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Agnes, Gregory

Publications and source records attributed to Agnes, Gregory.

A Robotically Assembled and Serviced Science Station for Earth Observations

In this paper we present the overall architecture of a ”Science Station”, a robotically assembled and serviced persistent platform that can host multiple payloads for Earth observations. Recent decadal survey findings motivate the need to have spatial and temporal concurrency in measurements from multiple instruments. We have architected the science station to simultaneously host up to twelve Earth Venture class instruments at a time. These instruments can be replaced by newer instruments periodically to take advantage of evolving science needs and technology capabilities. The Science Station can also concurrently host science, commercial, defense and other national interest payloads. The Science Station may provide a cost-effective paradigm by mitigating some of the risks and costs associated with multiple free-flyers that may otherwise be needed for the various instruments. It leverages emergent and existent technologies in robotic assembly and servicing, lower cost commercial launch vehicles, secondary launch vehicles, and rendezvous and proximity operations. In this paper, we report the findings of a survey we conducted on the desired performance of the Science Station from various instrument hosting perspectives. We report the various trade studies that we conducted to developed a feasible architecture that meets the goals of the Science Station while also meeting the constraints of a space system. We also report the various considerations in the configuration, thermal system, pointing system, overall concept of operations, and the robotic system of the Science Station architecture. The paper then describes a testbed activity we are undertaking to evaluate the supervised autonomy robotics needed for the Science Station as well as to conduct a riskreduction demonstration of the end-to-end robotics behaviors.

Mukherjee, Rudranarayan

Systems and Methods for Implementing Bulk Metallic Glass-Based Macroscale Compliant Mechanisms

Systems and methods in accordance with embodiments of the invention implement bulk metallic glass-based macroscale compliant mechanisms. In one embodiment, a bulk metallic glass-based macroscale compliant mechanism includes: a flexible member that is strained during the normal operation of the compliant mechanism; where the flexible member has a thickness of 0.5 mm; where the flexible member comprises a bulk metallic glass-based material; and where the bulk metallic glass-based material can survive a fatigue test that includes 1000 cycles under a bending loading mode at an applied stress to ultimate strength ratio of 0.25.

Hofmann, Douglas C.