Mohammed Ibrahim M, Amar Nath Singh, Akash V, Rakshin Ramesh, IEEE OES Madras Chapter
The Aritra Team of IIT Madras has won the Njord Challenge. We submit the report in appreciation of the support provided by IEEE OES.

Abstract— Aritra is a marine autonomy competition team from Marine Autonomous Vessels (MAV) LABS, Dept. of Ocean Engineering, IIT Madras. Our autonomous surface vehicle (ASV) is a catamaran autonomous boat manufactured in Central Fabrication Facility in IIT Madras by Aritra Team in order to participate in Njord Challenge 2023. The team includes 3rd year undergraduates Mohammed Ibrahim, Amar Nath singh, Akash V, Rakshin Ramesh from department of ocean engineering.
1. IIT MADRAS
Indian Institute of Technology (IIT) Madras is known both nationally and internationally for excellence in technical education, basic and applied research, innovation, entrepreneurship and industrial consultancy. The Institute is proud to bear the laureate of being the No.1 engineering university in India. More recently, IIT Madras has been given the title of Institute of Eminence.
2. MAV LAB (Marine Autonomous Vessels lab)
One of the finest laboratories in IIT Madras has been innovating in the field of marine autonomy from 2019. Major works include Hydrodynamic Response Analysis tool (Hydra) for prediction of dynamic motion of ships during its service life, Data driven control of ASV with Deep Reinforcement Learning for path following and obstacle avoidance with agents such as DQN, DDPG and PPO in the presence of unmodelled dynamics and environmental disturbances. Data driven system identification of Maneuvering Model using free running model testing is one of the major works by MAV Labs.

3.NJORD CHALLENGE
Njord – The Autonomous Ship Challenge is a student driven competition held in Trondheim. They aim to give students the opportunity to challenge themselves and put theory into practice, gaining valuable experience on their journey. Njord’s mission is to inspire students to become world leading engineers in maritime autonomous solutions. Njord was established in the spring of 2019 by two students, Paal Arthur S. Thorseth and Kaja Juel Solheim, and Innovation Manager Jan Onarheim from NTNU – Norwegian University of Science and Technology.
4.COMPETITION OVERVIEW
The Njord Challenge spanned three days, featuring a range of tasks, including maneuvering, docking, and obstacle challenges. Each day presented specific challenges, and teams were assessed by a specialized jury. This rigorous competition allowed teams to showcase their skills in marine autonomy while being evaluated on criteria such as accuracy, efficiency, and innovation, providing a comprehensive assessment of their capabilities.
Despite being a smaller team, Team Aritra, guided by Professor Abhilash Sharma, Dr. M A Atmanand supported by sponsors like IEEE OES and the ROYAL NORWEGIAN EMBASSY New Delhi, clinched the 3rd prize in a fiercely competitive field that included MIT and other top international teams.
The competition days were a test of resilience. Overcoming hurdles like battery issues and unfavorable weather conditions, they adapted and learned from each experience. Their outstanding performance in the obstacle avoidance challenge set them apart, earning them the Sustainability Award and a cash prize of 10,000 NOK.
Looking forward, Team Aritra’s sights are set on future challenges, including the Virtual Robotics Competition by RoboNation and RobotX. Their journey has not only expanded their technical knowledge but also their international connections.
In conclusion, Team Aritra’s remarkable journey at the Njord Autonomy Challenge showcases the power of dedication, innovation, and collaboration in the realm of marine autonomy. Their story inspires and highlights India’s growing presence in this field, emphasizing the importance of pushing boundaries and forging global connections in pursuit of cutting-edge marine technology.

5.TECHNICAL DETAILS
Our approach involves YOLO V8 Nano for buoy detection, chosen for its speed and accuracy. Initially, we considered clustering point clouds for detection, but we opted for the YOLO model, trained with provided and generated CAD model datasets.
We employ a PD controller with multiple modes for precision. The Behavior Planner selects the appropriate control and guidance strategies for tasks, including collision avoidance through LiDAR. We translate cardinal markers for navigation tasks.
Our testing strategy encompasses simulations (VRX Gazebo, RVIZ) and real-world evaluations in controlled facilities. Modularity allows independent ground testing.
We opted for a stable catamaran design with flat-bottom displacement hulls, advantageous for thruster mounting. Aluminum brackets connect hulls and serve as control box platforms. Four thrusters in an X configuration grant independent surge, sway, and yaw control.
Our electrical system is power-efficient and modular, with three 4-cell 14.8V batteries, a common kill-switch, and buck converters for voltage regulation. Sensors are powered from the Jetson Nano, except for the LiDAR. The IP box operates within a power range of 15 to 20 Watts.
In summary, our approach encompasses robust object detection, precise guidance control, adaptable odometry, smart testing strategies, a well-designed vessel, efficient thruster configuration, and a thoughtful electrical system. These elements underscore our commitment to building a versatile and reliable autonomous vessel.

