The Internet of Underwater Things promises to revolutionize our interaction with the submarine environment.
Today the Internet of Things (IoT) is rapidly spreading across the terrestrial and aerial worlds. This network of so-called smart devices, each enabled with electronics, software, sensors, actuators and network connectivity, is carrying data on an ever greater scale.
As the technology develops, the commercial and noncommercial benefits are increasingly compelling. Yet even as the IoT connects everything from home thermostats and refrigerators to shipping containers and drones, this web of wireless signals has yet to pervade the underwater environment.
The development of an Internet of Underwater Things (IoUT), transmitting data throughout the ocean could make possible a system of roaming, autonomous vehicles and underwater sensors, all communicating with each other and relaying information to networks above the surface. This could be used for a wide range of submarine tasks, from pipeline repair and shipwreck surveys to seismic detection and ecological monitoring.
“There are an incredible number of possibilities for IoUT and autonomous underwater vehicles (AUVs),” says Richard Mills, director of sales at Norwegian AUV and marine robot developer Kongsberg Maritime. “The technology has finite bounds, but new applications are only limited by our imagination.”
Clusters of AUVs
Before the IoUT can become a practical and commercial reality, researchers face a raft of challenges. Chief among these is the fact that the electromagnetic waves used by conventional WiFi networks only travel a few centimeters in water.
The IoUT could be used for pipeline repair, shipwreck surveys, seismic detection and ecological monitoring.
While optical modems currently enable fairly large bandwidth communications between two or more closely-spaced underwater devices, acoustic signals are often chosen to communicate over long submarine distances. But these channels offer very limited bandwidth. Background noise, from both marine life and anthropogenic activity, can also lead to interference.
“The IoUT will require levels of interconnectivity not typically achievable with conventional underwater communications,” says Joe Tena, global business manager of Marine Robotics Systems with UK-based AUV instrumentation supplier Sonardyne. A research team based at Rome’s Sapienza University believes that one solution may be the use of clusters of AUVs which interact while performing different tasks. Flotillas of these vehicles would exchange information using low-power acoustic signals, similar to the way marine mammals such as whales and dolphins communicate and collaborate.
The Sapienza team is currently working on new software and hardware for use in AUVs that can transmit images from the seabed using acoustic waves and dock with others for recharging. Surface buoys that receive GPS signals provide navigational capacity.
Smart AUV collaboration also has been facilitated by David Lane, a professor of autonomous engineering at Edinburgh’s Heriot-Watt University, who has developed a version of Dropbox for IoUT applications. Using this system, AUVs with different capabilities can share information and multitask.
AUVs will replace many remotely operated vehicles (ROVs) in the near future. Their ability to function without human intervention is already a huge advantage where no manipulation of objects is required. The cost of deploying an AUV is significantly lower than that of an ROV, while their autonomous nature minimizes the human effort needed during missions.
Defense and Research Applications
As the IoUT develops, it will facilitate new ways for AUVs to interact with the subsea environment. Such vehicles increasingly will be used to harvest data from instruments on the seabed for scientific monitoring and surveying oilfield infrastructure.
There is an increasing number of deep-water and under-ice research projects and new applications in defense.
“We will see acoustic communications transmitting information to AUVs over long distances, while optical modems enable data transfer between sensors and vehicles over shorter distances,” says Sonardyne’s Tena. “The entire network will enable the provision of near-real-time updates to surface-based operators.”
With better submarine communications, the use of AUVs is already diversifying. There is an increasing number of deep-water and under-ice research projects, and new applications in defense and shallow-water seabed imagery.
“There has already been some success with swarms of small AUVs,” says Kongsberg’s Mills. “Now, we are about to see the results of a swarm of survey-class deep-water AUVs. The remote operation and supervision of launch, dive and recovery of AUVs from an unmanned surface vehicle may also happen sooner than many expect.”