Method and apparatus for gripping uniaxial fibrous composite materials

A strip specimen is cut from a unidirectional strong, brittle fiber composite material, and the surfaces of both ends of the specimen are grit blasted. The specimen is then placed between metal load transfer members having grit blasted surfaces. Sufficient compressive stress is applied to the load transfer members to prevent slippage during testing at both elevated temperatures and room temperatures. The need for adhesives, load pads, and other secondary composite processing is eliminated. This gripping system was successful in tensile testing, creep rupture testing, and fatigue testing uniaxial composite materials at 316 C

The GPRIME approach to finite element modeling

GPRIME, an interactive modeling system, runs on the CDC 6000 computers and the DEC VAX 11/780 minicomputer. This system includes three components: (1) GPRIME, a user friendly geometric language and a processor to translate that language into geometric entities, (2) GGEN, an interactive data generator for 2-D models; and (3) SOLIDGEN, a 3-D solid modeling program. Each component has a computer user interface of an extensive command set. All of these programs make use of a comprehensive B-spline mathematics subroutine library, which can be used for a wide variety of interpolation problems and other geometric calculations. Many other user aids, such as automatic saving of the geometric and finite element data bases and hidden line removal, are available. This interactive finite element modeling capability can produce a complete finite element model, producing an output file of grid and element data

Battery Cell Health Self-Test

This disclosure describes techniques for self-testing of battery health of electronic devices. Per techniques of this disclosure, a battery cell health state is determined by performing a self-test that emulates high power-draw and/or critical usage scenarios. The self-test is conducted at a likely inactive time for the device use based on user-permitted contextual factors. During the test, device charging is disabled so that the battery cell is isolated from its power source. The battery voltage is lowered to a predetermined voltage that is representative of a low state of charge by utilizing a power virus. Battery health parameters such as power consumption, state of charge, current being drawn from battery, battery voltage during the test, etc., are recorded. Based on the battery health parameters measured during the self-test, usage parameters are adjusted to mitigate brownout risk

Motion activated wireless reconnection

The time taken from the removal of a laptop or other device from a bag by a user to the establishment of connection to a wireless network can be significant, e.g., ten seconds or more. This disclosure describes techniques to reduce this delay to nearly zero. Per the techniques, upon detection of motion by on-board motion sensors of a device, the device wakes from a sleep state and automatically scans for and connects to a WiFi network

Determination of User Home Location for Emergency Services

This disclosure describes techniques to accurately determine a user’s home location for use in voice over WiFi (VoWiFi) emergency calls. Per techniques of this disclosure, with user permission, a user’s home location is determined on a user device based on location information and corresponding time signatures associated with the locations. Based on user location data, location clusters and sub-clusters are created. Based on the identified sub-clusters, a home cluster is identified and labeled as the user home location based on the location sub-cluster with time signatures representing the end of day and/or the location sub-cluster where the user has spent the longest stationary time. If the determined home location address is different from the current emergency address associated with the user, the user is prompted to update their emergency address to the newly determined home location address. The process is performed entirely on the user device

Cell Age Balancing For Wireless Earbuds

True wireless earbuds that include on-board batteries are popular. This disclosure describes techniques to balance cell aging of wireless earbuds and enable utilization of the full capacity of the battery cells of wireless earbuds. A fuel gauge value (available cell capacity) for each earbud is recorded. When the earbuds are charging, e.g., in a charging case, the fuel gauge value for each earbud is read. A cell age equalization mode is invoked if the difference between the available cell capacities meets a predetermined threshold. When the earbuds are placed in cell equalization mode, a code path may be configured to enable more frequent master-slave role switches between the earbuds, configure the earbud with the healthier cell automatically as the master earbud, and/or deactivate some compute functionality on the earbud with the weaker cell