- API data.nasa.gov | Last Updated 2018-07-19T07:37:24.000Z
One of the biggest problems facing spaceflight today is the accumulation of orbital debris because it threatens the successful operation and lifespan of existing satellites. The predominant cause of orbital debris is the jettisoning of launch vehicle upper stages after their usefulness is over once a rocket reaches orbit altitude. While their orbit slowly decays, these obsolete upper stages then share an orbit with valuable satellites presenting a danger to those satellites by either hitting them or hitting other rocket bodies and breaking into smaller pieces which can be just as dangerous but become much harder to track. These collisions potentially add an exponentially growing number of debris in orbit. One way to reduce the number of rocket bodies in orbit is to have a drag device connected to the upper stage of the launch vehicle that deploys once it is jettisoned from the payload. The intent of this device is to increase atmospheric drag and thus accelerate deorbit. By reducing the time debris is in orbit we will reduce the amount of debris thereby reducing the threat to satellites. When designing this device, it is important to minimize the packaged mass and volume of the final design to minimize the impact on the launch vehicle payload capacity. This project requires background research to accumulate data on upper stage sizes and masses, final orbits, and the current time it takes them to deorbit. An orbital mechanics review would be required to determine the effectiveness of the drag device compared to size. This research will help to develop initial requirements to start the design phase of the device. The design depends greatly on the materials and the dynamics of the device. It requires a flexible membrane to allow packaging, and foldable booms to stiffen the membrane once it is deployed. These will most likely be made from composite materials. The dynamics will be determined through computer models and simulations, followed by the building of various prototypes to test the deployment and folding configurations. Testing the deployment will occur in three phases. The first is by offloading the gravity within the lab to facilitate quick design iterations based on test results. The second is testing the deployment in a reduced gravity aircraft for higher fidelity testing. Finally, it will be tested in space on either a cubesat or launch vehicle upper stage. The results of each round of testing will allow the design and models to be improved. The research required for this device applies to the technology area 12.3 Mechanical Systems because of the subsection 12.3.1 Deployables, Docking and Interfaces. This lower level element emphasizes the importance of being able to overcome the constraints of launch vehicle fairing size. The area of deployable space structures is still a fairly new research topic with a lot of room for development and study. This project will definitely help to increase the body of knowledge on the dynamics, design techniques, and testing techniques. The necessity for a reliable restraint/release mechanism will benefit development research, as well, as this is a very important aspect of any deployment system. The flexible sail material will require development and research into how flexible membranes stow and respond to the environment of space. Finally, it is possible that the goal of this project will necessitate a fairly large deployable, which would increase research data for large lightweight stiff deployables.
- API data.nasa.gov | Last Updated 2018-07-19T07:45:37.000Z
Physical Sciences Inc. (PSI) proposes to develop new solar cells based on a ferroelectric semiconductor absorber material that can yield a 30% increase in efficiency and a 20% increase in specific power compared with current triple-junction III-V cells. These gains will be realized by exploiting a unique charge separation mechanism in ferroelectrics that enables open-circuit voltages many times the band gap, leading to maximum power conversion efficiencies exceeding the conventional Shockley-Queisser limit (33%). PSI and team members will create photovoltaic cells based on Earth-abundant SnS stabilized in a ferroelectric state by epitaxial strain engineering. By combining above-gap cell voltages with the high absorption coefficient (<1 x 105 cm-1 at 500 nm), low density (5.22 g/cm3), and ideal band gap (1.1 eV) of SnS, a mass-specific power density of 120 kW/kg (mass of absorber material, 1 um absorber thickness) is projected. In addition, a maximum cell efficiency of >45% is anticipated to be achievable. Importantly, these cells will also offer improved radiation resistance due to the reduced carrier diffusion lengths required by the unique ferroelectric charge separation mechanism. During Phase I, PSI, guided by first-principles calculations conducted by the PARADIM Center at Cornell University, will demonstrate room-temperature ferroelectric ordering in SnS through epitaxial strain engineering. During Phase II, PSI and Lawrence Berkeley National Laboratory will demonstrate the potential of the proposed absorber by achieving above-band gap open-circuit voltages in prototype cells. During a Phase III effort, the efficiency of these cells will be increased to a target value of 45% through reduction of intrinsic defects, leading to substantial improvements in cell size, weight, and power output.
