1. A method of manufacturing a sensing element (1) for a non-invasive testing device (100),
the method comprising:
heating a substrate to a first predetermined temperature in presence of a carrier gas
in a furnace;
introducing hydrocarbons and catalysts into the furnace through the carrier gas and
maintaining the substrate at the first predetermined temperature for a first predefined time
to produce a carbon nanotube;
placing the carbon nanotube in a volatile solvent and adding additives to form a
carbon nanotube mixture;
stirring the carbon nanotube mixture for a second predefined time at a second
predetermined temperature and maintaining the stirred carbon nanotube mixture for a third
predefined time at a third predetermined temperature; and
filtering the carbon nanotube mixture to obtain the sensing element (1).
2. The method as claimed in claim 1, wherein the substrate is a silicon wafer.
3. The method as claimed in claim 1, comprising cleaning the substrate with a solution,
rinsing the substrate with deionized water and drying the rinsed substrate with a gas, before
subjecting the substrate in the furnace.
4. The method as claimed in claim 1, comprising cooling the substrate maintained in the
furnace to form the carbon nanotube before placing the carbon nanotube in the volatile
solvent.
5. A non-invasive testing device (100), comprising:
at least two covering layers (3);
a sensing element (1) disposed between the at least two covering layers (3), the
sensing element (1) configured to generate piezoresistive signals corresponding to the
pulses generated by a user; and
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one or more electrodes (2) extending from each side of the sensing element (1), the
one or more electrodes (2) are adapted to receive and transmit the piezoresistive signals
generated by the sensing element (1).
6. The non-invasive testing device (100) as claimed in claim 6, wherein the sensing element
(1) is a layer of multi walled carbon nanotube.
7. The non-invasive testing device (100) as claimed in claim 6, wherein the one or more
electrodes (2) are communicatively coupled to a computing unit (CU), the computing unit
(CU) is configured to receive the piezoresistive signals generated by the sensing element
(1) from the one or more electrodes (2).
8. The non-invasive testing device (100) as claimed in claim 6, wherein the at least two
covering layers (3) are made of a polymeric material.
9. The non-invasive testing device (100) as claimed in claim 6, wherein the one or more
electrodes (2) are made of an electrically conductive material.