- 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 2018-07-19T10:53:04.000Z
<p>The project will develop a system of 3D-printed connectors that can be used as a kit of parts to connect inflatable air beams to form a variety of spacecraft interior outfitting components. Examples of inflatable IVA structures that can be assembled include crew quarters, waste & hygiene compartment, crew medical restraint system, splints, science payload racks, stowage and other equipment racks, science glove box, recreational devices, other portable devices, work surfaces and other workstations, support braces, other secondary structures, etc. This inflatable technology can enable such hardware to be packaged in much smaller volumes for delivery in logistics flights or potentially to be integrated within inflatable spacecraft, increasing trade space options. Crew can also reconfigure spacecraft in-flight, using the ability to 3D-print custom connectors to redesign living spaces or create entirely new interior architectures to respond to mission developments or psychosocial needs.</p> <p>The Habitabiltiy Design Center has already prototyped scale models of inflatable crew stations and initial prototypes of a standard interface connector. These connectors have demonstrated basic capability, but are too large relative to the airbeams for pracitcal use. We have a notional reduced size connector and will use this concept as a starting point, to fabricate and test under operational inflation pressures. Pending initial success, we will fabricate various connectors to provide several linear and angled connections. This will form the basic building block for assembly of a variety of crew stations and support hardware.</p><p> </p><p>This research addresses HAT Needs Numbers 12.1.a and 12.1.b and provides steps towards several HAT-specified performance targets: Bladder Material Selection: The potentially frequent cycles of inflation and deflation experienced by IVA inflatable structures will require bladder material and seal interfaces capable of resisting puncture, tear, flex cracking, or other damage due to folding, handling, or stowage temperatures. Predictive Modeling of Deployment Dynamics: Inflation or deflation may involve imparted torques and loads that require IVA inflatable structures to be anchored to the spacecraft secondary structure prior to the initiation of inflation or deflation. Lightweight Structures and Materials Optimization to Realize Structural System Dry Mass Savings (Minimum of 20-25%) and Operational Cost Savings: The inflatable air beam and connector technology offers significant dry mass savings over traditional IVA structural materials. Structural mass savings for an individual crew quarters is expected to be in excess of 75% over ISS crew quarters.</p><p> </p><p>The intended product deliverable of this activity includes three airbeams of at least 12-inch length and no less than one each of the following: 90-degree connector, 45-degree connector, 180-degree connector, 90-degree five-airbeam connector, 60-degree three-airbeam connector. Additionally, a test report and CAD models for each connector will constitute deliverables of this activity.</p><p> </p><p>Upon completion of this initial ICA effort, we will be able to demonstrate use of the airbeams in conjunction with existing Logistics to Living Modified Cargo Transfer Bags (MCTBs) to demonstrate deployable partitions as an initial example case. This demonistration will be helpful in explaining the potential for continued investment to reduce both mass and habitability risks. We will continue to pursue research funding for further development and will also pursue options to directly engage exploration programs to generate solutions for their specific mission architectures.</p>
- 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 2018-07-19T15:54:02.000Z
Automated detection of land cover changes between multitemporal images (i.e., images captured at different times) has long been a goal of the remote sensing discipline. Most technology in this area has focused on methods for detecting and identifying land cover or surface object changes in two or more images, but precise co-registration of images remains a key challenge. In fact, image-to-image registration and image-based change detection are intricately related, as the success of conducting both relies on the precision of the other; software that supports these functions should do so in an integrative manner. Image registration is the key factor influencing the success of detecting land cover changes at or near pixel scale. We will develop tools in the form of a "software development kit" (SDK) specifically optimized for precise co-registration of two or more images with minimal user interaction, with the primary motivation to enable change detection algorithms to focus on salient changes rather than highlight image registration errors. The SDK will be available to NASA at no cost, after which we will build user applications based on the SDK for commercial offering.
- 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 2018-07-19T07:44:42.000Z
Monofilament Vaporization Propulsion (MVP) is an innovative new propulsion technology targeted at secondary payload applications. The approach with MVP, rather than using exotic propellants to achieve maximum specific impulse and system performance, is to use an inexpensive, inert, solid propellant. This enables the use of a propulsion system on lower budget missions by lowering the unit cost (no valves or pressure vessels), and minimizes range safety expenses. By using a commercially available, space rated polymer as propellant, MVP overcomes potential issues associated with liquid propellants such as freezing, over-pressurization, degradation (of tank wall and/or propellant itself), and cg perturbations due to sloshing. As a result, MVP's standalone risk to the primary payload is no greater than that of a CubeSat not equipped with propulsion. MVP harnesses technology used in 3D printing applications to feed propellant into proven electrothermal propulsion technology developed by CU Aerospace. To date, MVP has demonstrated a continuous 105 seconds specific impulse with 20 W input power, with 107 seconds peak. Phase II performance is expected to exceed 130 seconds. This should provide 900 N-s total impulse with a 1U (10 cm x 10 cm x 10 cm) system, attributable to the high storage density and permissible thin walled construction. A 4 kg, 3U CubeSat equipped with MVP could achieve 250 m/s Delta-V while expending less than 25 W during operation. CU Aerospace will design, fabricate, and deliver a 1U MVP system to NASA at the end of the Phase II program.
- API data.nasa.gov | Last Updated 2018-07-19T05:00:51.000Z
NASA's International Halley Watch (IHW) has created a Comet Halley Archive. The collection of data spans the full wavelength range as submitted by scientists to the IHW. The observations belong to one of the following Disciplines: Amateur, Astrometry, Infrared Studies, Large-Scale Phenomena, Meteor Studies, Near-Nucleus Studies, Photometry and Polarimetry, Radio Studies, and Spectroscopy and Spectrophotometry. The data collected by these nine disciplines were augmented by Spacecraft measurements. The data were submitted to IHW, but the evaluation and selection for the Archive has been the primary responsibility of the Discipline Specialist Teams for each network in cooperation with the Lead Center. The data from the Infrared Spectroscopy subnetwork contains 75 spectra of Halley and 9 data used for calibration. The calibration spectra had as targets stars (HYA 106, BETA LEP) and a planet (MARS). The data covers dates from 1985 October 29 through 1986 May 24.