Autonomous tug trialed in Port of Singapore

A PSA Marine tug master providing feedback on the smart navigation system during a usability test conducted on Wärtsilä’s autonomous ship simulator. Copyright: Wärtsilä.

Wärtsilä and Singapore harbor and terminal towage operator PSA Marine (Pte) Ltd. have successfully completed initial sea trials for the “IntelliTug” project (see earlier story).

The PSA Polaris, a harbor tug owned and operated by PSA Marine, has been retrofitted with a suite of Wärtsilä technology to enable autonomous navigation.

Carried out in Singapore, the trials began in September 2019 They verified the IntelliTug’s capability to avoid a variety of obstacles, including virtual and real-life moving vessels.

The project is a collaboration between Wärtsilä, PSA Marine, classification society Lloyd’s Register, and the Technology Center for Offshore and Marine Singapore (TCOMS). It is co-funded by the Maritime and Port Authority of Singapore’s (MPA) Maritime Innovation and Technology (MINT) Fund.

The trials are Singapore’s first for commercial Maritime Autonomous Surface Ships (MASS) using the MPA MASS “regulatory sandbox,” established to facilitate the testing of MASS and other autonomous technologies in a safe and controlled environment within the Port of Singapore.

AN INTELLIGENT TUG FOR FUTURE OPERATIONS

The PSA Polaris is a 27-meter harbor tug with dual azimuth thruster controls. It has been fitted with a sensor suite, including Wärtsilä’s RS24 near-field high resolution radar and Wärtsilä’s Dynamic Positioning (DP) system, to enable autonomous capabilities. Data collection via the sensors has been ongoing since the start of the project in conjunction with the development of a collision avoidance algorithm.

“PSA Marine is constantly innovating to redefine the capabilities of our tugs. The achievement seen in the IntelliTug project is a testament that with strong partnership, alignment of purpose and the courage to innovate, ideas can be turned into reality. With the incorporation of feedback and experience from our tug masters, the smart technology developed in the IntelliTug project augments our tug masters’ situational awareness and amplifies their capabilities. We will continue to work closely with the stakeholders and look forward to future developments of the project,” said Peter Chew, Managing Director of PSA Marine.

RIGOROUS TESTING FOR AUTONOMOUS DEVELOPMENT

Before sea trials got under way, system integration and digital testing began with the use of Wärtsilä’s autonomous ship simulator. TCOMS has carried out further validation of the various data gathered from the sensor suite, as well as real-world performance of the tug through a physics-based digital twin that incorporated the effects of the physical environment faced in the sea trials. Lloyd’s Register has been closely involved throughout the project to support the development of the trials’ safety case, while collaborating on the human factors and technology design processes.

“Wärtsilä has taken a rigorous, staggered approach to the sea trials, first to prove the fundamental safety and accuracy capabilities of the system, and then moving on to real obstacle-free path planning. It has further progressed to more complicated test cases, previously attempted in digital batch testing and digital first-person simulation. The design of the test cases was a collaborative effort involving Tug Masters and a Master Mariner, with close review and continuous refinement with MPA throughout the project,” says Thomas Brightwell, SACA Software Manager, Wärtsilä.

ABOUT THE SEA TRIALS

During the sea trials, a new smart navigation system — developed during the project in cooperation with PSA Marine’s tug masters — was used to select destinations for the hundreds of test cases carried out. The system allows the user to easily see the routes plotted, with the avoidance of collisions, in real-time. The smart navigation system also sends track and speed commands to the DP system, which drives the vessel along the route safely at varying speeds up to 10 knots. These maneuvers are expected to follow set behaviors and meet success criteria to reach the destination.

At all times, the PSA Marine tug masters were able to determine if the tests were safe to continue and had full control to abort testing at any time where required.

Wärtsilä and PSA Marine will continue development work on the IntelliTug and its systems throughout 2020, working towards continuous deployment of smart capabilities in real-life harbor craft operations to complement and enhance the capabilities and experience of human tug masters.