What are the sensor types of vibration&speed? and what is proximity sensor?

Vibration sensor based on1)fixed pt sendor2)variable sensor fixed sensor -by manual scale fixed near to machine valiable sensor-1)seismic transdusar2)clectromechanical tranducer3)capacitive rtnasdusor4)proximity type5)photodiode type proximity type -it is eddy current type .when we are giving supply -24 v.sensor develop Rf field.in machine eddy current develop ,due to current loss of power in Rf field so we get in o/t less voltage depend on gap voltage 

There are three type of vibration sensor use,axial redial and keyphasor.axial use for thurst movement,redial use to measure the rotor is in orbit,keyphasor is use to measure the speed,u can say rpm....thats all every kind of sensor have different measurement procedure...if any one need help ask free i will explain from field to VMS pannel

Vibration sensors are (Displacement type, Velocity type and acceleration type )

One of the displacement type is the proximity sensor which depends on the gap voltage between the probe and the target for which the vibration is measured.

Both velocity and acceleration types are seismic types where both measure an actual vibration so installed for example on a machine casing.