Researchers from the University of Manchester have developed a breakthrough system for underwater robot positioning in confined spaces, addressing a long-standing challenge in marine robotics. The team, led by Dr. Xueliang Cheng and Professor Barry Lennox, has created the Collaborative Aquatic Positioning (CAP) system, which integrates collaborative robotics and sensor fusion to enable precise localization in environments where traditional methods fail.
The problem of underwater robot positioning has plagued the industry for years. Existing systems, designed primarily for open-water environments, struggle in industrial settings due to poor coverage, reliance on external infrastructure, and the need for feature-rich surroundings. Multipath effects from continuous sound reflections further degrade signal quality, reducing accuracy and reliability. This technological bottleneck has limited the deployment of underwater robots in critical applications such as inspection, maintenance, and repair of submerged infrastructure.
The CAP system overcomes these limitations by leveraging a “mother-ship” concept, where a surface vehicle acts as a mobile leader to assist in positioning a submerged robot. This approach enables localization even in GPS-denied and highly constrained environments, eliminating the need for fixed infrastructure, extensive calibration, or environmental features. The system combines advances in mobile robot sensing and leader-follower control to deliver accurate, practical, and infrastructure-free underwater localization.
The researchers validated the CAP system in a large test tank, conducting repeatable autonomous missions using CAP’s position estimates for real-time trajectory control. The experimental results demonstrated a mean Euclidean distance (MED) error of just 70 mm, achieved in real time. This level of accuracy is a significant improvement over existing methods and opens up new possibilities for underwater robotics in confined spaces.
The practical applications of the CAP system are vast. In the marine sector, it could revolutionize the inspection and maintenance of offshore structures, underwater pipelines, and other submerged infrastructure. The ability to deploy underwater robots in confined spaces with high accuracy and reliability could also enhance search and rescue operations, environmental monitoring, and scientific research. Furthermore, the CAP system’s infrastructure-free design makes it highly adaptable to various environments, from industrial settings to natural underwater landscapes.
The development of the CAP system represents a significant step forward in underwater robotics. By addressing the technological bottleneck of positioning in confined spaces, the researchers have unlocked new potential for autonomous missions in the marine sector. As the technology continues to evolve, it is likely to play a crucial role in advancing the capabilities of underwater robots and expanding their applications in various industries. Read the original research paper here.