Abstract:
Ubiquitous availability of cellular network and cheap mobile
phones have made them promising sensing platforms for
various application domains including healthcare, environment,
and astronomy among others. However, existing mobile
phone platforms, including even smartphones, provide
limited in-built sensing capabilities and lack standard interfaces
to connect external sensors. In this paper, we propose
MELOS (Mobile Extension for LOw-energy Sensing) a lowcost
mobile phone extension that works virtually with all the
mobile phones, including low-cost phones since it interfaces
with the phone over standard audio port and Bluetooth.
The proposed platform augments mobile phones with additional
sensing capabilities with minimal overhead in terms
of energy consumption. MELOS provides capability to
switch on-board modules off as per application requirements
while keeping low power interface (audio) “always-on” (to
keep the connection) thus resulting in significantly small active
mode power consumption. Local storage capability on
board ensures that the data is transferred over high bandwidth,
high-power consuming Bluetooth interface in burst
mode resulting in low energy consumption per byte of data
transfer. Interface with a mobile phone ensures that the capabilities
of the MELOS platform can be exploited remotely
using the cellular connectivity. We prototype a sample application
to monitor energy consumption of several electrical
appliances and also demonstrate appliance control using a
relay based circuit incorporated in MELOS.
