A team of researchers led by New Mexico State University Civil Engineering Assistant Professor Qianyun (Gloria) Zhang is working with the New Mexico Department of Transportation on two research projects to use fast-developing digital robotic technologies to create a comprehensive robotic-enabled bridge inspection system.
“We are developing a comprehensive robotic-enabled bridge inspection system from data collection to data interpretation. The ultimate objective is to align robotic-enabled inspection with national standards, facilitating the integration of research into practical implementation to boost the bridge inspection practices in New Mexico,” Zhang said.
The Federal Highway Administration’s 2022 national bridge inventory reported there are 4,033 bridges in New Mexico, 4.9% of which are classified as structurally deficient and 38.9% in need of repairs at an estimated cost of $1.6 billion. Nationwide, the problem is much larger.
The efforts involved in the inspection and maintenance of bridges are challenged by a system lacking in sufficient availability of workforce, time and funding. It can also be dangerous to perform these tasks in traffic or from heights. Addressing these challenges, the team, which comprises Zhang and two Ph.D. students, is partnering with the University of New Mexico and New Mexico DOT District 2 for a two-phase, two-year project initiated in October.
The first phase comprises a pilot program which involves the use of unmanned aircraft systems and advanced image analysis techniques that can recognize objects more readily than other methods. This will entail the development of an advanced UAS platform and training of pilots followed by laboratory flight and field tests to evaluate and optimize the UAS platform. The second phase, to begin in fall of 2024, will be primarily focused on extensive data collection, database establishment, methodological exploration, and the development of implementation software.
While the National Bridge Inspection guidelines for condition rating inspection include safety data for a number of bridge components, this project will focus on the bridge deck, as this component is the most directly impacted by traffic loads. Accurate and current assessment of the bridge deck condition is critical for ensuring the safety and soundness of the entire bridge structure.
The research team hopes to show that UAS-based inspections provide a more efficient solution to field data acquisition. They hypothesize that these new automated methods will result in significantly reduced costs due to lower labor needs, shorter periods of traffic closures, and costs for hard-to-access locations which require scaffolding and cranes. They may also improve worker safety by reducing the need for inspectors to work at heights or in traffic situations. The use of automated objective data interpretation is expected to enable more frequent and timely bridge inspections.
One of the most important goals of this project involves technology transfer so that it may benefit the entire state of New Mexico transportation system. This will include a site demonstration, training of the developed UAS platform software for NMDOT personnel.
“NMDOT is currently grappling with a shortage of skilled staff, posing a challenge. The outcomes of this project will have a significant impact on improving the operational efficiency of bridge inspection. The technology transfer workshop will provide the opportunity to NMDOT personnel to undergo training in advanced technologies, facilitating their implementation across various districts,” Zhang said.
“Integrating drones into infrastructure inspection processes will catalyze rapid advancements in the inspection practices of the state of New Mexico. This initiative aims to address various concerns such as cost, efficiency and safety. In a long-term collaboration with Dr. Zhang, we are dedicated to crafting comprehensive UAV inspection systems that will significantly elevate the standards of bridge inspection practices,” said Jonathan Boyle, NMDOT District 2 Bridge supervisor.
Another year-long project addresses the challenges involved in underwater inspection. The study, which began in November, proposes to use underwater robots for substructure inspection.
To ensure public safety and protect overwater bridges, underwater structures must be inspected for structural integrity. In shallow water, such structures can be inspected from above. In relatively deep water, however, diving or other techniques are required. Underwater inspections require highly skilled inspectors as well as specialized equipment and documentation techniques.
“Even though we don’t have that much water, the demand for underwater inspection persists. Moreover, the shortage of proficient divers poses a challenge for conducting underwater inspections. The implementation of an advanced robot system provides a promising solution to perform low-cost and efficient underwater inspections,” Boyle said.
The team will compare remote-operated robotic systems and various high-resolution sensors and conduct prototype field demonstrations to assess performance. Advanced computer vision algorithms will be developed to perform automated data processing and interpretation that will be programmed into web-based software. The proposed system is expected to deliver rapid data collection, high-quality data, objective data interpretation, cost efficiency, lower safety concerns, lower labor cost and easy repeatability. The same system could also be applied to other underwater inspection applications, like dam inspections.
Zhang joined the Civil Engineering department at NMSU in August 2022, following her graduation from the University of Pittsburgh. She directs the Z-Lab, where she leads research for a team of three Ph.D. students and three M.S. students, each engaged in various projects. The goal of Z-Lab is to explore innovative solutions that can revolutionize and address existing challenges within the fields of civil engineering and general engineering.
Additionally, Zhang is co-director of NMSU’s Bridge Inspection Program which has a storied history spanning several decades. This program has a longstanding reputation for excellence at NMSU and has made substantial contributions to infrastructure maintenance as well as workforce development in the state of New Mexico.
