At the heart of a BRUVS is a small, inexpensive action camera in a simple but robust underwater housing. This camera is held in a steel frame that also holds a bait arm. At the end of this bait arm is with a mesh bag full of minced pilchards to attract sea life. Lights can be added for night and deep water surveys. Although for many years, this tool has been valuable to capture sealife, in a stationary platform, but how are we surveying the seafloor now and the tools we are engineering for the future, is what I want to focus on now.
Underwater hyperspectral imaging is a relatively new method for characterizing seafloor composition. To date, it has been deployed from moving underwater vehicles, such as remotely operated vehicles and autonomous underwater vehicles. While moving vehicles allow relatively rapid surveying of several 10-1000 m2, they are subjected to short-term variations in vehicle attitude that often compromise image acquisition and quality. During a recent study by IEEE Transactions on Geoscience and Remote Sensing in May 2019, based on supervised classification, 24 spectrally different seafloor materials were detected, including hydrothermal and non-hydrothermal materials, and benthic fauna.
Now you might be googling or asking yourself what those materials are, but I did that work for you so let me help you define those. In broad terms, hydrothermal material includes various crystallized substances from high-temperature aqueous solutions at high vapor pressures. This is leading to some important technological and environmental advantages such as: one-step process for direct production of crystalline ceramic powders, low energy consumption, products with much higher homogeneity than classical solid state processing, versatility in producing oxides, non-oxides and hybrid materials with different morphologies, possibility to be up-scaled to pilot and production levels.
Hydrothermal synthesis crystal
For subaerial purposes, hyperspectral data are typically acquired by hyperspectral imagers on airplanes or satellites. These hyperspectral imagers are passive imagers as they use the sun as a light source for surface illumination. They record the intensity of reflected solar radiation over a wavelength range of 400–2500 nm, and are used in both onshore and offshore settings. Since the technology in unmanned systems has evolved into using ROVs that are operated within a few meters to the seafloor, giving the data collection a huge advantage over aerial or satellite collection. I definitely agree to use an ROV for this method, as well as increasing the capability to recover those materials. The further we are able to explore into deep sea as well as deep space, scientists may have a chance of discovering material that can be used in the absence of something we might be having a shortage of. Pictured below is an example of a couple hyperspectral imagers currently being used in the civilian sector.
If you would like to view the article used for referencing the photographs, I have attached the link below, found through ERAU library.
https://ieeexplore-ieee-org.ezproxy.libproxy.db.erau.edu/document/8587132
