|12. Measuring Method of Pantograph Contact Force|
There are several shapes and mechanisms of pantograph on Shinkansen and conventional lines, and a method to measure contact force for most forms of pantograph has been developed. The contact force is determined from the force arising on a certain section of the pantograph (i.e. the section force), inertial force, and aerodynamic force. The section force can be obtained from the strain on the pantograph head or on the pan spring, while the inertial force can be obtained from multiple accelerometers attached to the pantograph head (Fig. 1) and equivalent masses of that. The method to obtain inertial force using an accelerometer is already widely used in Europe, and the measuring frequency of that method by an accelerometer is up to about 20 Hz, while the newly developed method by multiple accelerometers can measure up to 40 - 50 Hz (and up to 100 Hz for some types), enabling highly precise measurement.