

The non-deterministic vibration is known as random vibrations.