The influence of platform mass properties on simulator motion system performance

Introd uctlon The dynamic performance of a simulator motion system is to a great extent determined by the mechanical qualities of the motion system hydraulics, the motion control system which provides signals to drive the actuator servo valves, and also the mass properties of the moving equipment of the simulator placed upon the motion system. Quite commonly, in the case of training flight simulators, the centre of gravity of the large moving payload is located far above the motion system's upper gimbals. An investigation, using a complete dynamic model of the hydraulic motion system, was carried out to quantify the effects of payload mass properties on motion system performance. This paper will review the results obtained from these studies. It is found that the total mass and the vertical location of the centre of gravity influence the time delays, phase and parasitic noises of the motion system, and that these properties also limit i n y further improvements due to design changes in software or hydraulic hardware. By adapting these design considerations, a motion system with inherently higher performance will result. Therefore, a fundamentally new and yet practical light-weight motion platform design is proposed. This configuration is being introduced in the multi-functional SIMONA Research Simulator of the Delft University of Technology. Assistant Professor, SIMONA Project Leader Member AlAA