Velocity and location information from onboard vibration measurements of rail vehicles

Vehicles in motion are exposed to mechanical vibrations, resulting from various sources, such as the engine, transmission, wheels, the track and many more. Vibrations in vehicles are often undesired, but these vibrations contain navigation and vehicle information. In addition to state-of-the-art techniques for the computation of spatial vehicle movements from inertial measurements, the vibration measurements can also be used explicitly for navigation with appropriate methodologies. This first study focuses on vibrations in a diesel engined passenger train, measured by a vertical, translative acceleration sensor. The major vibration sources of a train in motion are identified in an analysis and characterized by speed dependency or independency. We present procedures to separate and filter these vibrations in combination with a simple model of the vehicle. This paper presents new methods to infer vehicle speed and the wheel diameter measurements for a wheel diagnostic monitoring during motion. Furthermore a rail vehicle localization is achieved based exclusively on vibrations measured by one accelerometer and a correlation technique. We show promising track-selective train localization results by the location dependent vibrations, discuss improvements and an integration in a multi sensor localization approach as well as the advantages and drawbacks of vibration based navigation.