Yarn, detection system, fiber sheet, connector, detection device, and liquid type estimation method

1. A detection system, comprising:

a fiber sheet; and

a detection device,

wherein the fiber sheet comprises:

a fiber sheet main body formed of an insulating material; and

a sensor fiber including at least two conductive bodies that are combined such that they do not come in contact with each other,

wherein the sensor fiber comprises:

a first conductive yarn of the at least two conductive bodies having conductivity;

an insulating section covering the first conductive yarn and formed of an insulating material having absorbency; and

a second conductive yarn of the at least two conductive bodies having conductivity and disposed on an outer circumferential side of the insulating section,

wherein the detection device comprises:

an alternating current signal output unit configured to input an alternating current signal between the at least two conductive bodies formed on the fiber sheet;

a frequency characteristics acquisition unit configured to acquire frequency characteristics between the conductive bodies when the alternating current signal output unit inputs an alternating current signal between the conductive bodies; and

a detection signal output unit configured to output a detection signal when both of the following conditions are met, that is, when the alternating current signal output unit inputs a plurality of alternating current signals having different frequencies between the conductive bodies and the frequency characteristics acquired by the frequency characteristics acquisition unit show a predetermined difference according to a difference in frequency of the alternating current signal from the alternating current signal output unit, and when the alternating current signal output unit inputs the alternating current signals having the same frequency between the conductive bodies and the frequency characteristics obtained by the frequency characteristics acquisition unit at different times show a predetermined variation according to elapse of time,

wherein the alternating current signal output unit inputs at least three alternating current signals having different frequencies between a plurality of conductive bodies formed on the fiber sheet,

wherein the frequency characteristics acquisition unit acquires a value of impedance measured between the conductive bodies with each of the alternating current signals input by the alternating current signal output unit, and

wherein the detection signal output unit determines whether the frequency characteristics which is acquired by the frequency characteristics acquisition unit when the alternating current signal output unit input a plurality of alternating current signal having different frequencies between the conductive bodies shows a predetermined difference according to a difference in frequency of the alternating current signal from the alternating current signal output unit by obtaining a Cole-Cole trajectory that approximates impedance measurement values acquired by the frequency characteristics acquisition unit at a portion of an arc; obtaining a value of a circuit parameter in a predetermined equivalent circuit model simulating an impedance of a liquid having a membrane on the basis of the Cole-Cole trajectory and estimating a type of the liquid on the basis of the obtained value of the circuit parameter.

2. A detection device, comprising:

an alternating current signal output unit configured to input an alternating current signal between a plurality of conductive bodies formed on a fiber sheet;

a frequency characteristics acquisition unit configured to acquire frequency characteristics between the conductive bodies when the alternating current signal output unit inputs an alternating current signal between the conductive bodies, and

a detection signal output unit configured to output a detection signal when both of the following conditions are met, that is, when the alternating current signal output unit inputs a plurality of alternating current signals having different frequencies between the conductive bodies and the frequency characteristics acquired by the frequency characteristics acquisition unit show a predetermined difference according to a difference in frequency of the alternating current signal from the alternating current signal output unit, and when the alternating current signal output unit inputs the alternating current signals having the same frequency between the conductive bodies and the frequency characteristics acquired by the frequency characteristics acquisition unit at different times show a predetermined variation according to elapse of time,

wherein the alternating current signal output unit inputs at least three alternating current signals having different frequencies between a plurality of conductive bodies formed on the fiber sheet,

wherein the frequency characteristics acquisition unit acquires a value of impedance measured between the conductive bodies with each of the alternating current signals input by the alternating current signal output unit, and

wherein the detection signal output unit determines whether the frequency characteristics which is acquired by the frequency characteristics acquisition unit when the alternating current signal output unit input a plurality of alternating current signal having different frequencies between the conductive bodies shows a predetermined difference according to a difference in frequency of the alternating current signal from the alternating current signal output unit by obtaining a Cole-Cole trajectory that approximates impedance measurement values acquired by the frequency characteristics acquisition unit at a portion of an arc; obtaining a value of a circuit parameter in a predetermined equivalent circuit model simulating an impedance of a liquid having a membrane on the basis of the Cole-Cole trajectory and estimating a type of the liquid on the basis of the obtained value of the circuit parameter.

3. A liquid or gas type estimation method, comprising:

an alternating current signal inputting step of inputting at least three alternating current signals having different frequencies between a plurality of conductive bodies formed on a fiber sheet;

an impedance measurement value acquisition step of acquiring a value of impedance measured between the conductive bodies with each of the alternating current signals input in the alternating current signal inputting step;

a Cole-Cole trajectory acquisition step of obtaining a Cole-Cole trajectory that approximates impedance measurement values obtained in the impedance measurement value acquisition step at a portion of an arc;

a capacitance acquisition step of obtaining a value of a circuit parameter in a predetermined equivalent circuit model simulating an impedance of a liquid having a membrane on the basis of the Cole-Cole trajectory; and

a liquid type estimation step of estimating a type of the liquid on the basis of the obtained value of the circuit parameter,

wherein the alternating current signal inputting step is performed by an alternating current signal output unit,

wherein the impedance measurement value acquisition step is performed by a frequency characteristics acquisition unit configured to acquire frequency characteristics between the conductive bodies when the alternating current signal output unit inputs an alternating current signal between the conductive bodies,

wherein the Cole-Cole trajectory acquisition step, the capacitance acquisition step, and the liquid type estimation step are performed by a detection signal output unit,

wherein the detection signal output unit determines whether the frequency characteristics which is acquired by the frequency characteristics acquisition unit when the alternating current signal output unit input a plurality of alternating current signal having different frequencies between the conductive bodies shows a predetermined difference according to a difference in frequency of the alternating current signal from the alternating current signal output unit by performing the Cole-Cole trajectory acquisition step, the capacitance acquisition step, and the liquid type estimation step,

wherein the detection signal output unit is configured to output a detection signal when both of the following conditions are met, that is, when the alternating current signal output unit inputs a plurality of alternating current signals having different frequencies between the conductive bodies and the frequency characteristics acquired by the frequency characteristics acquisition unit show a predetermined difference according to a difference in frequency of the alternating current signal from the alternating current signal output unit, and when the alternating current signal output unit inputs the alternating current signals having the same frequency between the conductive bodies and the frequency characteristics obtained by the frequency characteristics acquisition unit at different times show a predetermined variation according to elapse of time.