If a boat gets stuck at the mouth of a port, as has already happened in several anchorages in the Maresme due to the accumulation of sand, and prevents circulation, the deployment of rescue has very high costs. That is why some port facilities, such as Marina Premià, opt for prevention and to maintain periodic control of the sandbanks that accumulate in the port environment, a procedure they carry out with remote-controlled marine electric robots.
The seabots are small 40-centimeter electric contraptions equipped with as many sensors as the occasion requires, which allow them to monitor the seabed and offer combined information and a digitized three-dimensional map of the explored area at the moment. The application is used in hydrography, quantification of blue carbon and control of the environment and the marine ecosystem, such as in Posidonia plantations, the fundamental marine plants in the balance of biodiversity in the Mediterranean.
In the case of the Maresme, the dynamics of the coast have changed abruptly, with fewer easterly storms, for which the ports are better protected. However, when the intensity of the westerly storms increases, incidents also worsen, such as the accumulation of sand and sediments in the mouths.
The port concession contract, as a general rule, establishes the obligation of the awarded companies to dredge not only the mouths, but also to transfer the sand from the beaches next to the breakwaters, since they act as artificial barriers that interrupt the natural dynamics of sediments. The robots provide a concise mapping of the sandbars.
The seabots, as detailed by the company’s executive director, Pau Guasch, are also used in research, such as, for example, the collaborations they maintain with the Marine and Environmental Hydraulic Engineering Laboratory of the Polytechnic University of Catalonia (UPC), which continues with an investigation into the effect of storms and climate change on the Catalan coast.
The seabots send the detailed information and, according to the data captured by the installed sensors, immediately issue the digitized information with which the three-dimensional map of the seabed is formed. So, for example, “this week in the port of Tarragona they quickly and effectively located the lost anchor of a large merchant ship”, which they were then able to recover with specialized cranes. “Without the robots, the detection costs would have been very high”, since at least four divers would be needed, as required by the regulations.
Public institutions and environmental consultants have also taken an interest in the use of marine robots to monitor the state of marine infrastructure. For example, to find out the effect of storms on the maritime collectors, several navigations are carried out with which a digital twin is obtained with images that allow detecting the modifications and acting accordingly in anticipation of setbacks.
Other applications in which robots are involved are the detection of pollutants and mini-plastics and the collection of samples to analyze water quality. They are also used to monitor aquaculture farms and navigable rivers or, more recently, in the Sau swamp, where human intervention in certain circumstances is not feasible.
