Image Processing Reference
In-Depth Information
FIGURE .
Wireless vibration sensor.
•
EX certification:
: the environment on oil and gas rigs is hazardous. The sensor and
repeater nodes must be certified to operate in an EX Zone area, i.e., nodes will inter-
mittently be subjected to flammable material (oil or gas), and must therefore limit the
energy of any sparks and surface temperature.
•
Nonintrusive (easy to mount and retrofit):
: the sensor/repeater nodes must be easily
mounted on the motors. Some motors have mounting locations prepared while others
do not, and the mounting constructions also differ from case to case. he orientation of
the sensor element and location on the motor (preferably close to the bearing) matters
from a vibration analysis point of view, which can be in direct conflict with an optimal
antenna positioning. All of this must be taken into consideration for the physical design
of the sensor nodes.
•
Battery powered and a long battery life
: the requirement is that a sensor node should
haveatleastayearlifetimewithoutanybatterychange.
•
Duty cycle
: each sensor node should perform one vibration measurement per “two
weeks” and send it to the asset management system for analysis. his is a bit opposed to
the “typical” view of a WSN, which sends small amounts of data “fairly often” (minutes,
hours, or days).
•
Operating environment
: the temperature can vary from well below zero up to, or even
over,
○
C. In addition, the wireless communication solution must be able to cope with
the possible interfere caused by the many metal constructions found on an oil rig.
•
Security
: authenticity (making sure data comes from the correct sensor node) and
integrity (making sure no one has tampered with the data) is very important. herefore,
it is also important that we only allow authorized nodes to join the network.