6.conclusion
Participating in the njord autonomy challenge has been an incredible learning experience for us. The challenges we faced during the competition, from technical hiccups to rapidly changing norwegian weather, have taught us invaluable lessons that will guide us in our future projects.
One of the most eye-opening aspects of this competition was witnessing even established teams struggle due to norway’s unpredictable climate.
Meeting people and companies with a deep interest in marine autonomy was truly inspiring. It reinforced our commitment to continue down this path of innovation. It also revealed that india is right there on the front lines of marine autonomy development alongside other nations.
Through Njord, we’ve forged international connections that will undoubtedly shape our future endeavors. These collaborations will foster innovation and help us contribute meaningfully to the global marine autonomy community.
As we look ahead, we’re eagerly anticipating the possibility of participating in Njord 2024. Our Njord journey has been transformative, and we’re excited to continue pushing the boundaries of marine autonomy in the years to come.


Dr. James V. Candy is the Chief Scientist for Engineering and former Director of the Center for Advanced Signal & Image Sciences at the University of California, Lawrence Livermore National Laboratory. Dr. Candy received a commission in the USAF in 1967 and was a Systems Engineer/Test Director from 1967 to 1971. He has been a Researcher at the Lawrence Livermore National Laboratory since 1976 holding various positions including that of Project Engineer for Signal Processing and Thrust Area Leader for Signal and Control Engineering. Educationally, he received his B.S.E.E. degree from the University of Cincinnati and his M.S.E. and Ph.D. degrees in Electrical Engineering from the University of Florida, Gainesville. He is a registered Control System Engineer in the state of California. He has been an Adjunct Professor at San Francisco State University, University of Santa Clara, and UC Berkeley, Extension teaching graduate courses in signal and image processing. He is an Adjunct Full-Professor at the University of California, Santa Barbara. Dr. Candy is a Fellow of the IEEE and a Fellow of the Acoustical Society of America (ASA) and elected as a Life Member (Fellow) at the University of Cambridge (Clare Hall College). He is a member of Eta Kappa Nu and Phi Kappa Phi honorary societies. He was elected as a Distinguished Alumnus by the University of Cincinnati. Dr. Candy received the IEEE Distinguished Technical Achievement Award for the “development of model-based signal processing in ocean acoustics.” Dr. Candy was selected as a IEEE Distinguished Lecturer for oceanic signal processing as well as presenting an IEEE tutorial on advanced signal processing available through their video website courses. He was nominated for the prestigious Edward Teller Fellowship at Lawrence Livermore National Laboratory. Dr. Candy was awarded the Interdisciplinary Helmholtz-Rayleigh Silver Medal in Signal Processing/Underwater Acoustics by the Acoustical Society of America for his technical contributions. He has published over 225 journal articles, book chapters, and technical reports as well as written three texts in signal processing, “Signal Processing: the Model-Based Approach,” (McGraw-Hill, 1986), “Signal Processing: the Modern Approach,” (McGraw-Hill, 1988), “Model-Based Signal Processing,” (Wiley/IEEE Press, 2006) and “Bayesian Signal Processing: Classical, Modern and Particle Filtering” (Wiley/IEEE Press, 2009). He was the General Chairman of the inaugural 2006 IEEE Nonlinear Statistical Signal Processing Workshop held at the Corpus Christi College, University of Cambridge. He has presented a variety of short courses and tutorials sponsored by the IEEE and ASA in Applied Signal Processing, Spectral Estimation, Advanced Digital Signal Processing, Applied Model-Based Signal Processing, Applied Acoustical Signal Processing, Model-Based Ocean Acoustic Signal Processing and Bayesian Signal Processing for IEEE Oceanic Engineering Society/ASA. He has also presented short courses in Applied Model-Based Signal Processing for the SPIE Optical Society. He is currently the IEEE Chair of the Technical Committee on “Sonar Signal and Image Processing” and was the Chair of the ASA Technical Committee on “Signal Processing in Acoustics” as well as being an Associate Editor for Signal Processing of ASA (on-line JASAXL). He was recently nominated for the Vice Presidency of the ASA and elected as a member of the Administrative Committee of IEEE OES. His research interests include Bayesian estimation, identification, spatial estimation, signal and image processing, array signal processing, nonlinear signal processing, tomography, sonar/radar processing and biomedical applications.
