*The following is a tentative list of keynote speakers presented alphabetically by last name.
Tomonari Akamatsu
Title: Senior Researcher (Professor)
Institution: Research Organization for Nano & Life Innovation, Waseda University, Japan
Additional Role: Director of Ocean Policy Research Division, Sasakawa Peace Foundation, Japan
Tomonari Akamatsu
Progresses of underwater acoustic technologies
Tomonari Akamatsu, Research Organization for Nano & Life Innovation, Waseda University
Introduction
In underwater environments where electro-magnetic waves and light cannot travel far, sound waves have long been used for exploration and communication. This lecture will introduce the recent developments of active technologies, which emit sound waves to detect reflections from objects, and passive technologies, which detect sounds from phonating objects. It will also explore future technological prospects.
Development of Active Technologies
In active technologies, a major turning point has been the application of multi-channel and wide-band methods. For example, multibeam sonar equips multiple receiving elements for the beam forming to separate reflected sounds from various directions as well as the echo delay time, which is enabling the visualization of 3D object distributions underwater. This has been applied in mapping seabed topography, fish school shapes, subsurface exploration for mining using air guns, and even underwater visual-like imaging using acoustic lenses. Additionally, wide-band technologies provide various type of target information in addition to the location and time. For example, power spectrum shape of wide-band echo from a fish can be used for the species identification. Impulse response of a target could reflect the internal structure of a fish that is the bio-mimetic echosounder of dolphin sonar. Wide-band frequency modulated signals also contribute the fine time and spatial resolutions to obtain fine imaging of seabed and fish schools.
Ocean sound propagation experiments by Munk and others in 1991 demonstrated that low-frequency underwater sounds can travel thousands of kilometers in the sound channels. This technique has been applied to observe average water temperature and current speed based on the sound travel time between two acoustic stations having a transmitter and a receiver. One pinnacle of the application of this technology is ocean acoustic tomography, which calculates the 3D distribution of water temperature and current speeds by solving simultaneous equations of multiple sound paths.
Underwater communication is challenging theme, which is even difficult comparing with space communication. The speed of sound is significantly slower than light and is more susceptible due to multiple reflections and attenuation. Techniques like phase modulation and convolution processing have been employed to mitigate these effects. The improvement of the distance and the speed of communication is an essential technology for future underwater engineering for controlling autonomous underwater vehicles (AUVs) and other independent underwater robots.
Development Passive Technologies
Passive technology development has been largely driven by the detection of submarines. During the Cold War, a network known as SOSUS (Sound Surveillance System) was deployed across the Atlantic. Interestingly, what was once considered noise turned out to be the vocalizations of whales. After the Cold War, underwater acoustic technologies were made available for civilian use, and what was once regarded as noise became the target of observation. Not only marine mammals like whales, dolphins, and dugongs, but also sound-producing species such as fish and crustaceans, are now being monitored using passive technologies. These techniques are widely used globally for environmental assessments of the oceans. For examples, long-term continuous monitoring of presence of odontocetes using high frequency pulse event recorders have been used for the impact assessment of offshore windfarm development.
A more recent development that has attracted attention is Distributed Acoustic Sensing (DAS), which uses weak reflections from lattice defects in fiber optic cables to measure underwater sound pressure. Though the sensitivity is still insufficient, existing fiber-optic communication cables can be used as hydrophone arrays to detect surrounding sound sources.
Future Issues and Anticipated Technologies
Ocean is no longer out of reach domain. Underwater Domain Awareness is strongly demanded for the sustainable use of ocean. For active technologies, precise mapping and wide-band communication in long range is needed. Localization in the water like an underwater GPS will be required for the operation of underwater robots. For passive technologies, identifying the sources is a big issue. Annotated reference data of phonating targets is needed. The rising underwater noise levels from various human activities have become an international concern due to their impact on marine life. The International Maritime Organization has already set non-mandatory guidelines for ship noise. In coming future, two major ocean developments are the floating type offshore windfarms and deep-sea mining. The issue is that we do not know the baseline data of ocean noise and status of intact marine ecosystem in far offshore and deep waters. This means no control data is available to assess the impact of future ocean developments. Ocean engineering should care the ocean ecosystems to meet sustainable development goad 14th. Active and passive acoustic technologies will provide compromised solutions.
