A flexible
hydrogel pressure distribution sensor has promising
application prospects. However, the current hydrogel pressure distribution
sensors are based on an array-type structure with complicated wires
and extremely low resolution, which greatly reduce the flexibility
of hydrogel and limit their applications. To overcome these limitations,
we proposed and designed a hydrogel pressure distribution sensor that
is able to obtain pressure distribution inside a whole piece of hydrogel.
This is specifically done by arranging electrodes only around the
hydrogel, which employs the strategy of electrical impedance tomography
(EIT). Meanwhile, PAAm/PAA-Fe3+ double-network hydrogels
were prepared as hydrogel pressure-sensitive substrates, and the feasibility
of PAAm/PAA-Fe3+ hydrogels as sensitive elements for hydrogel
pressure distribution sensors was confirmed through mechanical and
electrical tests. Furthermore, based on the hydrogel pressure distribution
sensor, a pressure distribution reconstruction model was obtained
with a machine learning method. To verify the feasibility of the hydrogel
pressure distribution sensor based on the EIT strategy, the hydrogel
sensor was applied with forces of known location and magnitude. Then,
the actual sensor acquisition data were reconstructed and compared
with the applied force.