Jeffrey E. Mast
Automatic Position Calculating Imaging Radar with Low-Cost Synthetic Aperture Sensor for Imaging Layered Media
U.S. Patent 5,796,363
August 18, 1998
An imaging system for analyzing structures comprising a radar transmitter and receiver connected to a timing mechanism to allow a radar echo sample to be taken at a variety of delay times for each radar pulse transmission. The radar transmitter and receiver are coupled to a position-determining system that provides the x,y position on a surface for each group of samples measured for a volume from the surface. The radar transmitter and receiver are moved about the surface to collect groups of measurements from a variety of x,y positions. Return signal amplitudes represent the relative reflectivity of objects within the volume. The delay in receiving each signal echo represents the depth of the object in the volume and the propagation speeds of the intervening material layers. Successively deeper z planes are backward propagated from one layer to the next, with an adjustment for variations in the expected propagation velocities of the material layers that lie between adjacent z planes.

Fred Mitlitsky, Blake Myers, and Frank Magnotta
Lightweight Bladder Lined Pressure Vessels
U.S. Patent 5,798,156
August 25, 1998
A lightweight, low-permeability liner for graphite-epoxy-composite, compressed-gas storage vessels. The liner is composed of polymers that may or may not be coated with a thin layer of a low-permeability material-such as silver, gold, or aluminum-deposited on a thin polymeric layer or substrate formed into a closed bladder using torispherical or near torispherical end caps, with or without bosses therein, about which a shell made of a high strength-to-weight material, such as graphite-epoxy composite, is formed to withstand the storage pressure forces. The polymeric substrate may be laminated on one or both sides with additional layers of polymeric film. The liner may be formed to a desired configuration using a dissolvable mandrel or by inflation techniques. The liner can be used in most any type of gas storage system and is particularly applicable for hydrogen, gas mixtures, and oxygen used for vehicles, fuel cells, or regenerative fuel-cell applications.

Thomas E. McEwan and Gregory E. Dallum
Soliton Quenching NLTL Impulse Circuit with a Pulse Forming Network at the Output
U.S. Patent 5,804,921
September 8, 1998
An impulse-forming circuit that produces a clean impulse from a nonlinear transmission line compressed-step function without customary soliton ringing the circuit formed by means of a localized pulse-shaping and differentiating network, which shunts the nonlinear transmission line output to ground.

Thomas E. McEwan
Impulse Radar with Swept Range Gate
U.S. Patent 5,805,110
September 8, 1998
A radar range finder and hidden-object locator based on ultrawideband radar with a high-resolution swept-range gate. The device generates an equivalent time amplitude scan, with a typical range of 4 inches to 20 feet and an analog-range resolution on the order of 0.01 inch. A differential sampling receiver is employed to effectively eliminate ringing and other aberrations induced in the receiver by the proximity of the transmit antenna, so a background subtraction is not needed. Circuitry is thus simplified and performance improved. Several techniques are used to reduce clutter, and the antennas can be arranged in a parallel configuration or in a coplanar opposed configuration to significantly reduce main bang coupling.

John F. Cooper
Electro-osmotic Transport in Wet Processing of Textiles
U.S. Patent 5,810,996
September 22, 1998
Electro-osmotic (or electrokinetic) transport is used to efficiently force a solution (or water) through the interior of the fibers and yarns of textile materials for wet processing of textiles. The textile material is passed between electrodes that apply an electric field across the fabric. Used alone or in parallel with conventional hydraulic washing (forced convection), electro-osmotic transport greatly reduces the amount of water used in wet processing. The amount of water required to achieve a fixed level of rinsing of tint can be reduced, for example, from an industry benchmark of 20 pounds of water per pound of fabric to 1 to 5 pounds of water per pound of fabric.

Kar-Keung David Young
High Precision Redundant Robotic Manipulator
U.S. Patent 5,811,951
September 22, 1998
A high-precision, redundant robotic manipulator for overcoming contents imposed by obstacles or by a highly congested work space. One embodiment of the manipulator has four degrees of freedom and another embodiment has seven degrees of freedom. Each of these is configured with one selective compliant assembly robot arm (SCARA) to provide high stiffness in the vertical plane and a second SCARA to provide high stiffness in the horizontal plane. The seven-degrees-of-freedom embodiment also uses kinematic redundance to provide the capability of avoiding obstacles that lie between the base of the manipulator and the end effector (or link) of the manipulator. The additional three degrees of freedom are added at the wrist link of the manipulator to provide pitch, yaw, and roll. The seven-degrees-of-freedom embodiment uses one revolute joint per degree of freedom. For each of the revolute joints, a harmonic gear coupled to the electric motor is introduced, and together with properly designed based-servo-controllers, they provide an end point repeatability of less than 10 micrometers.


Laboratory Director Bruce Tarter was honored in November with the U.S. Navy League's Roosevelts Gold Medal Award for Science. In presenting the award, Victor Gainor, president of the League's New York Council, described Tarter's leadership as "challenging and inspirational" and added that the League is "proud to salute Dr. Tarter and the Livermore Lab for the important role they play in making our nation and the world a safer place to live."

Three Laboratory scientists have been elected Fellows of the American Physical Society. APS Fellowships recognize those who have made advances in knowledge through original research and have made significant and innovative contributions in the application of physics to science and technology.
Gail Glendinning was honored for "clear and illuminating experimental investigations for ablation-front Rayleigh-Taylor stability, laser imprinting, and nonlinear hydrodynamic instabilities relevant to inertial confinement fusion . . . , high-energy-density physics, and astrophysics."
Luiz Da Silva was chosen for his "pioneering use of X-ray lasers and laser generated shock waves to study high density plasmas." His work extended the study of high-density plasmas to conditions relevant to planetary science, astrophysics, and inertial confinement fusion.
Guy Dimonte was recognized for his "outstanding contributions to understanding turbulence and mixing in high-energy-density fluids by novel experimental techniques and facilities." He developed new target configurations for the Nova laser and a linear electric motor that can accelerate projectiles up to 1,000 g's to investigate fluid turbulence and mixing. His experimental results can be applied to study areas as diverse as volcanic islands, underground salt domes, astrophysics, and inertial confinement fusion.

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