Monolithic Power Integrated Circuits for Merging Power Electronics, Management, and Distribution, Phase Idata.nasa.gov | Last Updated 2018-07-19T08:23:32.000Z
APIQ Semiconductor proposes development of a scalable, wide bandgap (WBG) monolithic power integrated circuit (MPIC) technology for power electronic conversion, management, and distribution. The proposed WBG microelectronics are to be based upon low defect, homogeneous gallium nitride (GaN) based materials using native GaN substrates. The technology to be developed will replace silicon power switches and drivers in power electronics systems to yield high efficiency, high density, reliable module based systems. Inclusive in the proposal are devices for 1200 V or more power switching and digital integration. Devices will be evaluated for high temperature and heavy ion radiation hardness, with performance improvements over competing technologies expected from low materials defects and carefully managed electric field profiles.
- API data.nasa.gov | Last Updated 2018-07-20T07:17:16.000Z
The investigation of the coating friction as a function of time is important to monitor the ball bearing heath. Despite the importance of the subject mater, there is a crucial lack of information in the literature about coating life and friction force in ball bearings as coating wear of progressively increases. Here we propose to develop a strategic space vehicle health monitoring system that will identify potential and/or imminent lubrication problems, analyze these parameters in real time, and provide direct input so that these problems are mitigated prior to failure. We will set up a lab experiment environment with a universal microtribometer and acoustic emission sensors measuring the signals associated with wear and the changes that tend to occur as a function of time. Friction force and acoustic signal will be measured with respect to the bearing condition. To capture the dynamic nature of friction evolution, we propose to extract the temporal transient features from the sensing data and develop Hidden Markov Models with four distinct states associated with four operation conditions of the ball bearing. Our system uniquely combine both physics-based and stochastic models for the online diagnosis.
- API data.nasa.gov | Last Updated 2018-07-19T07:32:14.000Z
A trajectory design tool is sought to leverage chaos and nonlinear dynamics present in multi-body gravitational fields to design ultra-low energy transfer trajectories, with applications to continuously thrusting spacecraft. Specifically invariant manifolds associated with liberation points will be leveraged in an algorithm to generate initial solutions which will be fed into higher fidelity optimization tools. The tool will be used in a case study to design an interplanetary transfer trajectory for a CubeSat using solar electric propulsion. By combining the inherent efficiency of solar electric propulsion, with the fuel savings available through invariant manifold trajectory design, it is expected the required fuel will be cut significantly, as compared to spacecraft using chemical rockets and Hohmann transfers. The research will contribute to the proliferation of new in-space propulsion systems by providing a simulation-based design tool specifically targeted at such systems. Thus the research answers the call of TABS sections 2.4, In-Space Propulsion Supporting Technology, and 11.18 Simulation Based Systems Engineering. Furthermore, as the algorithm is computationally improved, the trajectory software may be implemented onboard spacecraft, enabling online trajectory design and optimization. Therefore the research meets the call of TABS section 4.5, Autonomy. Finally, ultra-low energy trajectories can be used to cheaply send scouting spacecraft for precursor missions. CubeSat missions, enabled by the proposed research, could serve to study and map human exploration destinations prior to human arrival. Thus the proposed research meets the calls for Destination, Reconnaissance and Mapping, as in section 7.1.1, as well as Modeling, Simulations and Destination Characterization, as in section 7.6.1.