Eiichiro Araki
Title: Senior Researcher
Institution: Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Japan
Bruce M. Howe
Title: Research Professor
Institution: Ocean and Resources Engineering Department, School of Ocean and Earth Science and Technology, University of Hawaii
Hanumant Singh
Title: Professor
Institution:
Electrical and Computer Engineering
Jointly Appointed Mechanical and Industrial Engineering
Program Director, Master of Science in Robotics
Northeastern University College of Engineering
Hanumant Singh
Title
The Role of Machine Learning on Underwater Robotics and Marine Imaging
Abstract
Machine Learning algorithms are becoming ubiquitous in the world of computer vision and robotics. In this talk, I will explore the role of ML and contrast such methods with geometric / physics based techniques. Using real world examples from the marine and polar domains I will show how these methods complement each other and the unsolved problems that the community needs to tackle. In particular I will focus on the highly unstructured low contrast, high backscatter environments that have presented challenges to the research community including imaging in turbid waters, at hydrothermal vents and for icebergs and marine terminating glaciers.
Bio
Hanumant Singh is a Professor at Northeastern University. He received his Ph.D. from the MIT WHOI Joint Program in 1995 after which he worked on the Staff at Woods Hole Oceanographic Institution until 2016 when he joined Northeastern. His group has designed and built the Seabed AUV and the Jetyak ASV, dozens of which are in use for scientific and academic research across the globe. His research focus is in the area of SLAM, 3D reconstruction, and Imaging for field robotics, especially in the context of marine and polar environments. He has participated in 65 expeditions in all of the world’s oceans in support of Marine Geology, Marine Biology, Deep Water Archaeology, Chemical Oceanography, Polar Studies, and Coral Reef Ecology. His work has been featured in National Geographic Magazine, the BBC, the New York Times, Wired Magazine, Discover Magazine and other news and television outlets around the world.
In collaboration with his students his awards include the ICRA Best Student Paper Award, the Sung Fu Memorial Best IEEE Transactions on Robotics Paper Award and Best Paper Awards at the Oceans Conference and at AGU. He is a Fellow of the IEEE and has received the IEEE Oceanic Engineering Society Lifetime Achievement Award for his contributions to the design and use of Autonomous Marine Systems.
Fumin Zhang
Title: Chair Professor
Institution: Department of Electrical and Computer Engineering and Department of Mechanical and Aerospace Engineering, Hong Kong University of Science and Technology (HKUST), Hong Kong
Additional Role:
- Director of Cheng Kar-Shun Robotics Institute (CKSRI), HKUST
- Director of HKUST Cheng Kar-Shun Robotics Institute
Fumin Zhang
Title
Motion Tomography: Learning Ocean Flow from Marine Vehicle Trajectories
Abstract
Recent technology advancements are enabling long term autonomy solutions for swarms of marine robots, aerial vehicles, and satellites to form mobile sensor networks to collect information from land and ocean. This talk addresses the fundamental path following behaviors of marine vehicles under the guidance of ocean models, which is motivated by experimental work on navigating ocean gliders. Experimental data consistently suggests that the navigation error is caused by unknown ocean flow. The method of motion tomography (MT) is proposed to learn the unknown ocean flow from the navigation error along the vehicle trajectories. This method fuses the data collected by multiple marine vehicles along their paths to formulate an “inverse problem” that has been the core problem underlying medical CT imaging. By solving this inverse problem, a high-resolution spatial map of ocean flow in the volume traversed by the vehicles can be reconstructed. Motion tomography provides a “directly measured” spatial map of ocean flow, which can be leveraged by path planning and following controllers on-board marine vehicles to reduce the navigation error. However, due to the limited spatial resolution of the flow map, the tracking performance of the marine vehicles are bounded by a smallest possible error.
Dr. Fumin ZHANG is Chair Professor and Director of the Cheng Kar-Shun Robotics Institute at the Hong Kong University of Science and Technology, serving as Acting Head for the Department of Mechanical and Aerospace Engineering. He is also Dean’s Professor adjunct in the School of Electrical and Computer Engineering at the Georgia Institute of Technology. He received a PhD degree in 2004 from the University of Maryland (College Park) in Electrical Engineering and held a postdoctoral position in Princeton University from 2004 to 2007. His research interests include mobile sensor networks, maritime robotics, control systems, and theoretical foundations for cyber-physical systems. He received the NSF CAREER Award in September 2009 and the ONR Young Investigator Program Award in April 2010. He is currently serving as the co-chair for the IEEE RAS Technical Committee on Marine Robotics, associate editors for IEEE Transactions on Automatic Control, and IEEE Transactions on Control of Networked Systems, IEEE Journal of Oceanic Engineering, and International Journal of Robotics Research. He is Fellow of IEEE.
