The Development of a Mechanical Friction Measurement Approach to Employ a Novel Designed and Manufactured Pantograph Tribometer

Abstract

Light rail systems are a critical transport technology with advantages such as environmental sensitivity, transport comfort, a solution to public transport, which has become a problem in big cities, and developing technology. Electric power from the transformer must be sent to the train's power units to facilitate movement in rail systems, ensuring uninterrupted supply along the route. In rail systems, this function is performed by the contact of two components: the current collector carbon strip on the pantograph and the copper catenary contact wire. This study involves a new design and fabrication of a programmable and measurable tribometer device that simulates the sliding frictional wear between the current collector carbon strip plate and the catenary contact wire, a component of the pantograph mechanism in rail systems. A strain gauge-based dynamometer was integrated into the device to measure the contact force (Fc), radial force (Fr), and axial force (Fa) generated on the surface during the interaction between carbon strip and copper wire. The dynamometer was manufactured and calibrated by accounting for the tribometer design's operational mechanics, and the measured forces' cross-interactions were eliminated. Thanks to the built control and analysis software, three different tests were conducted at three different speed settings (15, 20, and 25 km/h), contact force ranges (30-35 N, 50-55 N, and 40-45 N), and distances (10, 15, and 20 km). The measured average friction coefficients were 0.79, 0.77, and 0.76, while the corresponding wear rates of the carbon strip were calculated as 0.014, 0.0267, and 0.0175 g/km, respectively. The tribometer demonstrated reliable performance with a deviation of 2.5% between repeated experiments. The experiments demonstrated that the constructed tribometer could effectively simulate the mechanical friction and wear interaction between the carbon strip and copper contact wire, providing stable outcomes.