- API data.nasa.gov | Last Updated 2018-09-07T17:46:54.000Z
Scientific/Technical/Management Science Goals and Objectives: A major goal of the NASA planetary space program has been the search for life in our solar system. On Mars, this effort has been focused on the successful search for water and habitability. The next step will be searching specific locations for signs of past life. One of the most promising places are the hydrothermal sinter deposits in the Nili Patera caldera of the Syrtis Major volcano. These deposits would have been long-lived, with the suitable environmental conditions and provide a well-mapped feature for a targeted mission. To prepare for this type of mission, we propose a series of experiments and field operations to develop the required methodologies. Operating at an extinct hot spring deposit in a Martian analog and extreme life environment in Iceland, we will collect samples and in-situ measurements to determine the resolutions and data sets required to answer the key mission objectives. We will also test trafficability to determine the spacecraft capabilities required for mission success. The proposed advancements break down into the categories of Science, Science Operations and Technology. Science objectives will focus building on the extensive set of terrestrial literature to answer questions specific to this mission. For example, how do we identify all potential signs of life preserved in the sinters and how to sinters record signs of environmental and volcanic properties. Specific to this proposal will be to understand what spacecraft instruments will be required to answer these questions. Science Operations will focus on the suite of instruments needed to operate together to answer the mission goals and what type of samples and mobility will be required for success. The Technology section will be to develop the methods to meet the requirements determined by the science effort. This includes sample collection and handling methodology and determining a plan to develop currently available field instruments into planetary capable versions. Methodology: Dr. Skok will lead a diverse team of hydrothermal, biological and instrumental experts to study a comparable hot spring deposit in Iceland to examine all the potential mission issues and scenarios, along with sample requirements. A combination of lab analysis of collected samples and in-situ deployment of field instruments will be used to prepare for this future mission. Relevance to Planetary Science and Technology Through Analog Research: This proposal meets the stated PSTAR goal of funding projects to planetary analog sites to develop the technologies and methodologies required for future missions, especially to extreme environments. Hot spring environments are key habitats on Earth and provide a planetary independent energy source and habitable zone.
- API data.nasa.gov | Last Updated 2018-07-19T08:28:13.000Z
Managing teams of unmanned vehicles is currently time-consuming and labor intensive. There needs to be a way to control multiple UAV teams with minimal human oversight. The proposed innovation builds on and combines several technologies we have developed to create an architecture and set of software methods that will achieve this goal, significantly advancing the state of the art. The proposed innovations are based on our NASA-funded Aurora planning, resource allocation, and scheduling framework, which has proved optimal in many, many diverse domains, including UAV scheduling; a Probabilistic RoadMap Planner (PRMP) to plan detailed real-time UAV routes to rapidly satisfy and optimize a large number of simultaneous constraints and objectives; the asynchronous consensus-based bundle algorithm (ACBBA) for UAV-to-UAV task negotiation; and the concept of a play (from sports) represented using behavior transition networks (BTNs). The ultimate goal of this proposed effort is to allow intelligent UAV team coordination and control in an intelligent, predictable, and robust way, with little cognitive load on the human users. This will require intelligent real-time planning, role allocation, negotiation, and detailed path planning and, when communication is not possible, autonomous, intelligent, adaptive behavior by the UAVs. In Phase I, we will develop the required AI techniques to automate all aspects of intelligently executing, recommending, and/or automatically selecting appropriate plays, robustly assigning roles and planning routes, and adaptively executing each role, robustly and predictably in environments with varying levels of uncertainty. We will design the ultimate system and, to absolutely prove its feasibility, prototype all aspects of it in Phase I on *actual, physical UAVs*.
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 2018-07-19T08:31:35.000Z
<p>WRANGLER will accomplish these functions by combining two innovative technologies that have been developed by TUI: the GRASP deployable net capture device, and the SpinCASTER tether deployer/winch mechanism. Successful testing of both technologies in a microgravity environment has established these technology components at mid-TRL maturity. The leverage offered by using a tether to extract angular momentum from a rotating space object enables a very small nanosatellite system to de-spin a very massive asteroid or large spacecraft. The WRANGLER system is suitable for an incremental development program that will validate the technology through an affordable test flight in which a nanosatellite launched on a rideshare opportunity would capture and de-spin the upper state used to launch it.</p>
- API data.nasa.gov | Last Updated 2018-07-19T09:35:53.000Z
The proposed innovation is an automated UAS mission planning system that will rapidly identify emergency (contingency) landing sites, manage contingency routing, and dynamically evaluate route changes for viability and safe operations in the NAS. Specifically, RAMPS will feature a pre-flight contingency planning capability that rapidly determines viable alternate/emergency landing sites based on a UAS's contingency ability and safe routing restrictions. RAMPS will include an in-flight dynamic contingency management capability that assesses ATC-requested re-routing and threats posed by weather to determine feasibility of modifications to the UAS flight trajectory. RAMPS can operate as a recommender system, providing operators with a narrow list of best options to help facilitate timely decision-making. RAMPS capabilities will provide UAS Operators with valuable time saving examination of a proposed route and possible contingency operations along that route – automating what has been an exceptionally tedious and lengthy manual process during mission planning. The in-flight component of RAMPS will provide the UAS operator with a dynamic mission evaluation tool – exceptionally important when a reconnaissance and surveillance mission is introduced into the routing planning process.
