Active Suspension Design Requirements for Compliant Boundary Condition Road Disturbances

The aim of suspension systems in vehicles is to provide the best balance between ride and handling depending on the operating conditions of a vehicle. Active suspensions are far more effective over a variety of different road conditions compared to passive suspension systems. This is because of their ability to store and dissipate energy at different rates. Additionally, they can even provide energy of their own into the rest of the system. This makes active suspension systems an important topic of research in suspension systems. The biggest benefit of having an active suspension system is to be able to provide energy into the system that can minimize the response of the sprung mass. This is done using actuators. Actuator design in vehicle suspension system is an important research topic and a lot of work has been done in the field but little work has been done to estimate the peak control force and bandwidth required to minimize the response of the sprung mass. These two are very important requirements for actuator design in active suspensions. The aim of this study is estimate the peak control force and bandwidth to minimize the acceleration of the sprung mass of a vehicle while it is moving on a compliant surface. This makes the road surface a bi-lateral boundary and hence, the total system is a combination of the vehicle and the compliant road. Generalized vehicle and compliant road models are created so that parameters can be easily changed for different types of vehicles and different road conditions. The peak control force is estimated using adaptive filtering. A least mean squares (LMS) algorithm is used in the process. A case study with fixed parameters is used to show the results of the estimation process. The results show the effectiveness of an adaptive LMS algorithm for such an application. The peak control force and the bandwidth that are obtained from this process can then be used in actuator design.