More refined than simple on/off regulation of motion, proportional control of pneumatics is a cost-effective way to impart flexibility.
In these systems, a controller and fast-acting valve feed power to their connected cylinder to produce output linearly related to inputs — which include both a target value for a specific position, pressure, or force level, as well as the real-time measurement of actual progress toward that target.
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In addition, with proportional control, system output can be any interim value within a fixed range. For example, an air cylinder can be positioned anywhere between fully retracted and fully extended, and a tank’s pressure can be maintained anywhere between vacuum and full line pressure.