- API data.nasa.gov | Last Updated 2018-07-19T07:36:44.000Z
In NASA's 2014 Strategic Plan, Objective 1 specified the necessity to "expand human presence into the solar system and to the surface of mars to advance exploration, science, innovation, benefits to humanity, and international collaboration". As a part of fulfilling this objective, the strategic plan aims to send a human mission to mars in the 2030s. The advancement of in-space propulsion technologies is essential in order to fulfill this objective. NASA's most recent In-Space Propulsion Systems Road Map (TABS 02) cites the need to develop technologies which "enable much more effective exploration of our Solar System". More effective in-space propulsion systems must be mission enabling as well as reduce transit times, increase payload mass, and decrease costs. For a human mars mission, the in-space propulsion of choice should be capable of high thrust levels and high specific impulse to reduce transit time. A non-chemical propulsion technology, nuclear thermal propulsion (NTP), has been extensively tested in the United States and former Soviet Union. A NTP engine has the potential for twice the specific impulse of the best chemical engines (880 - 900 s) and 25 - 500 klbf thrust (100 - 2,200 kN). Thus, this technology is expected to reduce transit time and launch mass, therefore reducing mission costs. These attributes allow increased mission flexibility by increasing available payload mass and enabling longer stays on mars. Because of the unique advantages nuclear thermal propulsion can offer, in the National Resource Council's review of NASA's InSpace Propulsion Systems Roadmap, nuclear thermal propulsion was ranked as a high priority for in-space propulsion development. Under NSTRF15, the goal of this project is to aid the development of nuclear fuel forms for use in a nuclear thermal rocket (NTR). This will be completed through the identification and qualification of nuclear fuel form property data using non-nuclear testing. This data is essential in order to model fuel behavior and predict fuel performance as well as prepare nuclear fuel forms for eventual irradiation testing. Previous NTP programs (such as the NERVA/Rover program) took the approach of testing nuclear fuels through nuclear operation of a full scale reactor core. However, this methodology is costly and subject to stringent safety requirements. Recent research developments have shown that NTP fuel forms cannot be identically "re-captured" from past NTP programs because of the loss of manufacturing capabilities. Therefore, new manufacturing processes must be developed to mature fuel forms to be able to operate under the desired conditions for the NTR core and new property data must be obtained. Lessons learned from past NTP programs have shown that certain thermal and material properties of past NTP fuel forms directly correlate to the potential for successful NTR operation and high temperature performance. Since new manufacturing methods are needed for the development of NTP fuel forms, the thermal and material properties data archived from previous programs is not directly applicable for fuel performance simulations and the ultimate fuel selection process. The primary research objective of this project is to characterize a NTP fuel form which can withstand operating conditions of over 2800 K in a hot hydrogen environment. Secondary objectives will evaluate fuel performance at expected in-core vibration, pressure, and temperature gradients associated with operation. In order to meet project objectives, the methods of this project will consist of: 1) selection of fuel form chemistry and manufacturing processes, 2) Non-nuclear fuel testing and characterization of fuel material and thermal properties, and 3) Computational fuel modeling for expected operating conditions. NASA Marshall Spaceflight Center and affiliated research centers will provide the unique research facilities to ensure this project's success.
- API data.nasa.gov | Last Updated 2018-07-19T08:26:53.000Z
<p>The goal of this project is to develop a specialized GPS sensor prototype to enable high-performance GPS navigation for future cis-lunar and lunar missions. This sensor will be based on the NavCube, the next-generation version of the record-setting high-altitude MMS-Navigator GPS receiver. The proposed GPS sensor will target future lunar missions including robotic and human spaceflight applications. The proposed lunar GPS sensor will combine enhanced GPS signal processing and use the Goddard Enhanced Onboard Navigation System (GEONS) flight software to provide position and timing information for future lunar missions and cis-lunar missions, and will benefit crewed and un-crewed science and exploration missions.</p>
- API data.nasa.gov | Last Updated 2018-07-19T16:15:24.000Z
NASA's exploration and scientific missions will produce terabytes of information. As NASA enters a new phase of space exploration, managing large amounts of scientific and operational data will become even more challenging. Robots conducting planetary exploration will produce data for selection and preparation of exploration sites. Robots and space probes will collect scientific data to improve understanding of the solar system. Satellites in low Earth orbit will collect data for monitoring changes in the Earth's atmosphere and surface environment. Key challenges for all these missions are understanding and summarizing what data have been collected and using this knowledge to improve data access. TRACLabs and CMU propose to develop context aware image manipulation software for managing data collected remotely during NASA missions. This software will filter and search large image archives using the temporal and spatial characteristics of images, and the robotic, instrument, and environmental conditions when images were taken. It also will implement techniques for finding which images show a terrain feature specified by the user. In Phase II we will implement this software and evaluate its effectiveness for NASA missions. At the end of Phase II, context aware image manipulation software at TRL 5-6 will be delivered to NASA.