William R. Doggett

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—Many initiatives under study by both the space science and earth science communities require large space systems, i.e. with apertures > 15 m or dimensions > 20 m. This paper reviews the effort in NASA Langley Research Center's Automated Structural Assembly Laboratory which laid the foundations for robotic construction of these systems. In the Automated(More)
We describe an Intelligent Precision Jigging Robot (IPJR), which allows high precision assembly of commodity parts with low-precision bonding. We present preliminary experiments in 2D that are motivated by the problem of assembling a space telescope optical bench on orbit using inexpensive, stock hardware and low-precision welding. An IPJR is a robot that(More)
A visualization system is being developed out of the need to monitor, interpret, and make decisions based on the information from several thousand sensors during experimental testing to facilitate development and validation of structural health monitoring algorithms. As an added benefit the system will enable complete real-time sensor assessment of complex(More)
The use of tradeinarks or names of manufacturers in this report is for accurate reporting and does not constitute an official endorscment, either expressed or implied, of such products or manufacturers by the National Aeronautics and Space Administration. Abstract Concern over limited extravehicular and intravehicular activitiy time has increased the(More)
The center of mass space is a convenient space for planning motions that minimize reaction forces at the manipulator's base or optimize the stability of a mechanism. A unique problem associated with path planning in the center of mass space is the potential existence of multiple center of mass images for a single Cartesian obstacle, since a single center of(More)
—This paper provides closed-form equations parame-terizing the 2 smooth path that globally minimizes the Euclidean norm of a robot's peak base reaction force while avoiding obstacles during three-dimensional maneuvers in a gravity-free environment. In addition, the paper describes a computationally efficient technique that leads to a path typically having a(More)
A comprehensive modular assembly system model has been proposed that extends the art from modular hardware, to include in-space assembly, servicing and repair and it's critical components of infrastructure, agents and assembly operations. Benefits of modular assembly have been identified and a set of metrics defined that extends the art beyond the(More)
This paper describes an Intelligent Precision Jigging Robot (IPJR) prototype that enables the precise alignment and welding of titanium space telescope optical benches. The IPJR, equipped with μm accuracy sensors and actuators, worked in tandem with a lower precision remote controlled manipulator. The combined system assembled and welded a 2 m truss(More)
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