materials and coatings
PICA being tested in Arcjet Facility
Creating Low Density Flexible Ablative Materials
The low density flexible ablator can be deployed by mechanical mechanisms or by inflation and is comparable in performance to its rigid counterparts of the same density and composition. Recent testing in excess of 400W/cm2 demonstrated that the TPS char has good structural integrity and retains similar flexibility to the virgin material, there by eliminating potential failure due to fluttering and internal stress buildup as a result of pyrolysis and shrinkage of the system. These flexible ablators can operate at heating regimes where state of the art flexible TPS (non-ablative) will not survive. Flexible ablators enable and improve many missions including (1) hypersonic inflatable aerodynamic decelerators or other deployed concepts delivering large payload to Mars and (2) replacing rigid TPS materials there by reducing design complexity associated with rigid TPS materials resulting in reduced TPS costs.
materials and coatings
Reentry Vehicles
New Resin Systems for Thermal Protection Materials
This method produces a low density ablator similar to Phenolic Impregnated Carbon Ablator (PICA) using a cyanate ester and phthalonitrile resin system, rather than the heritage phenolic resin. Cyanate ester resin systems can be cured in a carbon matrix and generate high surface area structure within the carbon fibers. This helps to reduce the thermal conductivity of the material which is one of the key requirements of thermal protection system (TPS) materials. The material has densities ranging from 0.2 to .35 grams per cubic centimeter. NASA has successfully processed the cyanate ester and phthalonitrile resins with a morphology similar to that of the phenolic phase in PICA, but with more advanced properties such as high char stability, high char yield, and high thermal stability. This new generation of TPS materials has the same microstructure as heritage PICA, but improved characteristics of PICA such as increased char yield, increased char stability, increased thermal stability and increased glass transition temperature.
Hubble Sees Spiral in Serpens; Credit: ESA/Hubble & NASA,
SpaceCube Demonstration Platform
The HST SM4 SpaceCube flight spare was modified to create an experiment called the SpaceCube Demonstration Platform (SC DP) for use on the MISSE7 Space Station payload (in collaboration with NRL). It is designed to serve as an on-orbit platform for demonstrating advanced fault tolerance technologies. With the use of Xilinx commercial Virtex4 FX60 FPGAs, the fault tolerant framework allows the system to recover from radiation upsets that occur in the rad-soft parts (Virtex4 FPGA logic, embedded PPCs in Virtex4 FPGAs, SDRAM and Flash), the C&DH system that runs simultaneously on both Virtex4 FPGAs that uses a robust telemetry packet structure, checksums, and the rad-hard service FPGA to validate incoming telemetry. The ability to be reconfigured from the ground while in orbit is a novel benefit, as well as is the onboard compression capabilities that allow compressed files from the ground to be uploaded to the SpaceCube.
materials and coatings
Orion re-entry in to earth's atmosphere
Multifunctional Ablative Thermal Protection System
The initial compression pad design for Orion was complex and limited to Earth orbit return missions, such as the 2014 Exploration Flight Test-1 (EFT-1). The 2-D carbon phenolic material used for EFT-1 has relatively low interlaminar strength and requires a metallic sheer insert to handle structural loads. There are few options for materials that can meet the load demands of lunar return missions due to performance or part-size limitations. The 3DMAT material is a woven fiber preform fully densified with cyanate ester resin. It produces a large composite with significant structural capabilities and the ability to withstand high aerothermal heating environments on its outer surface while keeping the inner surface cool and protected from the aerothermal heating. The robustness of the 3DMAT material is derived from high fiber volume (>56%), 3-D-orthoganol architecture, and low porosity (0.5%). Orion has adopted 3DMAT for all future MPCV missions, including EM-1 schedule to launch in 2018.
materials and coatings
A New Family of Low-Density, Flexible Ablators
The invention provides a family of low density, flexible ablators comprising of a flexible fibrous substrate and a polymer resin. The flexible ablators can withstand a wide range of heating rates (40-540 Watts/cm2) with the upper limit of survivable heat flux being comparable to the survivable heat flux for rigid ablators, such as PICA and Avcoat. The amount and composition of polymer resin can be readily tailored to specific mission requirements. The material can be manufactured via a monolithic approach using versatile manufacturing methods to produce large area heat shields, which provides a material with fewer seams or gaps. The goals of the work are primarily twofold: (i) to develop flexible, ablative Thermal Protection System (TPS) material on a large, blunt shape body which provides aerodynamic drag during hypervelocity atmospheric entry or re-entry, without perishing from heating by the bow shock wave that envelopes the body; and (ii) to provide a relatively inexpensive TPS material that can be bonded to a substrate, that is unaffected by deflections, by differences in thermal expansion or by contraction of a TPS shield, and that is suitable for windward and leeward surfaces of conventional robotic and human entry vehicles that would otherwise employ a rigid TPS shield. This technology produces large areas of heat shields that can be relatively easily attached on the exterior of spacecraft.
