Special Coverage

Clamshell Sampler
Shape Memory Alloy Rock Splitter
Deployable Extra-Vehicular Activity Platform (DEVAP) for Planetary Surfaces
2016 Create The Future Design Contest Open For Entries
The Future of Exploration Starts With 3D Printing

Advances in Measurement of Skin Friction in Airflow

This system implements a combination of established experimental techniques and advanced image processing. The surface interferometric skin-friction (SISF) measurement system is an instrument for determining the distribution of surface shear stress (skin friction) on a wind-tunnel model. The SISF system utilizes the established oil-film interference method, along with advanced image-data-processing techniques and mathematical models that express the relationship between interferograms and skin friction, to determine the distribution of skin friction over an observed region of the surface of a model during a single wind-tunnel test.

Posted in: Briefs


Ginger N. Flores, LOCAD Project Manager, NASA Marshall Space Flight Center, Huntsville, AL

Diagnosis on Earth is a fairly simple procedure, done at any hospital or medical center. In space flight, however, where doctors and even basic medical equipment may be lacking, falling ill is a serious matter for both astronaut and ground control. Using horseshoe crab blood as a reactive agent, the Lab-On-a-Chip Application Development-Portable Test System (LOCAD-PTS) is a handheld device developed by NASA researchers to help identify microorganisms. Ginger N. Flores is the LOCAD project manager.

Posted in: Who's Who



United Electronics Industries, Canton, MA, has introduced the UEILogger series of data loggers and recorders. The logger "Cube" contains the logger engine and either three or six I/O slots. The logger is matched to the user's application by installing the appropriate I/O boards from more than 20 different available boards. A single 4 x 4.1 x 5.8" logger cube can provide up to 150 A/D channels or 288 digital I/O. The logger requires no programming, and the logging application is configured using a Windows-based application that sets up the logger and extracts data from the logger's memory. The software allows users to set input and output ranges, sample/update rates, and signal conditioning from pull-down menus. The program may be downloaded via the unit's standard Ethernet port or stored on the SD card. The logger supports sample rates up to 100 samples per second on each I/O channel or port. Data is logged onto standard SD cards; a 2-Gig SD card is included that holds more than 500 million 16-bit A/D readings.

Posted in: Products


Spiral Orbit Tribometer

Friction and lubricant degradation rate can be quantified rapidly. The spiral orbit tribometer (SOT) bridges the gap between full-scale life testing and typically unrealistic accelerated life testing of ball-bearing lubricants in conjunction with bearing ball and race materials. The SOT operates under realistic conditions and quickly produces results, thereby providing information that can guide the selection of lubricant, ball, and race materials early in a design process.

Posted in: Machinery & Automation, Mechanics, Briefs, TSP


Predicting Rocket or Jet Noise in Real Time

Measurement data can be analyzed in real time. A semi-empirical theoretical model and a C++ computer program that implements the model have been developed for use in predicting the noise generated by a rocket or jet engine. The computer program, entitled the Realtime Rocket and Jet Engine Noise Analysis and Prediction Software, is one of two main subsystems of the Acoustic Prediction/Measurement Tool, which comprises software, acoustic instrumentation, and electronic hardware combined to afford integrated capabilities for real-time prediction and measurement of noise emitted by rocket and jet engines. [The other main subsystem, consisting largely of acoustic instrumentation and electronic hardware, is described in “Wireless Acoustic Measurement System,” which appears elsewhere in this section.

Posted in: Briefs


Computational Workbench for Multibody Dynamics

PyCraft is a computer program that provides an interactive, workbench-like computing environment for developing and testing algorithms for multibody dynamics. Examples of multibody dynamic systems amenable to analysis with the help of PyCraft include land vehicles, spacecraft, robots, and molecular models. PyCraft is based on the Spatial-Operator-Algebra (SOA) formulation for multibody dynamics. The SOA operators enable construction of simple and compact representations of complex multibody dynamical equations. Within the PyCraft computational workbench, users can, essentially, use the high-level SOA operator notation to represent the variety of dynamical quantities and algorithms and to perform computations interactively. PyCraft provides a Python-language interface to underlying C++ code. Working with SOA concepts, a user can create and manipulate Python-level operator classes in order to implement and evaluate new dynamical quantities and algorithms. During use of PyCraft, virtually all SOA-based algorithms are available for computational experiments.

Posted in: Briefs, TSP


SiC Multi-Chip Power Modules as Power-System Building Blocks

Fault-tolerant power-supply systems could be constructed and expanded relatively inexpensively. The term “SiC MCPMs” (wherein “MCPM” signifies “multi-chip power module”) denotes electronic power-supply modules containing multiple silicon carbide power devices and silicon-on-insulator (SOI) control integrated-circuit chips. SiC MCPMs are being developed as building blocks of advanced expandable, reconfigurable, fault-tolerant power-supply systems. Exploiting the ability of SiC semiconductor devices to operate at temperatures, breakdown voltages, and current densities significantly greater than those of conventional Si devices, the designs of SiC MCPMs and of systems comprising multiple SiC MCPMs are expected to afford a greater degree of miniaturization through stacking of modules with reduced requirements for heat sinking. Moreover, the higher-temperature capabilities of SiC MCPMs could enable operation in environments hotter than Si-based power systems can withstand.

Posted in: Briefs


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