Adaptive Williams Filters for Active Vehicle SuspensionsB

With active vehicle suspension, one can tailor a vehicle's response to load and inertial disturbances without affecting the vehicle response to road disturbances. This decoupling is achieved in (Williams and Best 1994) and (Smith and Wang 2002) using a filtered combination of measured signals. These filters, which we call Williams filters, require exact knowledge of certain vehicle parameters including vehicle mass to achieve the desired decoupling. However, vehicle parameters, such as mass, are subject to abrupt variations as vehicle load changes. Here we propose an adaptive Williams filter that does not require knowledge of vehicle parameters.