A Lightweight Robotic Device Based on a Micro-Macro Actuation Concept for the Inspection of Railway Pantograph

Functional verification of railway pantographs is performed within periodic maintenance programs by means of specifically designed automation and robotic devices that can check their structural integrity and correct functionality. In this paper, we present the design and validation of a new portable inspection robotic device that through structural dynamic excitation and passive movement can assess the health status of railway pantographs. The device is endowed with a new actuation system that combines the large range of force attained through a macro-Actuator with the high-frequency capabilities of a micro-Actuator while preserving lightweight structure. The reported design and experiments confirm that excitation transmission by accurate force control can be achieved in the entire frequency range, despite the interaction between actuator and structure, and that simulated defects can be revealed by low and high-frequency alterations.