Actuators:-
An actuator is a component of a machine that is responsible for moving or controlling a mechanism or system.
Mechanical Actuator:-
A mechanical actuator functions to execute movement by converting one kind of motion, such as rotary motion, into another kind, such as linear motion. An example is a rack and pinion.
The operation of mechanical actuators is based on combinations of structural components, such as gears and rails, or pulleys and chains.
Advantages:-
[1] Simple in construction
[2] Reliable
Disadvantages:-
[1] Slightly lower efficiency compare to other
[2] Frequent Maintenance required
Hydraulic Actuator
According to Pascal, when there is an increase in pressure at any point in a confined incompressible fluid, then there is an equal increase at every point in the container.
Hydraulic actuators are designed based on this principle (Pascal’s law).
Hydraulic actuators are majorly used for a systems which require very large force, but not very restrictive on positioning and accuracy.
Advantages of hydraulic actuators:
1. They can move moderate to heavy loads.
2. They are more efficient and deliver better performance than others.
3. Power to weight ratio of these actuators is high.
Disadvantages:-
[1] Leakage of fluid
[2] hydraulic fluid is flammable
[3] lags in the control of the system due to the transmission lines and oil viscosity changes from temperature