Mechanical Components

Robot Forearm and Dexterous Hand

The hand is highly anthropomorphic and even includes a folding palm. An electromechanical hand-and-forearm assembly has been developed for incorporation into an anthropomorphic robot that would be used in outer space. The assembly is designed to offer manual dexterity comparable to that of a hand inside an astronaut’s suit; thus, the assembly may also be useful as a prosthesis or as an end effector on an industrial robot.

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Synthetic Bursae for Robots

Functions would be similar to those of natural bursae. Synthetic bursae are under development for incorporation into robot joints that are actuated by motor-driven cables in a manner similar to that of arthropod joints actuated by muscle-driven tendons. Like natural bursae, the synthetic bursae would serve as cushions and friction reducers.

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Software for Secondary-School Learning About Robotics

The ROVer Ranch is an interactive computer program designed to help secondary-school students learn about space-program robotics and related basic scientific concepts by involving the students in simplified design and programming tasks that exercise skills in mathematics and science.

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Thermally Insulating, Kinematic Tensioned-Fiber Suspension

Tensioned polymer fibers afford both rigidity and high thermal resistance. Figure 1 shows a salt pill and some parts of a thermally insulating, kinematic suspension system that holds the salt pill rigidly in an adiabatic demagnetization refrigerator (ADR). “Salt pill” in this context denotes a unit comprising a cylindrical container, a matrix of gold wires in the container, and a cylinder of ferric ammonium alum (a paramagnetic salt) that has been deposited on the wires. The structural members used in this system for both thermal insulation and positioning are aromatic polyamide fibers (Kevlar® or equivalent) under tension.

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Back Actuators for Segmented Mirrors and Other Applications

Actuation mechanisms could be simpler. Back actuators have been proposed as alternatives to edge actuators considered previously for use in aligning hexagonal segments of lightweight segmented astronomical mirrors planned for use in outer space. The proposed back actuators could also be useful on Earth as parts of wafer-conveyance systems in the semiconductor industry.

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Mechanism for Self-Reacted Friction Stir Welding

This mechanism performs better than others that have been tried. A mechanism has been designed to apply the loads (the stirring and the resection forces and torques) in self-reacted friction stir welding. This mechanism differs somewhat from mechanisms used in conventional friction stir welding, as described below.

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Simple Systems for Detecting Spacecraft Meteoroid Punctures

A report describes proposed systems to be installed in spacecraft to detect punctures by impinging meteoroids or debris. Relative to other systems that have been used for this purpose, the proposed systems would be simpler and more adaptable, and would demand less of astronauts' attention and of spacecraft power and computing resources. The proposed systems would include a thin, hollow, hermetically sealed panel containing an inert fluid at a pressure above the spacecraft cabin pressure. A transducer would monitor the pressure in the panel. It is assumed that an impinging object that punctures the cabin at the location of the panel would also puncture the panel. Because the volume of the panel would be much smaller than that of the cabin, the panel would lose its elevated pressure much faster than the cabin would lose its lower pressure. The transducer would convert the rapid pressure drop to an electrical signal that could trigger an alarm. Hence, the system would provide an immediate indication of the approximate location of a small impact leak, possibly in time to take corrective action before a large loss of cabin pressure could occur.

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