Soft stewart platform for robotic in-space assembly applications

Research into controlling how robotic manipulation of materials can impart stresses into the system is a novel realm. Great robustness is needed to handle a variety of autonomous behaviors for the uncertainty of reaction from materials of different properties ranging from lightweight gossamer to stiffer truss structures. Currently robotic manipulation for space applications is done on a very case by case basis but in-space assembly (ISA) and servicing applications introduce a large number of possible uncertainties and anomalies that would be a departure from regular operations. My mechatronics thesis project focused on the development a Soft Stewart Platform (SSP) robot with precise 6 Degrees of Freedom (DOF) position control. A platform such as this could provide high precision with compliance to handle a diversity of material strengths, from stiff heterogenous structures to soft goods. The SSP concept is comprised of six Soft Linear Actuators (SLAs) with precision length control. An additional benefit of a SSP versus the conventional hard Stewart platform is the ability to store the robot in a compact state that is shorter than half the full actuator length, the limit for conventional electric linear actuators. The main application selected for this SSP concept was as an end effector to robotically manipulate gossamer structures and mitigate the impartment of stress and conduct specified testing on space telescope sunshields for how this manipulation could benefit deployment and handle servicing of anomaly cases. Overall, my research would provide benefits to NASA missions such as deploying, or recovering from failed deployment, of space telescope sunshields critical for astrophysics science such as exoplanet observations. The report will also provide a history of ISA, the current space telescope paradigm, and plans for the in-space construction of large telescopes. Bringing forth the recent advancements in robotic ISA ground demonstrations shows a promising ability to shift to a new robotic ISA paradigm to mitigate risk and enrich science over a longer lifetime of a space telescope therefore getting more value for the initial upfront cost of the mission.--Author's abstract