Ci-Jyun (Polar) Liang's research interests include human-robot collaboration, computer vision, reinforcement learning, building information modeling (BIM), digital twins, and extended reality to promote sustainability and safety in future robotized workplaces such as construction sites, manufacturing plants, and warehouses. His current research involves (1) developing a computer vision and sensor fusion system for identifying safety hazards in human-robot collaboration, (2) developing collaborative robots, extended reality, and imitation learning algorithms for sustainable construction and built environments, (3) investigating reinforcement learning methods, BIM, and digital twins for closing sim-to-real gaps in unstructured construction environments.