Fluidic Logic

There are opportunities for both new applications and knowledge to be derived from microfluidic investigations. The development of fluidic logic elements with hydraulic diameters in the 1-50 /i-m range is just beginning. 

Field-effect flow control Flow field-effect transistor Fluidic amphflcation and oscillation Fluidic logic... 

A logic circuit can be formed in a microfluidic chip by incorporating appropriate resistances and/or valves into the flow paths [1]. The various logical functionalities that can be integrated into a chip are OR, AND, NOR, NAND, conversion, and inversion. Fluidic logic can be designed to control the flow and/or mixing of droplets in a microchip. 

Flow field-effect transistor Field-effect flow control Fluerics Fluidic logic Fluidic amplification and oscillation... 

Fig. 1.3. An instrument system for GC-MIF including a fluidic logic interface. (Reproduced by permission, from S.A. Estes, PC. Uden and R.M. Barnes, Anal. Chem., 1981, 53, 1336 copyright 1981, American Chemical Society.)... 

Fluidics for Ordnance. Fluidics is the general field of fluid devices and systems with their associated peripheral equipment used to perform sensing, logic, amplification and control functions. Fluerics is that area within the field of fluidics in which fluid components... 

A fluidic amplifier controls the pressure and the flow rate in a microchip through the interaction of multiple fluid streams or jets. Fluidic amplifiers can be used for both analog (proportional) and digital (bistable) control. They can also be used to perform various Boolean functions in a microfluidic chip for the purpose of control logic. 

The basic operating principle of a bubble logic gate [3] is shown in Fig. 1. This microfluidic circuit consists of two input channels (A and B) and two output channels (Z and T). Channel X is shghtly wider than channel Y, i.e., channel X has a lower fluidic resistance than T. Hence, if a bubble reaches the junction by way of input channel A or B, then it will always take the output channel X owing to the lower fluidic resistance. But if two bubbles arrive simultaneously from input channels A and B, then the first bubble will take the output channel X. This first bubble increases the fluidic resistance of channel X and causes the other bubble to flow through channel Y. For detailed information on other microfluidic logic circuits, readers are advised to consult [3]. 

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