New cable-laying system
Offshore electricity generation is becoming increasingly important for Europe. However, conventional techniques lay unprotected cables directly on the seabed, where they are subject to damage. The EU-funded HEXATERRA (The development of a modular 'stepping locomotion' system for installation on subsea trenching machines used for subsea energy cable burial) project developed the necessary technologies. The innovations involve a modular stepping locomotion system for traversing the undersea terrain, which also digs trenches and lays cable. During the project, the team developed the legged-locomotion hardware. The equipment was able to step in all directions, remained stable despite disturbance and accurately manoeuvred as intended. Locomotion control firmware and hardware achieved precise and stable positioning, and waves and currents had no effect. Researchers also developed visual and haptic user interfaces. The interfaces combined key data from several sensor systems, providing a detailed image and reference frame. The sensor array utilised a Kalman filter, thus overcoming conventional sensor limitations. HEXATERRA's new cabling machine avoids damage to cables from the marine environment, while maximising the reliability of renewable power networks. Hence, the innovations also help minimise impact on the ocean.
Keywords
Undersea cables, sensor system, HEXATERRA, stepping locomotion, subsea, trenching
