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New system "works with the ocean" to plan best routes for autonomous subs

New system "works with the ocean" to plan best routes for autonomous subs
A new algorithmic system allows AUVs to reach their destinations faster, or to use less power, by identifying and traveling with existing ocean currents (Photo: Stifyn Tonna)
A new algorithmic system allows AUVs to reach their destinations faster, or to use less power, by identifying and traveling with existing ocean currents (Photo: Stifyn Tonna)
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A new algorithmic system allows AUVs to reach their destinations faster, or to use less power, by identifying and traveling with existing ocean currents (Photo: Stifyn Tonna)
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A new algorithmic system allows AUVs to reach their destinations faster, or to use less power, by identifying and traveling with existing ocean currents (Photo: Stifyn Tonna)
The MIT system allows multiple AUVs to follow the currents to reach different targets, while also avoiding obstacles
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The MIT system allows multiple AUVs to follow the currents to reach different targets, while also avoiding obstacles
In a computer test of the MIT system, AUVs reach their various destinations by following existing currents, while also avoiding two "forbidden zones" (ovals at left)
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In a computer test of the MIT system, AUVs reach their various destinations by following existing currents, while also avoiding two "forbidden zones" (ovals at left)
In a computer test of the MIT system, AUVs ride the eddy currents behind an island for a boost of speed
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In a computer test of the MIT system, AUVs ride the eddy currents behind an island for a boost of speed
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Autonomous underwater vehicles, better known as AUVs, are increasingly finding use in applications such as oceanographic research, mapping, military reconnaissance, and deep-sea oil-well maintenance. As these independent underwater robots make their way through the world's oceans, they use GPS transceivers to keep themselves on a predetermined route. When they encounter challenges such as cross-currents, one might assume that their best course of action would be simply to power straight across them, in order to travel the shortest distance possible. Engineers from MIT, however, have developed a system that allows AUVs to reach their destinations sooner, by traveling out of their way to "go with the flow."

The algorithm-based system, developed by MIT's Multidisciplinary Simulation, Estimation, and Assimilation Systems (MSEAS) group, is designed to work not just with individual AUVs, but even with swarms of vehicles following different routes. Besides allowing the subs to identify and follow currents that will get them where they're going more quickly, the system can also calculate oceanic paths optimized for minimum use of energy, or for maximum data collection opportunities.

Besides simply hitching rides with currents, the system may also instruct AUVs to dive under or rise over them. Additionally, it is able to steer them around forbidden "no subs" zones (such as marine ecological reserves), and can even compensate for moving obstacles such as passing ships. Should the unpredictable ocean not behave exactly as the algorithms predicted, the system is also able to identify the discrepancies, and get the AUVs back on course.

The MIT system allows multiple AUVs to follow the currents to reach different targets, while also avoiding obstacles
The MIT system allows multiple AUVs to follow the currents to reach different targets, while also avoiding obstacles

The MSEAS engineers have performed successful tests of the system using computer models, including one in which 1,000 AUVs made their way through a complex area of the Philippines. That area features intricate shorelines, numerous islands, shallows, and shifting currents. The virtual AUVs were launched from different ships, and were heading for different destinations.

Although other teams have tried to devise such systems in the past, study leader Pierre Lermusiaux stated that the algorithms employed were too imprecise, couldn't handle the chaotic real-world conditions in the ocean, or simply required too much computational power to be practical. He added that in the future, his group's system could also be applied to unmanned aerial vehicles, or even to nanobots traveling through the human bloodstream.

More information is available in the video below.

Source: MIT

Optimal paths for automated underwater vehicles (AUVs)

View gallery - 4 images
2 comments
2 comments
Amin Mansouri
Computer models for 1000 of AUV through the intricate area of Philippine shows how much hard work has been done for this great project. Good job!
ralph.dratman
How does that little yellow thing stay out of the way of those big ships?