Multi-Platform Inspection Maintenance & Repair In Extreme Environment (MIMRee)

Offshore wind turbine blades operate in demanding environments, where exposure to extreme weather and continuous use can lead to surface damage and structural deterioration. Inspection and repair have traditionally relied on highly skilled technicians working at height, subject to limited weather windows and significant safety risks.

MIMRee explored how coordinated teams of autonomous and remotely operated robots could provide a safer, more efficient alternative.

The project investigated a multi-robot system combining autonomous surface vessels, aerial drones and blade-crawling robots.

The proposed system would enable initial blade inspection while turbines remained operational, followed by closer investigation and repair on stationary blades using robots deployed by drones.

RCA Robotics Laboratory's contribution focused on developing a lightweight, multifunctional robotic repair arm capable of performing essential blade maintenance tasks.

The arm incorporated an automatic tool-changing mechanism for cleaning, sanding, filler application and surface finishing. A bespoke user interface enabled remote operation, visual feedback and human intervention, combining robotic autonomy with human expertise.

By the project's conclusion in July 2021, the consortium had demonstrated core technologies underpinning coordinated robotic maintenance, with individual systems evaluated through experimental testing, simulation and field demonstrations.

The RCA team developed and experimentally validated a modular repair arm weighing approximately 1.8 kg, achieving tool changes within eight seconds and a maximum end-effector positioning error of 3 mm. The design was approximately 84% lighter than comparable technologies considered in the published research.

These findings demonstrated the feasibility of lightweight, adaptable robotic tools for remote infrastructure repair and contributed to research into autonomous maintenance of offshore renewable energy systems.

MIMRee established a proof of concept for robotic collaboration in demanding offshore environments, demonstrating technologies that could support future remotely supervised inspection and maintenance.

Beyond offshore wind energy, the project's approaches to modular repair, human–robot interaction and coordinated robotic systems offer potential applications in other environments where physical access is difficult, costly or hazardous.

The RCA research also contributed to understanding how robotic systems can extend human capabilities while reducing exposure to dangerous working conditions.

• 2024: Sadeghian, R. and Sareh, S., Robotic repair system, Publication No. WO2022079451, WIPO. https://patents.google.com/patent/US20240018942A1/en
• 2021: Sadeghian, R., and Sareh, S. Multifunctional Arm for Telerobotic Wind Turbine Blade Repair, 2021 IEEE  International Conference on Robotics and Automation (ICRA), May 30 - June 5, 2021, Xi'an, China.
• 2020: Bernardini, S., Jovan, F., Jiang, Z., Watson, S., Weightman, A., Moradi, P., Richardson, T., Sadeghian, R. and Sareh, S., 2020, Book Section, A multi-robot platform for the autonomous operation and maintenance of offshore wind farms AAMAS '20: Proceedings of the 19th Int’l Conference on Autonomous Agents and MultiAgent Systems. International Foundation for Autonomous Agents and Multiagent Systems, South Carolina, US, pp. 1696-1700.