Vibration isolation and suppression applied to mechanical servo-systems

Project members: M.I. Parra Calvache, P. Valk, O.H. Bosgra

Sponsored by: International Research Institute for Simulation, Motion and Navigation

The SIMONA Research simulator is a lightweight re-configurable cockpit mounted over a 6-DOF motion platform. It is desired that this simulator work with a wide bandwidth, from 10Hz to 15Hz, that would allow the simulation of special conditions. The requirements of higher speed and acceleration, and the desired high performance forced the use of lighter structures that have as drawback higher flexibility and more susceptibility to unwanted vibrations. Within this framework, it is our main interest to compensate for bending and vibrations over the components of the video display system, namely the projectors, the back projection screen and the mirror and to allow the high performance use of the motion hydraulic system for the simulation of special conditions. As a first approach, it is important to analyze the interaction between Video Display System components and how their performance is affected by the reference motion necessary to give the pilot the impression of real flight. This clearly involves knowledge over the flexible-multi-body cockpit structure and video display system. For this end, we will use experimental modelling tools giving emphasis to identification of multivariable systems in closed-loop and modal identification for mode shape representation. Further, we want to suppress unwanted vibration that deteriorates not only the performance but eventually the structural integrity of mirror or screen. As a first approach input shaping algorithms will be studied as passive damping technique keeping open possibilities of extra feedback (signals related to the performance of the Video Display System) aiming to a final active control of vibration of the cockpit structure.

Figure 21: Diagram of the SIMONA Research Simulator visual display system