Electronics & Computers

Dynamic Response Determination of an Electronic Printed Circuit Board

Understanding the mechanical reliability of a PCB in an electronic system is an important part of assessing the reliability of the entire system. John Deere Electronic Solutions, Fargo, North Dakota; and John Deere India Pvt Ltd., Maharashtra, India Most of today’s automotive electronic systems are composed of two major mechanical elements: an equipment chassis or enclosure, and a printed circuit board (PCB) assembly. The PCB is composed of laminated copper and FR-4 glass epoxy. These systems often operate in severe vibration environments for extended periods without failing. The vibrations transmitted throughout the PCB induce strains in the connectors, components, and most importantly, the solder joints attaching the components to it.

Posted in: Electronics & Computers, Briefs

Read More >>

Wii Nunchuk Controller for ATHLETE Operations

NASA’s Jet Propulsion Laboratory, Pasadena, California The Arduino platform was used to develop an interface between two otherwise incompatible commercial devices in order to drive the ATHLETE (All-Terrain Hex-Limbed Extra-Terrestrial Explorer) rover over long distances. The Portable Operations Terminal consists of three distinct parts: a robot-mounted ruggedized laptop computer containing all of the “ground” support software needed to operate ATHLETE, a handheld computer capable of performing simple problem diagnosis and troubleshooting, and a handheld joystick based on the Wii Nunchuk used to drive ATHLETE with one hand. The physical modifications included an Arduino electronic prototyping board with custom firmware, and various support cables, lanyards, and enclosures to make the device survive the desert environment of the field test.

Posted in: Electronics & Computers, Briefs, TSP

Read More >>

CCSDS Telemetry Decoder VHDL Core

Costly ground support equipment can be eliminated. Goddard Space Flight Center, Greenbelt, Maryland A flexible Telemetry Decoder Core (TDC) has been designed to decode Consultative Committee for Space Data Systems (CCSDS) encoded telemetry data. The TDC can be used to eliminate costly ground support equipment by placing the telemetry decoding functions in an inexpensive, commercially available field programmable gate array (FPGA) integrated circuit instead of special-purpose printed circuit boards. The TDC can also be used in the design of telemetry systems by enabling end-toend simulation of these systems’ upfront simulation before any hardware is built. The TDC was developed for the Global Precipitation Measurement (GPM) project and because of its success on that project, it will be used to verify telemetry on the Magnetospheric Multiscale (MMS) project.

Posted in: Electronics & Computers, Briefs, TSP

Read More >>

Thermal Response of a High-Power Switch to Short Pulses

Simulations are used to calculate temperature changes that occur inside semiconductor switch modules, where measurement is not possible. Army Research Laboratory, Aberdeen Proving Ground, Maryland Semiconductor switch modules composed of Super Gate Turn-Off Thyristors (SGTOs) have been evaluated. The switches are intended to handle kiloamplevel currents and may dissipate peak powers measured in megawatts. Recent experiments measured the response of a switch module composed of eight SGTOs to single-short, high-current pulses. Simulations of those experiments were performed to calculate the temperature changes that occur inside the devices, where measurement is not possible. Worst-case operating conditions in which the switches handle several pulses within the space of 4 or 5 seconds (s) also were simulated. Modeling and simulation were performed with SolidWorks 3D modeling software and SolidWorks Simulation computational fluid dynamics software from Dassault Systèmes.

Posted in: Electronics & Computers, Briefs, TSP

Read More >>

Battery Fault Detection with Saturating Transformers

This monitoring system for high-power battery health could be useful for electric cars and the aerospace industry. Lyndon B. Johnson Space Center, Houston, Texas A monitoring network has been created that can be added to a battery consisting of many parallel cells. This network allows the health of individual cells, as measured by the current that they produce under load, to be monitored. If one or more cells are producing less current than the others, the network allows the discrepant cell(s) to be sensed and located.

Posted in: Electronics & Computers, Briefs, TSP

Read More >>

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, TSP

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, TSP

Read More >>

White Papers

Oscilloscope Fundamentals
Sponsored by Rohde and Schwarz A and D
How to Choose the Right Sensor for Your Measurement System
Sponsored by National Instruments
White Papers: Using FPGAs to Improve Embedded Designs
Sponsored by Sealevel
Specialized Adhesives Withstand Thermal Cycling
Sponsored by Master Bond
Selection of Materials for Medical Applications
Sponsored by RTP
3D Printing in Space: The Next Frontier
Sponsored by Stratasys

White Papers Sponsored By: