A Simplified Protocol for Energy Self-Sufficient
Sensors in an IEEE 802.15.4/ZigBee WSN
Lukasz Niestoruk
#1
, Johannes Schmid
#2
, Peter Boll*
3
,Wilhelm Stork
#4
, Klaus Mueller-Glaser
#5
#
Institute for Information Processing Technology, Karlsruhe Institute of Technology, Germany
*Elovis GmbH, Germany
{
1
lukasz.niestoruk,
2
johannes.schmid,
4
wilhelm.stork,
5
klaus.mueller-glaser}@kit.edu
3
boll@elovis.de
Abstract—For the application of wireless sensor network
technology in an energy self-sufficient condition monitoring
appliance, we propose a new hybrid network topology to combine
the advantages of the ZigBee standard with the need for lowest
power consumption when applying an energy harvesting solution
for a subset of the sensor nodes.
For a research project on a wireless condition monitoring
system, we developed a prototype implementation of a partly
energy self-sufficient wireless sensor network. We adapted the
ZigBee network protocols so that the energy consumption of
the self-sufficient nodes is reduced albeit a ZigBee conform
communication with the rest of the network is still ensured. In
this paper, the prototype system is presented and the problem
when applying a full ZigBee stack is stated. We propose to shift
parts of the network functionality from the end-devices to the
(mains- or battery powered) routers and show actual measure-
ment results and calculated values to indicate the improvements
of this adapted hybrid topology.
Index Terms—IEEE 802.15.4, industrial sensor network ap-
plications, sensor networks, ZigBee, energy saving, network
protocol, energy self-sufficient, wireless condition monitoring
I. INTRODUCTION
The application of wireless data transmission technologies
such as IEEE 802.15.4 / ZigBee in industrial environments
has been an important topic for the last few years [1], [2]
[3], [4], [5], [6] and holds a key position in the roadmap
of most machinery and plant construction companies. These
wireless technologies have a strong potential to reduce costs,
increase plant flexibility and security and to enable new
applications. On the other side new challenges arise when
applying wireless technologies in an industrial environment.
Different advantages, chances and requirements for wireless
technologies in industrial environments are summarized in [1],
[7] and [8].
In the last few years, several vendors have introduced
a broad range of wireless products to make use of these
possibilities and to amortize these chances. But so far there
are only very few implemented applications of wireless sensor
networks in industrial environments.
One application of wireless sensor network (WSN) tech-
nology in an industrial environment is in the field of con-
dition monitoring [9], [10], [11]. In the research project
”Self-sufficient Sensor System in a Self Organized Network
for Condition Monitoring in Industrial Environments” [12],
the applicability of an energy self-sufficient wireless sensor
network for a specific condition monitoring application is
developed and evaluated.
Fig. 1. System concept
Goal of the project is to develop an easily deployable
self-sufficient and self-organizing WSN to monitor the oil
temperature at multiple spots in different gearing devices in
a production plant and to communicate the data to a central
recording station (Fig. 1). With this data, the maintenance and
oil change intervals can be optimized.
For this purpose, energy self-sufficient wireless sensor nodes
(based on a thermogenerator) have to be integrated into the
oil drain plugs of the gearing devices. The thermogenerator
harvests energy from the temperature difference between the
hot oil inside the gearing and the cold surrounding air outside.
In this paper, the concept for a self-sufficient condi-
tion monitoring system, its implementation using the IEEE
802.15.4/ZigBee communication standard and the conse-
quences and necessary modifications of the standard, are
presented.
After the introduction (Section I), we present an overview
of the state of the art in the field of wireless sensor networks in
condition monitoring and applicable communication standards
for low power WSNs (Section II), and introduce our prototype
hardware (Section III). After that, we provide measurement
results of different ZigBee events and show why the system
cannot be implemented if keeping to the standard’s topology
and communication protocols (Section IV). Finally, we present
our approach to modify the IEEE 802.15.4/ZigBee standard’s
network topology and protocols. We introduce a new, stripped
down architecture (Section V) that provides interoperability
with a ZigBee backbone network while reducing the energy
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