Part B | 18.2
424 Part B Autonomous Ocean Vehicles, Subsystems and Control
Table 18.1 Sensor space based on stimulus to identify existing sensor system types
Stimulus
Applications
Acoustic
Wave amplitude, phase, polarization, spectrum,
wave velocity
Biological
Bio-species (types, conc. states)
Chemical
Compositions (identity, conc. states)
Electric
Charge, current, potential, voltage, electric field
(amplitude, phase, polarization, spectrum),
conductivity, permittivity
Magnetic
Magnetic field (amplitude, phase, polarization,
spectrum), magnetic flux, permeability
Mechanical Positions (linear, angular), acceleration, stress,
pressure, strain, mass, density, speed of flow,
rate of mass transport shape, architecture, stiffness, viscosity, other
Radiation
Type, energy, intensity, other
Thermal
Temperature, flux, specific heat, thermal conductivity
Optical
Wave amplitude, phase, polarization, spectrum,
wave velocity, refractive index, emissivity, reflectivity
applications from the terrestrial and space fields has
greatly contributed to what is now considered part of
an oceanographer’s toolbox. For example, advanced
analytical chemical systems, microelectronics, computers, and satellites are now commonly included as
available ocean technologies. Innovations have and
will continue to be brought over from the medical,
military, and water treatment fields as they develop
aquatic and parameter measurement sensors. Grouping the current state of sensor technology within
the chemical, biological, and physical classes is adequate for a snapshot of the current state; however, in general, any of the sensors can be lumped
into either radiation, fields, or mass transfer-based
systems.
As a starting point, the treatment of non-acoustic
ocean sensor solutions using a function classification
scheme based on stimulus may be a reasonable starting point to categorize and organize existing sensors.
Table 18.1 provides a summary of the stimuli and the
composition of applications space. The generic sensor
space categorization by stimulus leads to more specific
non-acoustic sensor systems that most are familiar with,
for example, non-acoustic current/flow meters, optical
systems, thermistors, dissolved oxygen, plankton samplers, fluorometers, radiometers, magnetic current/flow
meters, seismometers, mass spectrometers, and laser
Raman spectrometers.
State-of-the-art non-acoustic sensor systems are
a summation of five areas: advanced analytical detectors, distributed computing, network technology, automation and power systems. All of these areas are
critical towards the advancement of more capable ocean
sensing and observatories. However, new analytical
functions are our focus and the basis for organizing
the non-acoustic sensors space. Consider, for example, the question as to what scale the sensor system
of interest needs to operate at. Spatial and temporal
elements of the environmental continuum versus the
spatial and temporal continuum of the sensor system
have to be contemplated when looking to derive appropriate sensor-AUV selections.
18.2 Classical Non-Acoustic Ocean Sensors
Acoustics have been a dominant technology in ocean
studies such as mapping and surveys. However, many
ocean spatial and temporal process phenomena require
other sensory modalities to properly access the space,
time, and composition. In the case of particle characterization for size, form, and temporal dynamics, acoustic
systems provide sensing abilities for longer temporal
and spatial scales. In contrast, non-acoustic ocean optical systems provide similar time–space coverage but
also extend to both longer and shorter characterization
time scales. Depending on the platform selected for sensor deployment, optical systems can also extend into
different spatial scales (Fig. 18.1).
Traditional non-acoustic sensors have matured primarily in the physical sensing area. The measurement
of temperature is a great historical example of this maturity process, and it is still prevalent today. Examples
of temperature sensing include the thermistor, thermistor string, and electronic reversing temperature sensor.
Temperature measurement systems of all types, both
general and high precision, are considered mature technologies.
Depth or water column pressure is another common measurement. Examples of pressure measurement
systems include quartz pressure sensors, solid state
diaphragms designed as submersible pressure transducers, such as piezoresistive sensors with an isolated
stainless steel diaphragm in a stainless steel or titanium package. Their uses include wave and tide gauges,
tsunami detection, ocean current surveys, and seabed
subsidence.