Kenneth Foote is a Senior Scientist at the Woods Hole Oceanographic Institution. He received a B.S. in Electrical Engineering from The George Washington University in 1968, and a Ph.D. in Physics from Brown University in 1973. He was an engineer at Raytheon Company, 1968-1974; postdoctoral scholar at Loughborough University of Technology, 1974-1975; research fellow and substitute lecturer at the University of Bergen, 1975-1981. He began working at the Institute of Marine Research, Bergen, in 1979; joined the Woods Hole Oceanographic Institution in 1999. His general area of expertise is in underwater sound scattering, with applications to the quantification of fish, other aquatic organisms, and physical scatterers in the water column and on the seafloor. In developing and transitioning acoustic methods and instruments to operations at sea, he has worked from 77°N to 55°S.
René Garello, professor at Télécom Bretagne, Fellow IEEE, co-leader of the TOMS (Traitements, Observations et Méthodes Statistiques) research team, in Pôle CID of the UMR CNRS 3192 Lab-STICC.
Professor Mal Heron is Adjunct Professor in the Marine Geophysical Laboratory at James Cook University in Townsville, Australia, and is CEO of Portmap Remote Ocean Sensing Pty Ltd. His PhD work in Auckland, New Zealand, was on radio-wave probing of the ionosphere, and that is reflected in his early ionospheric papers. He changed research fields to the scattering of HF radio waves from the ocean surface during the 1980s. Through the 1990s his research has broadened into oceanographic phenomena which can be studied by remote sensing, including HF radar and salinity mapping from airborne microwave radiometers . Throughout, there have been one-off papers where he has been involved in solving a problem in a cognate area like medical physics, and paleobiogeography. Occasionally, he has diverted into side-tracks like a burst of papers on the effect of bushfires on radio communications. His present project of the Australian Coastal Ocean Radar Network (ACORN) is about the development of new processing methods and applications of HF radar data to address oceanography problems. He is currently promoting the use of high resolution VHF ocean radars, based on the PortMap high resolution radar.
Hanu Singh graduated B.S. ECE and Computer Science (1989) from George Mason University and Ph.D. (1995) from MIT/Woods Hole.He led the development and commercialization of the Seabed AUV, nine of which are in operation at other universities and government laboratories around the world. He was technical lead for development and operations for Polar AUVs (Jaguar and Puma) and towed vehicles(Camper and Seasled), and the development and commercialization of the Jetyak ASVs, 18 of which are currently in use. He was involved in the development of UAS for polar and oceanographic applications, and high resolution multi-sensor acoustic and optical mapping with underwater vehicles on over 55 oceanographic cruises in support of physical oceanography, marine archaeology, biology, fisheries, coral reef studies, geology and geophysics and sea-ice studies. He is an accomplished Research Student advisor and has made strong collaborations across the US (including at MIT, SIO, Stanford, Columbia LDEO) and internationally including in the UK, Australia, Canada, Korea, Taiwan, China, Japan, India, Sweden and Norway. Hanu Singh is currently Chair of the IEEE Ocean Engineering Technology Committee on Autonomous Marine Systems with responsibilities that include organizing the biennial IEEE AUV Conference, 2008 onwards. Associate Editor, IEEE Journal of Oceanic Engineering, 2007-2011. Associate editor, Journal of Field Robotics 2012 onwards.
Milica Stojanovic graduated from the University of Belgrade, Serbia, in 1988, and received the M.S. and Ph.D. degrees in electrical engineering from Northeastern University in Boston, in 1991 and 1993. She was a Principal Scientist at the Massachusetts Institute of Technology, and in 2008 joined Northeastern University, where she is currently a Professor of electrical and computer engineering. She is also a Guest Investigator at the Woods Hole Oceanographic Institution. Milica’s research interests include digital communications theory, statistical signal processing and wireless networks, and their applications to underwater acoustic systems. She has made pioneering contributions to underwater acoustic communications, and her work has been widely cited. She is a Fellow of the IEEE, and serves as an Associate Editor for its Journal of Oceanic Engineering (and in the past for Transactions on Signal Processing and Transactions on Vehicular Technology). She also serves on the Advisory Board of the IEEE Communication Letters, and chairs the IEEE Ocean Engineering Society’s Technical Committee for Underwater Communication, Navigation and Positioning. Milica is the recipient of the 2015 IEEE/OES Distinguished Technical Achievement Award.
Dr. Paul C. Hines was born and raised in Glace Bay, Cape Breton. From 1977-1981 he attended Dalhousie University, Halifax, Nova Scotia, graduating with a B.Sc. (Hon) in Engineering-Physics.