Optimization of Six-Degrees-of-Freedom Motion Systems for Flight Simulators

The cueing capabilities of a synergistic e ight-simulator motion system are limited primarily by the maximum translationaland rotational travelallowed by themotion-base.Thistravelcapability,also known astheworkspace, is dictated by the kinematic layout of the motion system. Furthermore, the Jacobian matrix, which maps velocities from platform space to joint space, indicates the dexterity of the mechanism, or the mechanical effort needed by theactuatorsto movetheplatform. To systematically design unconventionalmotion-bases, a methodology hasbeen developed to analyze arbitrary six-degrees-of-freedom motion systems. The approach is based on an optimization programtodeterminetheoptimallayoutofthemotionsystem,giventheworkspaceperformanceobjectivesandthe design constraints. This allows the investigation of unconventional platform geometries and actuator attachment points, thus allowing the designer to tailor the workspace as required by the simulation task, to ensure that a satisfactory dexterity is maintained, and to guarantee that the actuator legs do not interfere mechanically. This paper describes the proposed methodology, and shows examples of its applications, e rst to generic workspaces, and then to the workspace required for the simulation of a large transport aircraft.