Isolation Platform for Long Range Optical Communications

Optical communication links provide higher data transfer rates with lower mass, power, and volume than conventional radio-frequency links. For deep space applications at long operational ranges, high performance stabilization of the space terminal data link is required. To meet this need, CDI has developed a novel application of our free-floating isolation platform. Based upon a Shuttle-proven technology, this approach yields 6-DOF isolation from the disturbances of the host vehicle while providing high-bandwidth active stabilization to attenuate both payload disturbances as well as any residual disturbances transferred from the base across the power/data umbilical. The proposed approach is designed to achieve better than 0.5microradian-rms stabilization for all frequencies above 0.1Hz when operating on a spacecraft. Phase I developed the design concept, demonstrated robustness through sensitivity studies, demonstrated performance through simulation, and establish the feasibility of the approach to meet the space terminal isolation requirements. Component testing of the sensors and actuators further demonstrated that the design will meet the performance requirements. These tests and analyses advanced the technology to TRL-4. Phase II continues the development by ground testing an end-to-end prototype on a soft suspension testbed to demonstrate overall performance in a simulated low-g operational environment. Both acquisition search and beacon track will be demonstrated. Iterations of development and environment testing are performed to produce several space qualified 2-axis strut assemblies for delivery to NASA. Three strut assemblies rigidly mounted to any space terminal will provide 6-DOF isolation and high-bandwidth stabilization. These struts are designed for robustness so they can be used as an add-on to any rigid structure, thus enabling a broad range of space applications that require high-precision stabilization, isolation, and pointing.