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Chemical Technology • November/December 2016
shuttles creating the first environmental monitoring system
capable of taking measurements three dimensionally.
In the initial test deployment, the wireless mobile sensing
platforms traversed cables along three separate transects
of the forest understory. During the deployment, the shuttle
stopped at 1 m intervals along each transect for 30 s to
allow sensors to equilibrate and take the required measure-
ments. Each transect pass required 30 minutes and each
transect ran for 24 hours.
Advantages of a system based on
LabVIEW
By implementing the system using National Instruments
’
modular hardware and software, a flexible system was
developed with the additional communication and con-
figuration advantages of LabVIEW software. CompactRIO
was selected as the central measurement unit and the NI
Compact FieldPoint network interface with cFP-180x control-
lers was selected for distributed wireless measurements.
The NI Wireless Access Point (WAP-3701) was chosen to
transfer data between the distributed sensors, the towers,
and the canopy floor.
L
abVIEW was chosen to connect to these distributed
wireless measurement platforms and programme the em-
bedded CompactRIO processor. Using LabVIEW, measure-
ments to local researchers in different data formats can be
provided so that they can perform post-analysis. Because
of the flexibility of LabVIEW, researchers can configure
measurement types, select channels, and even add scaling
from a laptop connected to the system.
LabVIEW also provides advanced analysis tools for
real-time embedded processing to perform local mass flux
analysis and post-processing for remote researchers. In
addition, LabVIEW is equipped with an HMI, so real-time
measurements can be seen.
Future expansion
In conjunction with the system designers at CENS, it is
planned to expand the system by adding high towers ap-
proximately 45 m above the forest floor with canopy walk-
ways and to increase the total number of measurement
systems. Students from around the world can access the
canopy walkways to experience the unique atmosphere and
biodiversity of the rain forest canopy.
Additionally, remote data access will be delivered through
the Web to researchers and students who are not on-site.
Using a Web browser and the Web capabilities of LabVIEW,
researchers everywhere will be able to access and download
live and archived data for their own analysis.
“Because of the flexibility of
LabVIEW, we can configure
measurement types, select
channels, and even add scaling from a
laptop connected to the system.”
– Dr William Kaiser, UCLA
This diagram shows how researchers can collect measurements using the wireless
measurement systems connected between towers in the forest canopy.
The NIMS based on NI technology will help researchers take better measurements at
the La Selva Biological Station.
CONTROL AND INSTRUMENTATION
The NIMS measurement unit using CompactRIO and LabVIEW traverses on a cable
between towers at the La Selva Biological Station.