Salinity is widely perceived as a fundamental variable in the regulation of natural marine systems. It
is a key parameter in determining seawater physical
424 Part B Autonomous Ocean Vehicles, Subsystems and Control
Table 18.1 Sensor space based on stimulus to identify existing sensor system types
Stimulus
Applications
Acoustic
Wave amplitude, phase, polarization, spectrum,
wave velocity
Biological
Bio-species (types, conc. states)
Chemical
Compositions (identity, conc. states)
Electric
Charge, current, potential, voltage, electric field
(amplitude, phase, polarization, spectrum),
conductivity, permittivity
Magnetic
Magnetic field (amplitude, phase, polarization,
spectrum), magnetic flux, permeability
Mechanical Positions (linear, angular), acceleration, stress,
pressure, strain, mass, density, speed of flow,
rate of mass transport shape, architecture, stiffness, viscosity, other
Radiation
Type, energy, intensity, other
Thermal
Temperature, flux, specific heat, thermal conductivity
Optical
Wave amplitude, phase, polarization, spectrum,
wave velocity, refractive index, emissivity, reflectivity
applications from the terrestrial and space fields has
greatly contributed to what is now considered part of
an oceanographer’s toolbox. For example, advanced
analytical chemical systems, microelectronics, computers, and satellites are now commonly included as
available ocean technologies. Innovations have and
will continue to be brought over from the medical,
military, and water treatment fields as they develop
aquatic and parameter measurement sensors. Grouping the current state of sensor technology within
the chemical, biological, and physical classes is adequate for a snapshot of the current state; however, in general, any of the sensors can be lumped
into either radiation, fields, or mass transfer-based
systems.
As a starting point, the treatment of non-acoustic
ocean sensor solutions using a function classification
scheme based on stimulus may be a reasonable starting point to categorize and organize existing sensors.
Table 18.1 provides a summary of the stimuli and the
composition of applications space. The generic sensor
space categorization by stimulus leads to more specific
non-acoustic sensor systems that most are familiar with,
for example, non-acoustic current/flow meters, optical
systems, thermistors, dissolved oxygen, plankton samplers, fluorometers, radiometers, magnetic current/flow
meters, seismometers, mass spectrometers, and laser
Raman spectrometers.
State-of-the-art non-acoustic sensor systems are
a summation of five areas: advanced analytical detectors, distributed computing, network technology, automation and power systems. All of these areas are
critical towards the advancement of more capable ocean
sensing and observatories. However, new analytical
functions are our focus and the basis for organizing
the non-acoustic sensors space. Consider, for example, the question as to what scale the sensor system
of interest needs to operate at. Spatial and temporal
elements of the environmental continuum versus the
spatial and temporal continuum of the sensor system
have to be contemplated when looking to derive appropriate sensor-AUV selections.
18.2 Classical Non-Acoustic Ocean Sensors
Acoustics have been a dominant technology in ocean
studies such as mapping and surveys. However, many
ocean spatial and temporal process phenomena require
other sensory modalities to properly access the space,
time, and composition. In the case of particle characterization for size, form, and temporal dynamics, acoustic
systems provide sensing abilities for longer temporal
and spatial scales. In contrast, non-acoustic ocean optical systems provide similar time–space coverage but
also extend to both longer and shorter characterization
time scales. Depending on the platform selected for sensor deployment, optical systems can also extend into
different spatial scales (Fig. 18.1).
Traditional non-acoustic sensors have matured primarily in the physical sensing area. The measurement
of temperature is a great historical example of this maturity process, and it is still prevalent today. Examples
of temperature sensing include the thermistor, thermistor string, and electronic reversing temperature sensor.
Temperature measurement systems of all types, both
general and high precision, are considered mature technologies.
Depth or water column pressure is another common measurement. Examples of pressure measurement
systems include quartz pressure sensors, solid state
diaphragms designed as submersible pressure transducers, such as piezoresistive sensors with an isolated
stainless steel diaphragm in a stainless steel or titanium package. Their uses include wave and tide gauges,
tsunami detection, ocean current surveys, and seabed
subsidence.
Salinity is widely perceived as a fundamental variable in the regulation of natural marine systems. It
is a key parameter in determining seawater physical