S.N.A.K.E.: A Dynamically Reconfigurable Artificial Sensate Skin ...

2.1.2 Ultra-dense Sensor Arrays
This second category of Artificial Sensate Skins differs from the previous one because of
their ultra-high sensor density. The other main difference is that these are also never
implemented as sensor networks but rather as sensor matrices. This means that each sensor
must be individually routed to a central processing unit. There are numerous works that
have developed high-density sensing arrays for their use as Artificial Skins some of which
are presented in the following list:
Takao Someya in [62] presents a large-area flexible sensor matrix with organic field
effect transistors (fig. 2-5(a)).
M. Sergio describes a textile-based capacitive sensor array that can be used as sensitive
skin[44] (fig. 2-5(b)).
Yong Xu, reports an IC-integrated flexible sensor skin that can sense shear stresses
for a possible aerospace application[74] (fig. 2-5(c)).
Papakostas talks about a large-area printable force sensor for smart skin applications
based on a piezoresistive effect[49] (fig. 2-5(d)).
Engel and others[11] talk about a multi-modal flexible skin fabricated with polymer
micro-machining methods (fig. 2-5(e)).
Darren Leigh presents DiamondTouch, a technology to create table-top input devices
based on capacitive sensing (fig. 2-5(f)).
The problem with these approaches though is that as sensor density increases, so does the
bandwidth required to retrieve information from the sensors. Moreover, a central processing
unit is forcefully required because the sensors can’t do anything by themselves. In spite
of this, these devices are currently the ones that have the greatest physical and functional
resemblance to our skin.
It is also necessary to say that there are several other projects with similar characteristics,
however, the previous list only presents a few as a way to exemplify them.
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