Tech Briefs

Digitally Controlled, 12-V Precision Current Source for Extreme-Temperature Operation

NASA’s Jet Propulsion Laboratory, Pasadena, California Many control applications require precision, high-voltage-capable stimulus current drivers for sensor excitation. In particular, a requirement for a stimulus driver that can be primarily integrated into a motor feedback signal conditioning ASIC (application specific integrated circuit) for Martian environments is satisfied by this development.

Posted in: Electronics & Computers, Briefs

Read More >>

Scandate Cathode for High-Power, Long-Life Electric Space Propulsion

Applications include electron beam-stimulated lasers for high-power video projection systems and new-generation CT-scan x-ray imaging systems. John H. Glenn Research Center, Cleveland, Ohio Scandate cathodes are able to produce about 20 times the emission of conventional all-tungsten cathodes at the same temperature. Conversely, they operate at about 200 °C lower temperature for the same emission. Scandate cathodes have been studied since at least the 1960s. Between then and 2002, numerous approaches were investigated. All cathodes either did not work or degraded within a few thousand hours. The current nanoparticle approach appears to have overcome previous shortcomings.

Posted in: Electronics & Computers, Briefs

Read More >>

Hybrid Force/Stress Amplified Piezoelectric Energy Harvesting Transducer System

This design converts mechanical energy in the environment to electrical energy to power a device. Langley Research Center, Hampton, VA This innovation uses an active materials-based force-amplified mechanism and advanced piezoelectric materials for more efficient energy harvesting from mechanical shock and vibration. The harvested energy is stored in rechargeable batteries. The hybrid force/stress amplified transducer/actuator offers tens to hundreds of times higher electrical power output, up to ten times higher electromechanical energy conversion efficiency, and several orders of magnitude higher energy storage efficiency than conventional flex-tensional or multilayer stack transducers at the stress less than the fracture stress of the materials used in each element.

Posted in: Electronics & Computers, Briefs

Read More >>

Improved Battery Health Monitoring

Applications include electric vehicles, medical devices, robotics, power systems, and underwater unmanned vehicles. Neil A. Armstrong Flight Research Center, Edwards, California Battery health monitoring is an emerging technology field that seeks to predict the remaining useful life (RUL) of battery systems before they run out of charge. Such predictive measures require interpretation of large amounts of battery status data within a Bayesian prognostic framework.

Posted in: Electronics & Computers, Briefs

Read More >>

Space Modem GMSK Modulator

NASA’s Jet Propulsion Laboratory, Pasadena, California A high-rate GMSK (Gaussian Minimum Shift Keying) modulator was developed for space operation. Currently, multi-user modems are under development, and the GMSK modulator provides a way of packing more users within a space environment, especially for Mars exploration.

Posted in: Electronics & Computers, Briefs

Read More >>

Tailored 3D Fiber Architecture to Improve CVI Processing

Marshall Space Flight Center, Huntsville, Alabama An improvement has been made to the infiltration of 3D woven and 3D braided preforms that will lead to the manufacture of CMC (ceramic matrix composite) and C–C (carbon-carbon) composites based on 3D fiber architectures that have low residual porosity and smaller void sizes. Tailoring the fiber architectures by the use of several combinations of larger and smaller warp, fill, and z yarns formed pathways into the thickness of the fabrics to improve fluid flow through the preform during CVI (chemical vapor infiltration) processing.

Posted in: Manufacturing & Prototyping, Briefs

Read More >>

3D Microwave Print Head System for Melting Materials

This approach has applications in industry where solid materials need to be melted. NASA’s Jet Propulsion Laboratory, Pasadena, California There is a need to develop an efficient method for processing lunar regolith in support of future missions to colonize the Moon. A system for heating lunar regolith (“moon soil”) using microwaves for processing has been developed. It relies on an enhanced heating effect based on a large temperature gradient forming when a sample of lunar regolith under microwave radiation emits heat from its surface rapidly as the core is melting. Once the core melts, the sample absorbs microwave energy more readily. This molten lunar regolith would then exit the sample tube, and the lunar regolith could then be introduced into molds for forming a desired structure or building block.

Posted in: Manufacturing & Prototyping, Briefs

Read More >>