Rotterdam-based DroneQ Robotics deployed SEAMOR Marine’s advanced Chinook ROV in the Port of Maassluis to assess the condition of a bridge’s underwater foundation.
Photo credit: John Troch, DroneQ Robotics
This inspection was part of the expansion of Rotterdam’s metro system, specifically the Hoekse Lijn, which took over a 24-kilometer stretch of existing railway between Rotterdam and Hook of Holland.
The public transport company (RET) needed to evaluate the infrastructure, including a busy section with a bridge, where the underwater portion had not been inspected for over 130 years. The goal was to determine if the bridge’s foundation met NEN 2767 compliance standards.
Problem
Navigating the ROV was challenging due to the shallow depth of only 5 meters and the rapidly changing currents within 2.5 meters of the surface.
The water was murky, filled with harbor debris, and blurred by the mix of fresh and saltwater from the nearby river flowing into the ocean. Despite these difficulties, precise navigation was crucial to avoid disturbing the sediment on the seabed.
Solution
The Chinook ROV had to maintain a lateral flight path while consistently keeping a 10 cm distance from the bridge and remaining at a 90-degree angle.It also inspected beneath the bridge foundation, which had a height of only 80 cm, requiring the ROV to maneuver with just 10 cm of clearance above and below.
DroneQ employed a concrete and wood integrity measurement device, developed in collaboration with Saxion University, to measure the thickness of the bridge foundation.
Photo credit: John Troch, DroneQ Robotics
Results
The Chinook ROV successfully navigated the tight spaces to reach and assess the bridge’s foundation. With the ROV’s manual and auto-focus HD camera, it captured high-quality images that were crucial for the final report provided to the public transit company.
No critical defects were found, and the bridge was in remarkably good condition. The high-definition images not only documented the condition of the aging bridge but also supported the development of a long-term maintenance plan and helped in determining budget allocations for ongoing upkeep.
John Troch, Director and Co-founder of DroneQ Robotics in Rotterdam, commented, “The quality of the Chinook’s HD camera used in this ROV inspection never ceases to amaze me in the murky waters of the Port of Maassluis in the Netherlands.
“The engineering company doing the final reporting for the public transit authority was also stunned by the quality of the images. What we like most about the Chinook is the modular setup, where in the field we can change/repair it quite easily, thus improving project business continuity.”
