First Free-Floating Autonomous Underwater Construction Robot

Diving Deep: The Future of Robotic Underwater Construction

Imagine a world where robots can effortlessly build various underwater infrastructures, such as foundations for offshore wind farms, entirely on their own without human intervention. Thanks to this project, we are taking a considerable step towards making this a reality. Researchers have introduced an autonomous underwater vehicle (AUV) that carries out construction work using cement blocks.

Energy-Efficient Robotic Underwater Construction

Having a robot that builds structures and handles heavy materials underwater can be energy-intensive. However, this is no ordinary robot, it’s a fully independent system that can adjust its buoyancy (think of it as an underwater balloon that can inflate or deflate to either sink or float) to handle heavy materials underwater. To manage its buoyancy, the AUV stores compressed air in tanks similar to those used for scuba diving.

The ability of the robot to blend the right amount of battery power with fine-tuned buoyancy allows it to lift and move heavy blocks efficiently. Thus, this AUV is well-suitable for constructing larger structures under the sea without needing a ton of energy.

Clever AUV Construction Techniques

The real magic lies in the design of the manipulator and the utilization of special cement blocks. 

These cement blocks are designed to fit together despite some misalignments. This error-correcting property is possible because of the integration of cone-like inserts that help correct any misalignments during construction. These inserts are crucial for ensuring that each layer of blocks aligns correctly with the one above, leading to a stable and sturdy structure. 

The AUV also has a simple but effective robotic arm — a one-degree-of-freedom manipulator that is capable of lifting the blocks easily and efficiently. The weight of the block helps tighten the grip of the manipulator's claws; thus ensuring a firm hold that automatically adjusts to handle the object without slipping. This manipulator is also designed to have error-correcting capability, allowing it to place blocks precisely. This capability eliminates the need for complex control and sensing methodologies for lifting or placing the blocks. 

Looking to the Future of Underwater Construction by AUVs

Building underwater is no easy task, but with this AUV, we have a significant first step. Although there is still much room for improvement and development, these advancements will make the AUV even more capable and versatile for various underwater construction tasks.

Enhancements may include methods that enable the robot to move faster and better perceive its environment to adapt to unexpected changes (e.g., shifting currents or unexpected obstacles). A limitation in advancing such AUVs relates to the underwater hardware. Although there have been significant advancements in underwater technology, such as thrusters, these are still insufficient for such AUVs to perform complex tasks efficiently and be practically deployed in real-world scenarios.