December 2023

NJORD CHALLENGE 2023 TECHNICAL REPORT-TEAM ARITRA

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.

Dynamic Obstacle Avoidance task, Day 3, Njord 2023

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.

The Aritra Team of IIT Madras at Award ceremony

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.

Visualization of Channel Navigation task, Day 1, Njord 2023

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.

Team Aritra’s ASV being tested in Trondheim River

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.