Engineering topics

Collins, Earl R., Jr.

Publications and source records attributed to Collins, Earl R., Jr..

At least 19 records

NASA NTRS1992

Electrorepulsive actuator

The invention is a linear actuator that operates under the principle that like charges repel and opposite charges attract. The linear actuator consists of first and second pairs of spaced opposed conductors where one member of each pair of conductors is attached to a fixed member, and where the other member of each pair of conductors is attached to a movable member such as an elongated rod. The two pairs of spaced conductors may be provided in the form of two spacedly interwound helical vanes where the conductors are located on the opposite sides of the two helical vanes. One helical vane extends inwardly from a housing and the other helical vane extends outwardly from an elongated rod. The elongated rod may be caused to move linearly with respect to the housing by applying appropriate charges of like or opposite polarity to the electrical conductors on the helical vanes.

Collins, Earl R., Jr.↗

NASA NTRS1991

Casting Of Multilayer Ceramic Tapes

Procedure for casting thin, multilayer ceramic membranes, commonly called tapes, involves centrifugal casting at accelerations of 1,800 to 2,000 times normal gravitational acceleration. Layers of tape cast one at a time on top of any previous layer or layers. Each layer cast from slurry of ground ceramic suspended in mixture of solvents, binders, and other components. Used in capacitors, fuel cells, and electrolytic separation of oxygen from air.

Collins, Earl R., Jr.↗

NASA NTRS1991

Fabrication Of Ceramic Mats

Process to make mats of fine zirconia filaments proposed. Ceramic mats formed by sintering mats of partially dried filaments extruded from slurry of ceramic powder, binder, and solvent. Mats of fine zirconia fibers easier to ball-mill than commercially available zirconia powder.

Collins, Earl R., Jr.↗

NASA NTRS1990

Precise Hinge Has Low Friction

Precise hinge rotates with minimal friction and without "slop". Axis of rotation at central axis of concentric, self-retaining assembly. Blades in same plane, and both edges of blades and apexes of grooves lie along same line, allowing free rotation without either binding or slop. Blades on rotor engage grooves on stator. Blades pivot about edges through arc defined by slotted openings in stator housing.

Collins, Earl R., Jr.↗

NASA NTRS1990

Implantable Electrode For Critical Locations

Implantable electrode holds itself in place until body tissue grows around it and retains it. Sheath covers electrode during implantation. Partially retracted after implantation and completely retracted after growth of tissue onto electrode. Intended to provide electrical stimuli to muscles having become inactive through accident or disease. Helps paraplegics and others to exercise voluntary control over arms and legs.

Collins, Earl R., Jr.↗

NASA NTRS1990

Computer access security code system

A security code system for controlling access to computer and computer-controlled entry situations comprises a plurality of subsets of alpha-numeric characters disposed in random order in matrices of at least two dimensions forming theoretical rectangles, cubes, etc., such that when access is desired, at least one pair of previously unused character subsets not found in the same row or column of the matrix is chosen at random and transmitted by the computer. The proper response to gain access is transmittal of subsets which complete the rectangle, and/or a parallelepiped whose opposite corners were defined by first groups of code. Once used, subsets are not used again to absolutely defeat unauthorized access by eavesdropping, and the like.

Collins, Earl R., Jr.↗

NASA NTRS1990

Stabilizing Wheels For Rover Vehicle

Proposed articulated, normally-four-wheeled vehicle holds extra pair of wheels in reserve. Deployed to lengthen wheelbase on slopes, thereby making vehicle more stable, and to aid vehicle in negotiating ledge or to right vehicle if turned upside down. Extra wheels are drive wheels mounted on arms so they pivot on axis of forward drive wheels. Both extra wheels and arms driven by chains, hydraulic motors, or electric motors. Concept promises to make remotely controlled vehicles more stable and maneuverable in such applications as firefighting, handling hazardous materials, and carrying out operations in dangerous locations.

Collins, Earl R., Jr.↗

NASA NTRS1990

Computer-Access-Code Matrices

Authorized users respond to changing challenges with changing passwords. Scheme for controlling access to computers defeats eavesdroppers and "hackers". Based on password system of challenge and password or sign, challenge, and countersign correlated with random alphanumeric codes in matrices of two or more dimensions. Codes stored on floppy disk or plug-in card and changed frequently. For even higher security, matrices of four or more dimensions used, just as cubes compounded into hypercubes in concurrent processing.

Collins, Earl R., Jr.↗

NASA NTRS1990

Robot Hand Would Adapt To Contours

Conceptual device uses hydraulic pressure to activate fingers. Projections on opposing fingers of proposed robot hand automatically conform to contours of object on contact. Pistons connected to common reservoir provide gentle, firm grip. Fingers communicate with each other via hydraulic pressure, without elaborate control system. Pistons move in and out, and tips slope to match contour of object. Their action tends to center object on finger. Hand used to grasp objects of various shapes and sizes. Conforming process passive; pressure of object on one or several pad elements forces other pad elements to touch it. Would not use elaborate mechanisms involving motors, cams, and cables.

Collins, Earl R., Jr.↗

NASA NTRS1990

Electrostatic Linear Actuator

Electrically charged helices attract or repel each other. Proposed electrostatic linear actuator made with intertwined dual helices, which holds charge-bearing surfaces. Dual-helix configuration provides relatively large unbroken facing charged surfaces (relatively large electrostatic force) within small volume. Inner helix slides axially in outer helix in response to voltages applied to conductors. Spiral form also makes components more rigid. Actuator conceived to have few moving parts and to be operable after long intervals of inactivity.

