Fluidics ( fluidic logic) is the use of fluidic devices for signal processing in automation technology. It is based on the principles of fluid mechanics and used pneumatic or hydraulic auxiliary power.

Flow Mechanical Components work with the help of liquid or compressible media such as air, water or hydraulic fluids. The proportion hydraulic control plays only a minor role. They are - combined to form integrated circuits - used both in analog and digital circuits.

Fluidic systems were developed in the 1960s and replaced in the 1970s by the microelectronics. So-called dynamic fluidic systems (see below) are currently used still for a few special tasks.


There are two types of fluidic systems:

  • Static fluidic systems in which movable parts (pistons, valves, slides or membranes ) are used
  • Dynamic fluidic systems in which no moving parts are present (dynamic, because they must be continuously supplied with compressed air).

Static fluid control systems


  • UNALOG ( universal low- analog and logic system)
  • DRELOBA binary control system
  • Useppa

Dynamic fluidic systems

Types of fluid mechanical switching elements:

  • Turbulence amplifier or Pneumistoren ( means essentially pneumatic transistors) as a pulse amplifier or as NOT gates
  • Wall beam elements (see Coandă effect) as a wall jet - flops ( flip-flops, that is, memory elements) and logic elements ( gates: OR / NOR, AND / NAND).


The channels of the fluidic circuit elements are usually etched or pressed into plastic.

Advantages and Disadvantages

Flow Mechanical switches are characterized by lack of wear, reliability and insensitivity to heat, ionizing radiation and vibration.

A disadvantage is the slowness ( relatively long switching, relatively low frequencies).


The fluidics has come inter alia, in the aerospace, military technology, industrial control, medical devices and also in the daily use of the application.


  • A. Böge: The technician manual. 11th edition. F. Vieweg & Sohn, Braunschweig and Wiesbaden, 1989, S.1517, in 1530.
  • Hans Ebert Homes and Siegfried Held User: Fluid technology from A to Z. United Fachverlage, Mainz 1995 ISBN 3-78-300286-9.
  • James W. Joyce: Fluidics. Basic components and applications. Maryland 1983. (PDF)

Further Reading

  • Gerhart Kriechbaum: Pneumatic control systems, Vieweg, 1997 ISBN 9783528140571.
  • Thomas Krist: hydraulics, pneumatics, fluidics - Pneulogik: formulas, data, concepts; for vocational training, study and practice. 4th edition Hoppenstedt, Darmstadt 1991.
  • Adolf W. rights: Fluid systems: fundamentals, devices, circuits. Springer, Berlin 1976.
  • Günter Ortmann: logic and Fluidic: a reference guide for terms, symbols, devices, and circuits of the control systems in general and the Fluidiktechnik and its peripheral areas. Ortmann, Hilden 1973.
  • Eduard Karg: fluidics: short and sweet. Elementary Introduction to the technology of pneumatic logic elements. Bird, Würzburg 1972.
  • László Helm et al. Introduction to the fluidics: pneumatic logic elements and systems. Oldenbourg, München 1971.