The US Defense Advanced Research Project Agency (DARPA) has issued a request for proposals (RFP) for the development of an undersea autonomous system that can navigate to and physically manipulate objects on the sea floor.
The autonomous unmanned underwater vehicles are to be developed as part of the agency’s Angler program which aims to improve the performance of underwater robots.
Angler seeks to migrate advancements from terrestrial and space-based robotics, terrestrial autonomous manipulation, and underwater sensing technologies into the realm of undersea manipulation, with specific focus on long-distance, seabed-based missions.
Specifically, the program aims to discover innovative autonomous robotic solutions capable of navigating unstructured ocean depths, surveying expansive underwater regions, and physically manipulating manmade objects of interest.
Exploration and manipulation at the seafloor remains one of the most challenging earthbound domains, despite breakthrough advancements in terrestrial robotics, space robotics, and underwater sensing, DARPA says. While the seafloor can be assumed to be gently sloping sand dunes, the presence of natural and man-made obstacles significantly increases the complexity of search and navigation tasks.
For example, large-scale structures, such as reefs, submarine vents, and fissures require careful traversal. Further, natural features can change at a much faster rate than traditional terrestrial environments, challenging classical perception techniques that are wholly dependent on feature recognition compared to a priori mapping.
Finally, deep-sea missions can require continuous operation over thousands of kilometers without the aid of Global Positioning System (GPS) localization or human communication or cognition, imposing substantial autonomy requirements on an already complex system.
Currently, manipulation operations on the seabed are conducted by Remote Operated Vehicles (ROVs) tethered to a manned surface platform and tele-operated by a human pilot. Exclusive use of ROVs severely limits the potential utility of robots in the marine domain, as ROVs cannot extend beyond their tether length and require multiple operators to achieve mission objectives.
Wireless communications at the bandwidth necessary to reliably tele-operate an underwater robot is largely impractical due to the significant attenuation of electromagnetic wave propagation and available bandwidth in the acoustic spectrum.
To operate more effectively in these adverse underwater domains, DARPA is seeking proposals to develop a robotic system capable of long-distance, underwater manipulation missions. This robotic system, the “Angler”, will operate autonomously and without external communication, to navigate, search, localize, and physically manipulate objects on or near the seabed, using an onboard sensor suite to self-localize, avoid obstacles, manage interaction with the seabed environment, and fulfill manipulation mission objectives.
In addition to these navigation and positioning challenges, the robot will be able to perform these search and manipulation objectives autonomously, even in dark, turbulent, and semi-opaque sea conditions. Manipulation capability will be task-agnostic, allowing the onboard autonomy control module to identify optimal grasping, movement, and tool configurations to alter, place, or even recover underwater objects of interest.