1 2 . e l e c t r O t H e r a P y t H e O ry
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EN
WIRELESS PROFESSIONAL
12.3.5 Hydraulic model of excitation
It is possible to set up a hydraulic model that corresponds exactly to excitation. This model allows a better
understanding of excitation and may be used to represent the development of the local potential and the
threshold under the effect of currents with variable durations and shapes
Water flows from tank A towards tank B by means of pump P, the stimulator (current generator). The
flow of water corresponds to the intensity of the stimulation current and the water moved from A to B to
the quantity of electrical charges. The water level in tank B reaches a certain level representing the value
of the membrane potential
(Vo at rest and V local potential).
The stimulation threshold is given by a point D on float C. Stimulation occurs when level V in the tank B
reaches point D by submerging the float.
When pump P injects liquid from A to B therefore increasing level V, part of the liquid goes back to A
through tap K representing the excitation constant k. In the tank B, float C is linked to piston E that works
by means of the level of liquid in tank F. This is linked to B by tap L representing the accommodation
constant λ.