PNEUMATICS

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Definition

Pneumatics is the use of pressurized gas to do a mechanical motion. Pneumatic power is used in industry, dentistry, construction, mining, and other areas.

Pneumatics works by taking the air around us and compressing or 'squishing' it into a smaller volume which increases it's pressure. That pressure is then used to apply a force to create a movement. To understand, think of those joke snakes in a can, when it is out of the can, it just lays there, but when pushed into the small space it wants to extend, so when the lid comes off, "pow".

Robotics Application

In robotics, pneumatics are usually used to do a game task. It may be to lift, push, pull or strike an object or lift the robot. Pneumatics can be a quick way to apply a force. Pneumatics can also be quite strong, which is why there are strict safety rule about the use of pneumatics within the robotics program.

A pneumatic system (see diagram) would usually have the following parts:

1. Air compressor: to squeeze the air
2. Air tank(s): to hold the compressed air until needed
3. Air line or hose: to carry the air between the other parts
4. Fittings: to connect the parts and split the line into multiple paths.
5. Pressure gauges: to show what pressure the stored air is at compared to normal atmospheric pressure
6. Regulators: a combination guage and valve part that adjusts the air pressure to a specified setting as it travels the system.
7. Valves: to control the movement of the air through the system, there can be various kinds, one that is always included is a special relief valve that removes the air from the system.
8. Actuators: This is the part that converts the air pressure into a mechanical force, such as an air cylinder or piston.

Pneumatic system Diagram (from usfirst.org, pneumatics manual)

Vocabulary

Actuator

A mechanical device that transfers the force of the compressed air into a mechanical motion. The most common is an air cylinder or piston. (double and single motion air cylinder images from wikipedia.org)

Air compressor

a mechanical device that increases the pressure of a gas by reducing its volume. Compressors are similar to pumps: both increase the pressure on a gas or fluid and both can transport it through a pipe. There are many types of compressors see Gas Compressor on Wikipedia for more information.

Force

That which causes an object to move. Often thought of as pushes or pulls.

Pneumatic or air cylinders

The expansion of air into a chamber pushes a piston attached to a rod which is connected to an object to be moved. See Pneumatic Cylinder on Wikipedia for more information.

Pressure

Pressure is the amount of force acting on a unit area. Pressure can be thought simply as 'pushing'.

Regulator

A special type of valve that uses a guage to set the airflow to a specific amount of pressure.

Valve

A device that regulates the flow of air by opening, closing, or partially obstructing various passageways. Valves can be moved by hand or triggered electrically. Valves can be used to switch the flow of air between different pathways, rather like a traffic light determines which road goes and which stops.

Volume

How much three-dimensional space an object occupies, often thought of as the size of an object.

Activities

If you wish to experiment with pneumatics and air pressure you can download these instruction sheets: