Yizhi Liu, assistant professor in the Department of Civil and Environmental Engineering (CEE), has been awarded a grant from the National Science Foundation (NSF) to design an AI-enabled robot that can conduct safe, efficient roof inspections.

A hybrid drone that can land on and navigate around a building roof, the robot is designed to switch seamlessly between flight mode and legged mode. This technology allows for safe and detailed roof inspections, an often hazardous construction task that can lead to falls, injuries, and even fatalities.

“As part of this project, we’re developing a new aerial-legged robot that can both fly and walk,” says Liu. “The idea is that the robot can take off like a drone, land on a roof and then switch into legged mode to carefully navigate around obstacles. By combining multiple sensing technologies – cameras for vision, LiDAR for mapping and tactile feedback for surface contact – the robot can build a rich understanding of its environment and make intelligent decisions in real time.”

Liu, an expert in construction robotics and human-robot interaction, joined the College of Engineering and Computer Science (ECS) in 2024 after completing a Ph.D. in architectural engineering at the Pennsylvania State University. He also holds master’s degrees in electrical engineering, robotics and civil engineering.

“Roof inspections are one of the riskiest jobs in construction, and our aim is to reduce the hazards workers face while also making the process faster and more accurate,” Liu says. “Instead of having a person climb onto a roof, the robot can do the job autonomously and provide detailed inspection data.”

“We’re also partnering with construction companies to test the robot in actual worksites, which will give us valuable feedback on how it performs outside the lab. Beyond the technical side, we’re planning workshops and outreach programs to introduce students to AI and robotics in civil engineering. We hope this project inspires the next generation of engineers to see how advanced technologies can make construction both safer and smarter.”

“Dr. Liu’s research exemplifies our department’s commitment to both rigorous scholarship and practical application,” says CEE Department Chair Andria Costello Staniec. “This project not only advances our understanding of AI technologies, it also delivers real-world impact that will protect workers and has the potential to transform construction industry safety practices.”

This collaborative three-year grant was awarded through NSF’s Foundational Research in Robotics program. Liu will serve as principal investigator, working with collaborators from the University of Illinois Urbana-Champaign, as well as ECS mechanical and aerospace engineering professors Amit Sanyal and Zhenyu Gan, who will serve as co-principal investigators.