Collins, Earl R., Jr.↗

NASA NTRS1989

Mounts For Selective Rotation And Translation

Blade-in-groove bearings stacked to obtain necessary degrees of freedom. Mounting system allows panels to be tilted, rotated, and translated selectively. Developed for large solar reflectors or antennas composed of hexagonal panels about 6 ft. wide and 6 in. thick. With system, each panel tilted around two axes to focus antenna. At same time, each panel translates along these axes to accommodate thermal expansion and contraction without affecting focus.

Collins, Earl R., Jr.↗

NASA NTRS1989

Convergent strand array liquid pumping system

A surface-tension liquid pumping system is provided by one or more arrays of converging solid monofilament fibers or metal wires (strands) spaced apart at an input end to gather liquid, and gathered close together at the opposite end where menisci forms between wetted strands to force liquid in the direction of convergence of the strands. The liquid pumping system is independent of gravity. It is illustrated as being used in a heat pump having a heating box to vaporize the liquid and a condensing chamber. Condensed liquid is returned by the pumping system to the heating box where it is again vaporized. A vapor tube carries the vapor to the condensing chamber. In that way, a closed system pumps heat from the heating box to the evaporating chamber and from there radiated to the atmosphere.

Collins, Earl R., Jr.↗

NASA NTRS1989

Tamper-Resistant Secure Disposal Container

Closure device for secure waste containers prevents classified papers and other proprietary articles from being withdrawn when container turned on side. Has pendulum that swings comb into closed position when container turned on side. Suspended with axis of rotation perpendicular to axes of combs. Extends through D-shaped cam ring, attached to upper comb with standoff struts. When container tilted sideways, pendulum swings along arc side of D-shaped ring. Forces cam ring aside, moving upper comb toward closed position. If container tilted forward or backward, pendulum does not interfere with comb movement. Spring catches added to combs so if actuated and close container opening, they lock in place to prevent further tampering.

Collins, Earl R., Jr.↗

NASA NTRS1989

Convergent-Filament Nonmechanical Pump

Simple device induces small flow of liquid without help of moving parts, in presence or absence of gravity. Drops of liquid move on filaments from wide end of cone to narrow end. Gradually blend with drops on adjacent filaments to form large drops with menisci. Important use expected to be returning liquid condensate in heat pipes, and collection of samples from clouds or fog.

Collins, Earl R., Jr.↗

NASA NTRS1989

Energy efficient continuous flow ash lockhopper

The invention relates to an energy efficient continuous flow ash lockhopper, or other lockhopper for reactor product or byproduct. The invention includes an ash hopper at the outlet of a high temperature, high pressure reactor vessel containing heated high pressure gas, a fluidics control chamber having an input port connected to the ash hopper's output port and an output port connected to the input port of a pressure letdown means, and a control fluid supply for regulating the pressure in the control chamber to be equal to or greater than the internal gas pressure of the reactor vessel, whereby the reactor gas is contained while ash is permitted to continuously flow from the ash hopper's output port, impelled by gravity. The main novelty resides in the use of a control chamber to so control pressure under the lockhopper that gases will not exit from the reactor vessel, and to also regulate the ash flow rate. There is also novelty in the design of the ash lockhopper shown in two figures. The novelty there is the use of annular passages of progressively greater diameter, and rotating the center parts on a shaft, with the center part of each slightly offset from adjacent ones to better assure ash flow through the opening.

Collins, Earl R., Jr.↗

NASA NTRS1989

High density tape casting system

A system is provided for casting thin sheets (or tapes) of particles bound together, that are used for oxygen membranes and other applications, which enables the particles to be cast at a high packing density in a tape of uniform thickness. A slurry contains the particles, a binder, and a solvent, and is cast against the inside walls of a rotating chamber. Prior to spraying the slurry against the chamber walls, a solvent is applied to a container. The solvent evaporates to saturate the chamber with solvent vapor. Only then is the slurry cast. As a result, the slurry remains fluid long enough to spread evenly over the casting surface formed by the chamber, and for the slurry particles to become densely packed. Only then is the chamber vented to remove solvent, so the slurry can dry. The major novel feature is applying solvent vapor to a rotating chamber before casting slurry against the chamber walls.

Collins, Earl R., Jr.↗

NASA NTRS1989

Improved Flow-Controlling Vortex Generator

Symmetrical tangential streams control flow of radial primary streams. Vortex generator uses small secondary stream of fluid to control normally-larger primary stream. Improved version of vortex generator described in "Variable Control Port for Fluidic Control Device," (NPO-16603). Secondary, or control, flows entering tangentially through diametrically opposite ports set up swirling motion restraining primary flow. Pressure of secondary fluid in relation to primary fluid controlling factor. Like valve, vortex generator varies rate of flow of primary fluid from maximum value down to zero. When properly designed, requires low pressure differential between primary and secondary streams and expends relatively small amount of secondary fluid.

Collins, Earl R., Jr.↗

NASA NTRS1989

Energy-Efficient, Continuous-Flow Ash Lockhopper

Pressure balance in control gas prevents loss of reactor gas. Energy efficiency of continuous-flow ash lockhopper increased by preventing hot gases from flowing out of reactor vessel through ash-hopper outlet and carrying away heat energy. Stopping loss of reactor gases also important for reasons other than energy efficiency; desired reaction product toxic or contained to prevent pollution. In improved continuous-flow ash lockhopper, pressure-driven loss of hot gas from reactor vessel through ash-hopper outlet prevented by using control gas in fluidic flow-control device to equalize pressure in reactor vessel. Also enables reactor to attain highest possible product yield with continuous processing while permitting controllable, continuous flow of ash.

Collins, Earl R., Jr.↗