This paper presents a Hardware-in-the-Loop (HIL) test setup used for studying the dynamics of an elastomer supported machine bed. The setup uses real elastomer dampers and modeled machine dynamics (process model) connected together via real-time interface. The HIL approach was chosen since the elastomers are a critical part of the system, however, determining their properties for engineering needs can be a challenging task. Accurate elastomer models include many parameters that can only be determined by experimentally, and even then their implementation for real-life applications is not always practical.
Using real elastomers supports in the simulation removes uncertainties associated with classic elastomer models, while simulated process makes it possible to test different scenarios fast and with good repeatability. The process model includes a description of the machine body, a rotating unbalanced drive mechanism creating cyclic loading and external excitation forces acting on the machine. The method enables testing of machine bed supports in a realistic operating environment.
A test rig was built for housing the elastomers incorporating a hydraulic actuator for producing the process movement. The hydraulic circuit was designed for good dynamic performance with predictive control to minimize delays in the real-time interface. It was found that the HIL-setup can provide fast and accurate information about the plant model behavior in different operating scenarios using the elastomer supports.