Page 8 - Ranger Demo

A typical system is shown in (Figure 3) that displays the glider path, location of relevant ships and the status of the vehicle.
Current research is investigating occasions/scenarios when gliders can be fully autonomous, with the safety, security and ocean sampling strategies embedded on the glider in a ‘back-seat driver’ approach.
Figure 4 Gliders operate in a diverse range of environments
Typical sensor payloads measure temperature, conductivity, pressure, oxygen concentration and optical characteristics of the ocean, sampling as often as every few seconds, if required. Other higher power sensors can be added for specific missions, though these will reduce the endurance of the glider.
The use of a buoyancy engine as the critical mechanism for the efficient movement of a glider requires consideration of the density of the ocean in which the glider is operating. To be sure that the glider can rise and fall through the changeable vertical density layers in the ocean gliders generally need to be properly trimmed. Even so, it has been demonstrated that gliders can operate in even the harshest environments, such as close to the Arctic and Antarctic ice edge as shown in (Figure 4).
The Role of Underwater Gliders for Data Collection
Over the past 20 years, underwater gliders have revolutionised ocean science with their ability to measure the internal volume of the ocean and provide near real-time data to scientists. Before this, the ocean science community have relied on dedicated survey ships (such as RRS DISCOVERY for the ocean science community and the RN ECHO class for military purposes). Also fixed moorings (such as the O-SNAP array1) and the ARGO ocean float programme2 to gather data for their research and defence projects. Each of these capabilities still has a key role in ocean science for high-quality dedicated measurements. However, both science and defence need to utilise more flexible and lower-
1 https://www.sams.ac.uk/science/projects/uk-osnap/ 2 https://argo.ucsd.edu/
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