Autonomous drone system could save lives at sea

In recent years, thousands of refugees and migrants have crossed the seas as a result of humanitarian crises around the world. A team of Chalmers University of Technologyin Sweden, is currently developing a fully autonomous drone system that can increase efficiency and speed of response in rescue operations at sea.

In the context of refugee crises and migratory flows, the sea has been a recurrent and risky route. Traveling on fragile or overloaded ships has led to the death of people at sea. In the project ‘Quadcopters, fixed-wing and marine drones for search and rescue‘, a Chalmers team is developing a new kind of fully automated system for search and rescue operations. The system relies on water and air drones working together, using a communications system to independently search an area, alert authorities of people in distress and provide basic assistance before crewed rescue vehicles arrive.

Drone systems working together have the potential to save more lives

The drone system consists of three components working together: a marine catamaran drone called Seacat, which serves as a base for other drones, a fleet of winged aerial drones that survey the surrounding area, and a quadcopter that can approach people in distress and deliver items such as supplies, medical aids or flotation devices. The quadcopter – a drone with four motors and therefore capable of hovering – can carry loads weighing up to around two kilograms.

“The project is based on the simple principle that different drones have different advantages, and by enabling multiple types of autonomous drones to work together, search efficiency and rescue response speed can be significantly improved, with the potential to save more lives,” says Xin Zhao, post-doc in the Fluid Mechanics division at Chalmers.

Tomas Grönstedt, Professor in the Fluid Dynamics Division, says:

“Furthermore, the system could – in principle – be linked to any public service or volunteers who could provide some form of assistance.

Automatic battery charging and launching the next stage

The marine drone, Seacat, provides an Internet uplink as well as a local communication link which is used to coordinate the flying drones. It also includes a launch pad for fixed-wing drones. All airborne drones are equipped with cameras and a positioning system. All drones can move completely autonomously – the marine drone follows a predefined route with a closed loop. Fixed-wing drones are automatically assigned to search areas based on an intelligent algorithm that makes the best use of the number of available drones. When a fixed-wing drone detects objects in the water, the quadcopter is sent to the scene to take pictures. The photographs can then be sent to a rescue center on land via the marine drone. The rescue center, for its part, can send the quadcopter with supplies. When one of the Winged Drones runs out of battery, it is disabled and lands in the water near the Seacat Drone, where it can be picked up and recharged automatically, then returned.

“So far, we have successfully completed a quadcopter landing on Seacat, and the winged drones have been built and are being evaluated,” says Ola Benderius, associate professor in the Autonomous Vehicles and Systems Engineering Division, who also led the project.

“As part of the continuation of the project, we will assemble the system and test it in its entirety at sea.”

The drone system was developed in collaboration between the Vehicle Mechanics and Autonomous Systems Division and the Fluid Dynamics Division of the Department of Mechanics and Maritime Sciences.

Marine drone and wing drones are designed from the ground up, built and tested at Chalmers.

The team includes Tomas Grönstedt, Xin Zhao, Isak Jonsson and Carlos Xisto from the Division of Fluid Dynamics, Ola Benderius from the Division of Vehicle Mechanics and Autonomous Systems in the Department of Mechanics and Marine Sciences, Leif Eriksson from the Earth Sciences and Remote Sensing Division of the Space, Earth and Environment Department and Christian Berger of the Software Engineering Division of the Computer Science and Engineering Department.

The project is being executed within the research infrastructure of Chalmers, Revere, with funding from the Transport Area of ​​Advance. The project will end in September 2022.