- API data.nasa.gov | Last Updated 2018-08-02T15:26:18.000Z
<p>The primary objective of this activity is to develop, design, and test (DD&T) the QUAD-core siTARA (QUATARA) computer to distribute computationally intensive processes such as: communication, sensors, attitude determination, attitude control, cameras, robotic manipulators, and science payloads. An example of the current state-of-the art for a COTS CubeSat flight computer is, a 16 bit 80 MHz Microchip dsPIC33 microcontroller capable of managing the satellite attitude determination, control system, communication system, power, and science payloads. Adding more capability to these COTS flight computers required the development, under a previous CIF proposal, of the Modular Attitude Determination System (MADS) board. MADS lessened the I/O load from the flight computer so it could focus on higher priority tasks such as managing a Real-Time Operating System (RTOS) or carrying out an attitude control algorithm. The MADS board utilized a 16 bit 80 MHz Texas Instruments ARM Cortex-M4 Stellaris microcontroller to execute the attitude determination algorithm independently of the dsPIC33 flight computer. Once the MADS board processes the data, the dsPIC33 receives the estimated states and determines the desired attitude control.</p><p>The addition of cameras, proximity sensors, robotic manipulators, thruster systems, complex science payloads and video guidance systems, would cause current CubeSat flight computers to be overwhelmed. Because of the desire to expand the capabilities of CubeSats, the innovation of the QUATARA architecture enhances the capabilities of data handling and computer processing by replacing the 16 bit 80 MHz microcontrollers with four 64 bit 1 GHz microprocessors. The QUATARA allows for tasks to be processed at a faster rate not only because of the difference in clock speed between the platforms but also because of the fact that there are four individual microprocessors which can run these tasks independently without the need to serialize the execution of the code like in a single microcontroller.</p><p>The QUATARA computer aims to be fault-tolerant by means of a software voting scheme to guard against the effects of Single Event Effects (SEE) such as Single Event Upsets (SEU). Each ‘node’ (Gumstix Computer-On-Modules (COM)) of the QUATARA computer will be connected to its own set of sensors and actuators. These individual nodes will collect their respective data and share it between themselves over a data bus (such as RS-485). Once each node has all the data from all of the other nodes it will process it and come up with a result. This result can then be used to determine if a node is considered as ‘failed’ and that node then needs to be disabled, (this can be done by ignoring future data received from that node or by completely shutting it off). In the case a node is lost a support node is available to be switched in for the failed node. This support node will focus on low priority tasks, (such as housekeeping), if it is not required as a voting node. Synchronization between the nodes can be maintained by having a precise timing source on each of the processors, (such as a ticking timer interrupt routine), that ticks at a set time interval. This timing information will be passed between the nodes and the tick rate of the interrupt routine will be modified as required to ensure that all of the nodes data remains in sync.</p>
- API data.nasa.gov | Last Updated 2018-07-19T09:03:03.000Z
This proposal addresses the need for miniature, narrow-linewidth, deep UV optical sources that operate at very low ambient temperatures for use in advanced in situ planetary science instruments for non-contact detection and classification of trace amounts of organic, inorganic, and biogenic materials using Raman and native fluorescence spectroscopic methods. The sources include aluminum gallium nitride semiconductor lasers and ultra-narrow-linewidth transverse excited hollow cathode lasers emitting between 210 nm to 250 nm, a spectral range with demonstrated higher detection sensitivity and specificity than sources emitting at longer wavelengths. Applications include non-contact robot-arm or body mounted chemical imaging instruments and detectors for direct analysis of trace levels of chemical species containing C, N, H, O, S, Cl, on surfaces or as extractions from soil, rock, or ice. We have achieved the highest recorded deep UV semiconductor internal quantum efficiencies at wavelengths below 250 nm. But continuing difficulties of attaining laser emission and prospects for narrow line-width compatible with Raman applications has caused us to redirect a significant portion of the Phase II effort to another class of deep UV laser with a more proven UV Raman track record and the potential for miniaturization for robot-arm-mounted applications.
