MECHANICAL LOADS IDENTIFICATION AND DIAGNOSTICS IN LAND VEHICLE SUSPENSIONS THROUGH INTEGRATED SENSING AND FORCE STATE MAPPING

摘要

Commercial and defense vehicle systems operate in highly variable loading environments. Variability in static and dynamic loading can cause damage to components and lead to excessive warranty costs and overly aggressive maintenance schedules. Manufacturers are utilizing data interrogation methodologies for identifying loads and damage in suspensions, tires and other vehicle components to reduce the total cost of vehicle ownership. The application of loads and damage identification techniques for mechanical vehicle systems is discussed here. Operating, passive response data from suspension systems in passenger cars are examined. Mechanical damage in these components, i.e., degradation to shock, is identified experimentally using force state maps and transmissibility functions, which are generated using acceleration data in conjunction with fundamental mechanics models. The force state maps also provide the suspension restoring force estimates, which must be used to prognosticate remaining life and predict trends in the damage indices. Diagnostic challenges associated with nonlinear operational characteristics of these components and their sensitivity to loading levels and spectra are also discussed.