A Review on Automatic Visual Inspection for Railway Overhead Contact Line Systems

Inspections of overhead catenary systems include checks on the geometry of contact wire, the interaction between contact wire and pantograph, defects in components, worn components, and clearance are necessary to ensure the reliability, availability, maintainability, and safety of railways infrastructure and operation. An automatic visual inspection technology of overhead catenary systems can improve conventional inspection methods' efficiency, cost-effectiveness, and precision. This paper provides an overview and contributions of the research made by scholars in this field, as well as the application and advancement of automated visual inspection technology for railway overhead catenary systems. The projection of the future research direction for automatic inspection in overhead catenary system inspection activities was also provided.