- API data.nasa.gov | Last Updated 2018-07-19T08:53:08.000Z
We proposed to design, build and test a high temperature Pneumatic Drill and Trencher system for Venus subsurface exploration. The Venus Drill and Trencher will be hybrid systems capable of acquiring surface and subsurface regolith as well as pulverized rocks (i.e. cuttings) from depth (the exact depth will be driven by the science requirement). The drill and the trencher unique sample delivery system will be able to transfer samples as they are being acquired, directly into the science instruments. Hence, these systems could be a single deployment system – it will have to drill/cut down once to deliver samples, and never retract. If the Venus Drill and/or Trencher will be deployed from a robotic arm, the system could be used multiple times. If the Venus Drill or the Trencher will be body mounted or mounted to a single degree of freedom system (spring deployable single action arm), it would be deployed once. Depending on the deployment requirements, the Drill and the Trencher could require just one actuator, while the remaining degrees of freedom (lowering the system to the ground and/or deploying the system some distance from the lander) could be achieved by a set of springs and hinges.
- API data.nasa.gov | Last Updated 2018-07-19T07:26:31.000Z
<p>The Planetary Instrument Definition and Development Program (PIDDP) supports the advancement of spacecraft-based instrument technology that shows promise for use in scientific investigations on future planetary missions. The goal is to define and develop scientific instruments or components of such instruments to the point where the instruments may be proposed in response to future announcements of flight opportunity without additional extensive technology development.<p/><p>Results of PIDDP have contributed to the development of flight hardware flown on, or selected for, many of NASA's planetary missions. The instrument technology selected through PIDDP addresses specific scientific objectives of likely future science missions. Instrument definition and development studies take place at several stages, including feasibility studies, conceptual design, laboratory breadboarding, brassboarding, and testing of critical components and complete instruments. The technology readiness level (TRL) that PIDDP supports is TRL 1-6. For immature or particularly complex new instruments, proposers initially may choose to only define or develop the most risky components. When the proposed effort is for a component only, the proposed effort describes one or more likely scenarios for possible follow-on instrument development. Scientific objectives of the instruments, proposed follow-on instruments, and future candidate missions are discussed in the proposal for each selected activity. It is the responsibility of the proposer to demonstrate how their proposed instruments address significant scientific questions relevant to stated NASA goals and not for NASA to attempt to infer this.</p>
- API data.nasa.gov | Last Updated 2018-07-19T02:46:54.000Z
Galileo Orbiter Magnetometer (MAG) calibrated high-resolution data from the Earth-2 flyby in spacecraft, GSE, and GSM coordinates. These data cover the interval 1992-11-03 to 1992-12-19.
- API data.nasa.gov | Last Updated 2018-07-19T16:16:35.000Z
The objective of this project is to demonstrate intelligent health and maintenance status determination and predictive fault diagnosis techniques for NASA rocket engines under online and offline conditions from either on-board or maintenance, test and analytic data. AGNC proposes a Health and Maintenance Status Determination and Predictive Fault Diagnosis System (HMSD/PFDS). The fuzzy qualitative model for model-based residual generation and the rule-based evaluation of residuals using neural-fuzzy combination are defined. Intelligent data fusion strategies for health and maintenance determination and predictive fault diagnosis are developed for rocket engine systems/subsystems. The goal is to ensure safety, cost reduction, graceful degradation and re-optimization in the case of failures, malfunctions and damages. Kalman filter based and rule based evaluation of residuals using neural-fuzzy combination are developed. The use of fuzzy qualitative models takes into account the uncertainties associated with behavior descriptions and incorporates available expert failure symptom knowledge to recognize the particular failure features. Actual or simulated rocket engine sensed or derived data are utilized to evaluate the effectiveness of the health and maintenance determination and fault prognosis approaches for NASA platforms. Phase I is devoted to the HMSD/PFDS design and simulation. Phase II will result in development of a functional prototype.
- API data.nasa.gov | Last Updated 2018-07-19T09:16:33.000Z
Munro offer an innovatiive, intelligent, fully integrated hardware and software cockpit system solution for handling many General Aviation (GA) and UAV emergencies so as to minimize NextGen ATM disruption while saving lives. This ADS-B-ER system will provide GA airplanes and UAVs automated -ER trajectories to the nearest suitable airport avoiding terrain/obstacles, hazardous weather and restricted airspace.