Development and Demonstration of a Non-hydraulic Actuator for Application in Active and/or Semi-active Suspension Systems

A program for the preliminary design, prototype construction, and bench testing of a linear pneumatic suspension strut for application in non-hydraulic combat vehicle suspension systems is presented. The proposed suspension strut system components include an air spring, accumulator, and variable size orifices for the active control of strut dynamic performance. Strut natural frequency, damping ratio, and strut extension are independently adjustable parameters over a specified range of values through controlled sizing of the system airflow orifices and an air source. An optimal control study using a classical Calculus of Variations (Mayer formulation) approach is proposed to determine the feasibility of the strut in an active control system for a quarter vehicle model. System objective functions under consideration include various combinations of vehicle ride quality and controllability. The proposed effort includes a detailed design of the linear suspension strut and bench testing to verify strut natural frequency and damping ratio ranges.