Hexapod load and range of motion analysis for expanding optomechanical applications at NASA Marshall’s X-ray & Cryogenic Facility

The Center of Curvature Optical Bench (CoCOB) hexapod, originally designed for James Webb Space Telescope program testing, was re-purposed to provide precision positioning of large test articles as part of a facility capability upgrade at the X-Ray & Cryogenic Facility (XRCF) at the NASA Marshall Space Flight Center. The analytical tools developed to assess and display the possible range of motion combinations for various center of rotation locations are discussed along with the results of the study. A hexapod load study was also completed to determine maximum allowable payload mass across a wide array of possible hexapod poses. Modeling was used to assess deflections as a function of the displacement away from the hexapod’s null position and the associated impact on accuracy performance. Software techniques to prevent collisions between internal hexapod geometry and avoid overtravel of both actuator stroke and end-joint angular travel ranges are also discussed.