An actuator is the part of a machine that converts power or energy from electric current, hydraulic fluid, pneumatic pressure, or from other sources of power into motion.</p>
In other words, an actuator is responsible for moving a system. There are four main types of actuators, namely:
1. Electric Actuator
2. Hydraulic Actuator
3. Mechanical Actuator
4. Pneumatic Actuator
1. Electric Actuators:
They are powered by motors that convert electrical energy to motion. They are usually installed in engines, where they open and close different valves. They are considered to be one of the cleanest and readily available actuators because they are powered by electricity and not by oil.
2. Hydraulic Actuators:
They convert hydraulic power or energy in form of liquid to motion, which can be linear or rotary. They exert great motion but, unlike electric motors, they take more time to speed up and slow down. They can be operated manually or through a hydraulic pump.
3. Mechanical Actuators:
They convert mechanical motion into linear motion or into rotary motion. They convert into linear and rotary motion with the help of devices such as gears, chain, pulleys and rails.
4. Pneumatic Actuators:
They convert energy in form of compressed gas into linear or rotary motion. They are one the cleanest actuators, but they take a lot of space, produce a noise when in use, and they are difficult to transport after they have been installed.
The other types of actuators are solenoid, comb drive, screw jack, thermal bimorph, servomechanism, electroactive polymer, digital micro-mirror device, piezoelectric actuator, stepper motor, and shape-memory alloy.
Importance and Uses of Actuators
1. They convert energy into any kind of motion.
2. They are used in manufacturing or industrial applications.
3. Actuators help control the accuracy and positioning of beam in the laser positioning equipment used for laser surgery.
4. They are used in dental chairs to allow easy adjustment of the footrest, headrest, and chair height.
5. They are used in patient lifts to move patients within a hospital.
6. They are responsible for the buzzing sound you hear when your phone vibrates.
7. There are a lot of actuator in automobiles, performing a variety of functions.
8. They are responsible for the movement of arms, head, and legs of robots.
9. They are very important for making space vehicles.
10. Actuators are used to position solar panels in the day time and return them to resting position when the sun goes down.
11. They are used for making automated gates, TV screens, doors, and lifts.