ССЫЛКА НА РАБОТУ ВНИЗУ.

An actuator is a mechanism that is responsible for launching motion in other devices. Consequently, it needs a source of energy. Actuators can be pneumatical, electrical, hydraulic, etc. They turn the given energy into mechanical motion. There also different kinds of motion, for example rotating, oscillatory and linear. The motion we analyze is called linear for producing movement along a straight line. It is used in various fields, from medical equipment to IT technologies.

Types of actuators in robotics

Electric
It is equipped with an electrical motor, which generates power. Due to the produced power, the linear actuator for robotics can convert a rotary motion into the linear. The electrical actuator is environmentally friendly because it doesn’t need any fluids to work. These devices are mainly spread in automatization mechanisms, such as DPS or cruise control. However, the price of this device can be higher than the average on the market.

Hydraulic
Hydraulic actuators operate on oil. Consequently, it is more harmful to the environment. It is equipped with the cylinder system, which allows producing different kinds of motion, for example linear, rotary, oscillatory, etc. The key point in the working process plays a piston. It provides a pressure needed for quick oil movement. The valve helps to give this flow the right direction.
The mechanism itself is very simple and old as well. So now it is mainly used in technologies where great power is required.

Pneumatic
Pneumatic actuators have a lot in common with the hydraulic ones. They are equipped with the same details, have the same working mechanism and old history. The difference is that a pneumatic actuator doesn’t have a motor, so the risks of an explosion are absent. Instead, it is powered by an electrical compressor. IT also doesn’t require oil or other harmful fluids. Pneumatic actuators work on the compressed air.
This device can produce a lot of energy, so it is especially useful when starting or turning off an engine.

5 linear actuators for a robotic arm to use

Scotch Yoke
This actuator helps to turn rotational motion into linear. This is how it works:

Solenoids
A solenoid consists of a steel plunger and an electric coil. When the electrical energy comes out, the plunger can be either pushed or pulled. This mechanism is mainly used in security devices, like door and car locks, bells, etc.

Pneumatic cylinders
This kind of robotics linear actuator is environmentally friendly because it works on renewable resources. Pneumatic cylinders are very strong and effective, so they can launch a very powerful motion. The size of every cylinder can vary, so you can choose the one that perfectly suits your robot. The motion is created by compressed air. It is cheap and not harmful for the environment.

Threaded rots
For creating a powerful linear actuator you will need a battery operated drill, a threaded rod, and matching nuts. To make a less complicated mechanism you should use cylindrical glue, modified servo and a slide potentiometer. A stepper motor is an important detail, which improves the actuator’s precision.

Pneumatic muscles
The name of this actuator is completely justified because the mechanism of its work reminds the way human muscles operate. The device consists of a skinny balloon and the braided tube. The balloons cannot expand more than when they are inflated. They only expand radially, creating a similar to human muscle mechanism.

Reasons to use in robotics

As it was said primarily, actuators are responsible for starting a motion. Except this, actuators control actions and movements making them safe and effective. This is a thing that is able to replace human power by the electric, hydraulic or pneumatic power. Robots with linear actuators are mostly not harmful to the environment and can use small amounts of renewable resources to produce a lot of energy. What is more, an actuator can be adapted to the conditions. For example, if it is a complicated security system, you should use an appropriate device with wide functionality. And when it is a simple robot, you can use a threaded rod.
Overall, it is up to you to choose the right actuator. Only you know the characteristics of your robot. You also should consider the price, the functionality and the harmfulness to the environment of the actuator technologies for robotics.
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