Virginia Tech Intellectual Properties Inc

University of Houston System

Jang-Horng Yu

Wei-Kan Chu

Didier Lefebvre

Quark Yung-Sung Chen

Eujeong Lee

Ki Bui Ma

David A Dillard

Yevgeniy Postrekhin

A method and apparatus for determining bulk material constants such as Poisson's ratio and the ratio of shear modulus to bulk modulus for elastomeric materials, including, but not limited to elastomers, rubbers, gels and sealants is disclosed. The bulk material properties are determined by measuring the pressure change of the elastomeric material when the elastomeric material is subjected to an applied pressure. The changes in the bulk material property due to temperature or a the addition of a diluent may also be determined. The apparatus includes a container that holds the elastomeric material. A pressure sensor is located in the container and is positioned to measure the pressure of the elastomeric material. The signal from the pressure sensor along with the applied pressure is used to determine a bulk material property such as Poisson's ratio or the ratio of shear modulus to bulk modulus for the elastomeric material.

Method and apparatus for determining bulk material properties of elastomeric materials

A torque/reactive momentum wheel control system for use in satellites for dynamic attitude maintenance and alteration where the flywheel of each momentum wheel is levitated by a high-temperature superconducting element repulsively interacting with permanent magnets in the flywheel. The spin rate (rpm) of the flywheel being controlled by either an active magneto or electromagneto drive system. Each momentum wheel is cooled by a cryo-cooler and can have a total weight of about 10 Kg to a fraction of 1 Kg and delivering 3.5 Js with less than 1 W loss.

Satellite angular momentum control system using magnet-superconductor flywheels

Growing community of inventors

Blacksburg, VA, United States of America

Jang-Horng Yu