Actuators and Their Uses
The use of actuators is a key component of mechanics. Automation refers to the starting and stopping of mechanical systems. An actuator is a device that causes mechanical equipment to start or stop using hydraulic fluid, electrical current or any other source of power. There are four main types of actuators, depending on which source of power they use to create motion, namely hydraulic, electric, pneumatic, or mechanical.
Hydraulic Actuators
These actuators convert hydraulic energy into mechanical work. These actuators can produce rotary, linear, or oscillatory motions. Hydraulic actuators are preferred because they can move heavy equipment and have high force capabilities. Hydraulic actuators can produce a large force, but they are still capable of providing mechanical stiffness. They can take some time to move as liquid cannot compress. An ordinary hydraulic actuator would be an empty cylinder with a piston inside. The piston can be made to move by pressing and depressurizing in order to create movement for a mechanical system Pneumatic Linear Actuator.
Electric Actuators
Because they are easy to interface with control systems that rely on electricity, these actuators are often found in many control systems. Also, unlike fluid and pneumatic energy, electrical energy can be easily obtained. These devices work by using electrical energy to create motion. Electrical energy is used to create torque by powering motors. Because electrical energy doesn't involve any tangible substance, it is much easier to clean up than hydraulic actuators that may leak. It is much easier to diagnose any issues with electric actuators. Electric actuators can be dangerous if they are not used properly. They also have a lower power-to-weight ratio than hydraulic actuators.
Pneumatic actuators
Pneumatic actuators convert compressed air pressure energy into motion that can be either rotary or linear. Pneumatic actuators are similar to hydraulic actuators. They also include a piston, cylinder and drive unit. There are also valves and ports. A diaphragm separates the piston from the pressurized gas in the cylinder that contains the piston. When air is compressed, it causes the diaphragm to move which then moves the piston connected to the valve stem. This creates motion. These actuators have the advantage that they don't need to be stored.
Motor actuators
These actuators convert rotary motion to linear motion by using pulleys, gears, chains, and other mechanical devices. Car jack is an example of a mechanical actuator. It converts rotary motion through a handle into linear through screw. To achieve a greater output, they require less input.