information technology and software
Hubble Spies Charming Spiral Galaxy Bursting with Stars
Radiation Hardened 10BASE-T Ethernet Physical Interface
Currently there is no radiation hardened Ethernet interface device/circuit available commercially. In this Ethernet solution, the portion of the PHY in the FPGA is responsible for meeting the IEEE 802.3 protocol, decoding received packets and link pulses, and encoding transmitted data packets. The decoded payload data is sent to a user interface internal to the FPGA which sends data for transmission back to the FPGA PHY. The transmit portion is composed of two AD844 op amps from Analog Devices with appropriate filtering. The receive portion is composed of a transformer, an Aeroflex Low-Voltage Differential Multi-drop device, and appropriate filtering.
SMART Solar Sail
SMART Solar Sail
The SMART solar sail includes a reflective film stretched among nodes of a SMART space frame made partly of nanotubule struts. A microelectromechanical system (MEMS) at each vertex of the frame spools and unspools nanotubule struts between itself and neighboring nodes to vary the shape of the frame. The MEMSs is linked, either wirelessly or by thin wires within the struts, to an evolvable neural software system (ENSS) that controls the MEMSs to reconfigure the sail as needed. The solar sail is highly deformable from an initially highly compressed configuration, yet also capable of enabling very fine maneuvering of the spacecraft by means of small sail-surface deformations. The SMART Solar Sail is connected to the main body of the spacecraft by a SMART multi-tether structure, which includes MEMS actuators like those of the frame plus tethers in the form of longer versions of the struts in the frame.
materials and coatings
Front Image ARC-16132-1
Surface Densification Of Phenolic Impregnated Carbon Ablator (PICA)
The graded Thermal Protection System (TPS) offers a lower density than comparable state-of-the-art TPS systems operating at similar maximum heating conditions. This approach is straight forward in terms of processing and surface-treatment application and can be applied to machine PICA materials without having an effect on the final tolerance. The process results in increased usability and handling since standard uncoated PICA is relatively weak. Surface-densified PICA provides an approach for improvements in the robustness for the baseline CEV heat shield. A graded approach eliminates the need for joints and/or bonding agents between material plies. PICA surface densification offers robust mechanical protection against transit damage, handling damage, and in-flight object damage.
information technology and software
Automatic Extraction of Planetary Image Features
Automatic Extraction of Planetary Image Features and Multi-Sensor Image Registration
NASAs Goddard Space Flight Centers method for the extraction of Lunar data and/or planetary features is a method developed to extract Lunar features based on the combination of several image processing techniques. The technology was developed to register images from multiple sensors and extract features from images in low-contrast and uneven illumination conditions. The image processing and registration techniques can include, but is not limited to, a watershed segmentation, marked point processes, graph cut algorithms, wavelet transforms, multiple birth and death algorithms and/or the generalized Hough Transform.
information technology and software
Tycho Crater's Peak; Credit: NASA Goddard/Arizona State University
Space Link Extension Return Channel Frames (SLE-RCF) Software Library
The Space Link Extension Return Channel Frames (SLE-RCF) software library helps to monitor the health and safety of spacecraft by enabling space agency ground support and mission control centers to develop standardized and interoperable mission control applications for space telemetry data. The software library eliminates the need for missions to implement custom data communication designs to communicate with any ground station. The two main tasks accomplished via the SLE-RCF software library are processing user requests and receiving data from ground stations and ground support assets. The software library contains three layers: -SLE (Space Link Extension) for the abstract workings of the protocol -DEL (Decoding and Encoding Layer) to decode and encode the abstract messages used by the SLE layer -TML (Transport Mapping Layer) to transfer the encoded messages via some underlying transport layer protocol, such as as the transmission control protocol (TCP) The library accepts configuration or SLE-RCF directives from the user and responds accordingly. Incoming data, both telemetry frames and status messages, are processed and the appropriate callback routines are triggered by the library.
Stay up to date, follow NASA's Technology Transfer Program on:
facebook twitter linkedin youtube
Facebook Logo Twitter Logo Linkedin Logo Youtube Logo