I been spending my some time recently investigating
the rapidly expanding world of “motes,” a form
a wireless sensor that will undoubtedly revolutionize both
our lives and our supply chains.
A mote is a monitoring device that combines a small computer
(including an operating system and application software), one
or more sensors, and a radio for transmitting information.
Motes are often spoken of interchangeably with the term “wireless
sensor networks,” and aligned with the concept of “pervasive
computing.” RFID is in fact a type of mote, and active
tags especially are often lumped into this category. Defining
the relationships of motes and RFID from a sort of academic
sense is not easy, but it is clear that in many applications
RFID and motes will be working together to radically change
the way we monitor the environment.
The mote concept sprung in large part out of research at the
University of California at Berkeley in 1999, when Kris Pister (along with Randy Katz) published a paper about Smart Dust in the ACM conference on Mobile Communications (MobiCom). The mote concept (as we know it today) was invented transferred from Kris Pister's group by David Culler at the University of California, Berkeley. Culler's group created TinyOS and is now the lead maintainer of the operating system.
The basic idea is to enable sensor networks, capable of monitoring
a wide array of conditions and events (e.g., temperature, vibration,
movement, magnetism, light, even pictures and video), to operate
wirelessly – and to network with each other in a low
cost, flexible and robust fashion. Combine this with a path
towards ever smaller and smaller motes – sometimes termed “smart
dust,” the size of a piece of glitter or less – and
the cost to monitor things and the environment expand dramatically. Today, you can easily get a mote
that is the size of a quarter, but that may be attached to
a larger pack containing two AA batteries.
The easiest example: today in manufacturing plants, sensors
to measure machine vibration and other conditions are connected
via wire to the network, and are expensive to buy, install
and maintain. With motes, initial and lifetime cost of the
sensor goes way down, reducing costs for the same level of
sensing dramatically, and/or allowing companies to greatly
expand the number of measuring points.
Some motes can also operate in an “ad hoc’ network
fashion, meaning in part that they pass their data to each
other on the way to the ultimate “gateway,” rather
than to the gateway directly. This can reduce the battery power
needed (since the wireless distances for data are shorter),
enable robustness if a mote goes bad (the data finds another
path), and can allow very unusual applications with little “network
design” (think sprinkling motes over a battlefield to
monitor troop activity).
Eventually, motes will be in every building (e.g. monitor/control
energy use), our roads (smart highways), and our homes (security,
energy, lot’s more). But let’s turn to supply chain.
Motes are already being used in ocean containers to look for
evidence of tampering. (see
SCDigest Feb. 3, 2004).
They will have huge application in food, pharma, and other “cold
chain” industries to closely monitor temperature, humidity
and other factor. HP has tested motes with video capabilities
in combination with EPC tags in a distribution center in Memphis,
using image recognition software to ensure that goods are being
stored in the right place.
So, we may have situations where an RFID tag (EPC or not)
is directly included in the mote with one or more sensors.
Or, the mote may work in conjunction with standalone EPC tags
on various items. Reader networks may be motes, both generally
and perhaps for areas for which a temporary network is needed.
Indeed, it only though motes and related reader and application
networks that consumer goods companies will really benefit
We’ve only scratched the surface here. There are still
many issues, including battery life, standards, and applications
to make sense all that data. An example of the latter is a
company called SmartSignal (www.smartsignal.com),
which can process significant amounts of data coming from machine
sensors looking for signs of trouble – but they are one
of a few. You’ll see more on motes later from SCDigest.
Have you been looking at motes and the supply chain? Where
does the technology stand today, and how fast will it advance?
How do you think about motes and RFID?
Let us know your thoughts.