Non-Acoustic Sensors 18.7 AUV-Chemistry Sensors – Horizons 435
Part B | 18.7
fish egg sampling by obtaining continuous, accurate information on fish egg abundance in the area of interest.
REFLICS images the dynamic flow with a progressivescan area camera and a synchronized strobe that provides backlighting. The strobe illumination allows the
camera to acquire a sharp (no motion blur) image of the
flow. Digitization and processing occur onboard using
an image processing computer. REFLICS is capable of
working as an integrated system built up with a number of modules, frequently a CTD, working together to
achieve the objective of imaging, detecting, and classifying. REFLICS is also multi-platform capable and
has been installed on AUVs. REFLICS is proving to
be a cost-effective tool for oceanographers and marine
ecologists who need high-resolution real-time data on
fish egg distribution and abundance. REFLICS can be
improved in several ways, such as integrating a classifier, to be more robust.
18.6 AUV-Based Physical Sensors – Horizons
Historically, physical sensor technology has matured at
a faster pace than either chemical or biological sensor
technologies. A large industrial base exists for the manufacture of temperature, pressure, and physical property
sensors, and consequently there are more examples
of these types of sensors on AUVs. However, current
AUV-based physical sensor technology does not provide 3-D parametric physical information for water,
sediment, and groundwater over spatial scales ranging from the micro to kilometer scale volumes. One
particular topic in need of new sensors is fluid transport and fluid velocity for better characterization and
understanding of the phenomenon within the associated fields of research. Specifically, there is a need for
improved 1-D (one-dimensional) and 3-D flow field information in water and sediments. Additionally, there
is also a need to improve the capability of AUV sensors to provide the proper orientation of the sensor
in the environment; micro-turbulence measurements
are an example of the need for further advancement
in this area. Current developments in low power optical systems within the ultra-violet (UV) spectrum
for particle detection and characterization are the type
of technologies that may be an area of opportunity
for the import of innovation in AUV oceanographic
research. Discrimination of particles and nanoparticles, including the discrimination of non-biological
and biological composition with particle size distribution and shape sensors, in particularly with near
real-time response is an example of what is further
expected to emerge in AUV sensors systems over
time.
18.7 AUV-Chemistry Sensors – Horizons
The categorical space of chemistry is characterized by
high level segmentation into classes of compounds and
is further fragmented into a vast repository of individual
compounds which elude detection by specific chemical sensors. Thus, unlike the physical sensor space, the
chemical sensor space is highly fragmented and requires
many different instrument configurations to access the
variety of challenges associated with the field. A major
factor in the lag of chemical sensor maturation relative
to physical sensors is a continual issue. Consequently,
there will be a continual call from the ocean research
community to develop AUV-based chemical sensors for
a wide range of compounds in the chemical space for
organic, inorganic and biochemical samples within all
environmental media, i. e., atmospheric aerosols, sediments and sub-surface waters in and around fresh and
marine water systems. To date, there are few sensors that
are capable enough to measure multiple chemicals at
high acquisition rates, with suitable precision and sensitivity. There is a current need for sensors that can directly detect organic compounds of varying molecular
mass along with the structural context, such as lattice
cages. Small molecules include methane, halogenated
hydrocarbons, and toxins. CO 2 sensors, either optical
or chemical, and mass spectrometry are an example
of sensing systems that have garnered substantial attention recently and have been placed on AUVs. Sensors having multi-element and/or chemical speciation
capability at similar spatial and temporal resolutions
will be highly desirable to elucidate environmental processes in 3-D. Multi-sensor packages for simultaneous
physical and chemical parameters are essential to future
AUV oceanographic research. It is reasonable to believe
miniaturization will occur over time with widespread
use driving investment from manufacturers. Sensors that
can serve as chemical proxies for biological processes
are also expected to emerge over time and to help the
adoption rate of chem sensors on AUVs.
Part B | 18.7
fish egg sampling by obtaining continuous, accurate information on fish egg abundance in the area of interest.
REFLICS images the dynamic flow with a progressivescan area camera and a synchronized strobe that provides backlighting. The strobe illumination allows the
camera to acquire a sharp (no motion blur) image of the
flow. Digitization and processing occur onboard using
an image processing computer. REFLICS is capable of
working as an integrated system built up with a number of modules, frequently a CTD, working together to
achieve the objective of imaging, detecting, and classifying. REFLICS is also multi-platform capable and
has been installed on AUVs. REFLICS is proving to
be a cost-effective tool for oceanographers and marine
ecologists who need high-resolution real-time data on
fish egg distribution and abundance. REFLICS can be
improved in several ways, such as integrating a classifier, to be more robust.
18.6 AUV-Based Physical Sensors – Horizons
Historically, physical sensor technology has matured at
a faster pace than either chemical or biological sensor
technologies. A large industrial base exists for the manufacture of temperature, pressure, and physical property
sensors, and consequently there are more examples
of these types of sensors on AUVs. However, current
AUV-based physical sensor technology does not provide 3-D parametric physical information for water,
sediment, and groundwater over spatial scales ranging from the micro to kilometer scale volumes. One
particular topic in need of new sensors is fluid transport and fluid velocity for better characterization and
understanding of the phenomenon within the associated fields of research. Specifically, there is a need for
improved 1-D (one-dimensional) and 3-D flow field information in water and sediments. Additionally, there
is also a need to improve the capability of AUV sensors to provide the proper orientation of the sensor
in the environment; micro-turbulence measurements
are an example of the need for further advancement
in this area. Current developments in low power optical systems within the ultra-violet (UV) spectrum
for particle detection and characterization are the type
of technologies that may be an area of opportunity
for the import of innovation in AUV oceanographic
research. Discrimination of particles and nanoparticles, including the discrimination of non-biological
and biological composition with particle size distribution and shape sensors, in particularly with near
real-time response is an example of what is further
expected to emerge in AUV sensors systems over
time.
18.7 AUV-Chemistry Sensors – Horizons
The categorical space of chemistry is characterized by
high level segmentation into classes of compounds and
is further fragmented into a vast repository of individual
compounds which elude detection by specific chemical sensors. Thus, unlike the physical sensor space, the
chemical sensor space is highly fragmented and requires
many different instrument configurations to access the
variety of challenges associated with the field. A major
factor in the lag of chemical sensor maturation relative
to physical sensors is a continual issue. Consequently,
there will be a continual call from the ocean research
community to develop AUV-based chemical sensors for
a wide range of compounds in the chemical space for
organic, inorganic and biochemical samples within all
environmental media, i. e., atmospheric aerosols, sediments and sub-surface waters in and around fresh and
marine water systems. To date, there are few sensors that
are capable enough to measure multiple chemicals at
high acquisition rates, with suitable precision and sensitivity. There is a current need for sensors that can directly detect organic compounds of varying molecular
mass along with the structural context, such as lattice
cages. Small molecules include methane, halogenated
hydrocarbons, and toxins. CO 2 sensors, either optical
or chemical, and mass spectrometry are an example
of sensing systems that have garnered substantial attention recently and have been placed on AUVs. Sensors having multi-element and/or chemical speciation
capability at similar spatial and temporal resolutions
will be highly desirable to elucidate environmental processes in 3-D. Multi-sensor packages for simultaneous
physical and chemical parameters are essential to future
AUV oceanographic research. It is reasonable to believe
miniaturization will occur over time with widespread
use driving investment from manufacturers. Sensors that
can serve as chemical proxies for biological processes
are also expected to emerge over time and to help the
adoption rate of chem sensors on AUVs.