7. Gliders
In an earlier blog article, we discussed various types of autonomous underwater vehicles (AUVs). In this article, we hope to highlight a specific type of AUV that has become a popular tool for collecting oceanographic data — they are called “Ocean gliders” and they can navigate through the water column for extended periods of time, collecting data on a variety of oceanographic variables.
Ocean gliders are typically designed to operate for weeks or months at a time, collecting data along pre-programmed trajectories or following adaptive sampling algorithms. The vehicles are buoyancy-driven and use small changes in their weight to control their vertical position in the water column. The gliders have wings, which allow them to move forward through the water. The wings also generate lift, which is used to maintain the glider’s depth.
The glider’s propulsion system consists of a battery-powered motor that drives a pump, which moves water in and out of the vehicle’s buoyancy chamber. By pumping water in and out of the chamber, the glider can adjust its buoyancy, allowing it to move up and down in the water column. The glider’s control system uses sensors to measure the vehicle’s surroundings (such as pressure and temperature), allowing it to make adjustments to its trajectory and maintain a stable position in the water.
One of the key advantages of ocean gliders is their ability to collect data in areas that are difficult or impossible to access using traditional ship-based sampling. The gliders are capable of covering large areas of the ocean, making them ideal for studying phenomena such as ocean eddies and fronts, which can be highly variable and difficult to sample using conventional methods. The gliders can also be used to monitor changes in ocean conditions over time, providing valuable data for understanding the impacts of climate change on the ocean.
Ocean gliders are equipped with a range of sensors that measure environmental variables, such as a CTD. Some gliders are also equipped with sensors that measure the concentration of dissolved oxygen, nutrients, and other chemical species in the water. The data collected by the gliders is transmitted to shore via satellite or other means for telemetry, allowing scientists and other stakeholders to monitor the vehicle’s progress in real-time and analyze the data as it is collected.
In addition to their scientific applications, ocean gliders are also used for a variety of commercial and military applications. The vehicles can be used for underwater surveillance, oil and gas exploration, and oceanographic mapping, among other applications. The gliders are also used for search and rescue operations, as they can be quickly deployed to search for missing or stranded persons in the water.
Despite the advantages of ocean gliders, there are many challenges that constrain their operational reach. While gliders are are indeed designed for autonomous operation for weeks or months, the current state-of-art gliders still require some level of human supervision and occasional intervention. These operations can significantly increase the cost of sampling and can also pose a security risk in the defense context. For instance, in 2016, an US oceanographic gilder was intercepted by the Chinese PLA Navy during its recovery process. There is a need to provide cost-effective power at sea in order to increase gliders’ measurement payload and lower the recovery/maintenance frequency. Additional power supply via glider docking and charging can also enable data transfer, backup and upload. These new capabilities can sustain gliders’ operational range and maintain a more constant presence, which are critical features for ocean sampling in both commercial and defense settings.
Ocean gliders are a powerful tool for collecting oceanographic data. These autonomous vehicles are capable of navigating through the water column for extended periods of time. The data collected by ocean gliders is critical for understanding the physical, chemical, and biological properties of the ocean, and for monitoring changes in ocean conditions over time. As the technology continues to evolve, ocean gliders are likely to remain a key tool for oceanographic research in the future.
Please visit www.oceanmotion.tech to learn more.
The editing of this article was powered by deepsage.ai
References
