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This report focuses on the mission engineering process for a hybrid force in 2025. Updated tasking from OPNAV N9I emphasized the necessity of focusing on the benefits of using cost-conservative unmanned systems. Specifically, the focus was placed on the near-peer competitor China and the problems that could be expected in an anti-access/area denial (A2/AD) situation in the South China Sea. The Naval Surface Warfare Center mission engineering approach was used to identify specific vignettes for proposed alternative fleet architectures and then analyzed using combat simulation and optimization models. Research on performance characteristics and cost were compiled on current unmanned systems, specifically those in development at a high technology readiness level. Proposed unmanned systems architectures were developed as solutions to the A2/AD problem and proposed vignettes. The unmanned systems architectures were then run through an optimization model to maximize system performance while minimizing cost. The results of the architecture optimization were then input into modeling and simulation. The overall effectiveness of each architecture in each vignette were then compared to find the most effective solution. An analysis of the results was performed to show the expected mission effectiveness and proposed cost of utilizing the proposed solution unmanned architectures. The most effective architectures included search, counter swarm, delivery, and attack systems. Lieutenant, United States Navy Lieutenant, United States Navy Lieutenant, United States Navy Major, Republic of Singapore Navy Major, Singapore Army Lieutenant, United States Navy Lieutenant, United States Navy Lieutenant, United States Navy Commander, United States Navy Approved for public release. Distribution is unlimited.

When completed in 1961, the roof of St. Charles Church became the largest unbalanced hyperbolic paraboloid structure in the world and the only shell structure in Spokane, WA. Situated on an 8-acre site on the north side of the city, St. Charles is a modernist structure designed through partnership of Funk, Molander & Johnson and architect William C. James. This asymmetric structure is over 45.72m (150ft) and utilizes folded edge beams that taper from 1067mm (42in) at the base to a 76.2mm (3in) thickness at the topmost edge using regular strength reinforcing steel and concrete. The novelty of the shell structure serves both architectural and structural design criteria by delivering a large, uninterrupted interior sanctuary space in materially and economically efficient manner. Having previously completed an initial analysis of the structure, now, 60 years later, a complete structural forensic evaluation of the shell has been conducted using full point cloud laser scanning to generate a complete in-situ model. The in-situ geometry and historic loads are described and deflections as first steps in a full structural forensic study. Results of the current in-situ geometry are compared to the design geometry of original construction documents.

This paper presents a tendon-driven robotic finger with its inspiration derived from the human extensor mechanism. The analytical model presented relates the contractions of the intrinsic muscles of the human hand to abduction-adduction and coordinated motion of proximal and distal interphalangeal joints. The design presented is simplified from the complex webs of fibers appearing in prior works, but preserves the dual role the interossei have of abducting/adducting the finger and flexing it at the metacarpal-phalangeal joint with the finger outstretched. The anatomical feature in our design is that the proximal interphalangeal joint passes through a set of lateral bands as the finger flexes. We discovered that by including a mechanical stop that causes the lateral bands to 'fold' at large enough flexion aids coordinated movements of the two interphalangeal joints as the finger flexes. Because it involves engineering running and sliding fits, this finger admits a concise kinematic model, which accurately predicts the tendon excursions from a known pose. In this work, however, we evaluate what happens when the model is used to search for a sequence of tendon excursions corresponding to a desired movement. We perform several such sequences of tendon excursions experimentally and present the poses that result using motion capture. We also demonstrate executing several types of grasps on an underactuated robotic hand that incorporates this finger design.