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In the event of a fire aboard the Orion Spacecraft, the Portable Fire Extinguisher (PFE) can introduce up to three pounds of water into the cabin to extinguish a fire. A filter was needed to work in conjunction with the Orion Fire Safety System (OFSS) to filter water out of the cabin atmosphere after dispersal from the PFE. Airflow introduced to the smoke filter of the OFSS must be dry and free of large particulates for the sorbent material to effectively extract smoke generated by a fire. These moisture and particulate concerns prompted a re-design of the original filter, especially a filter that could be tested in Earth’s gravity and yielding results that would transfer to a microgravity environment. The newly designed filter uses a multi-phase flow separation method that allows the airflow to develop fully in a helical flow path. This flow path resides within a wicking material used to separate the liquid from the gas (air) while also trapping particulate matter. Helical flow paths implemented in the filter impart a centrifugal force upon the incoming gas/liquid mixture that develops an asymmetric liquid film on the inner contour of the helix. Upon active airflow, the larger water droplets are inertially forced into the inner contour flow path wall. The flow path walls are made from a wicking material, and all liquid film and liquid droplets that are inertially deposited onto the walls are adsorbed into the filter material. The resulting output flow from the filter is 100% gas. The Corkscrew Filter has a technology readiness level (TRL) of 5 (component and/or breadboard validation in relevant environment) and is now available for patent licensing. Please note that NASA does not manufacture products itself for commercial sale.

NASA’s Carbon Capture Filter was designed to trap solid carbon dust through a variety of mechanisms. These include inertial separation, flow recirculation, flow tortuosity, media filtration, and quenching of hot particles or of precursor particles from pyrolysis. The filter uses a custom-designed housing to produce a strong and large recirculating pattern to remove dust through inertial forces and confine it into a large collection cup, which is enshrouded in a cold trap (using a thermoelectric cooler) to thermally induce precipitation of the solid carbon. The flow then passes through a single stage baffle and tube filters before exiting through the outlet at the top of the housing. During operations, gaseous carbon-containing streams enter the filter via an inlet tube at the top of the housing. The inlet tube extends down towards the bottom of the collection cup, where the high-speed stream meets a sudden perpendicular bottom wall, inducing a stagnation flow. Large particles inertially separate from the flow and impinge onto the bottom wall. The partial enclosure of the collection cup (aside from a small slit connecting it to the upper chamber) causes a recirculation bubble to form, increasing the residence time of the stream. The vortical motion of the recirculation bubble causes the large particles to spin outwards towards the walls of the collection cup. The collection cup is cooled to quench the carbon particles, causing them to precipitate out and collect on the walls of the cup. The extended residence time caused by the recirculating flow further quenches the stream. Only small particles that are entrained sufficiently by the flow make it through the slit between the collection cup and upper chamber. On the top wall of the upper chamber, an array of tubular filters collects the remaining particles before the gaseous stream exits the system. NASA’s Carbon Capture Filter has been prototyped and undergone initial testing with simulant dust, yielding promising results. The invention is available for licensing to industry.

This concept presents a new statistical likelihood function and Bayesian analysis update for non-standard measurement types that rely on associations between observed and cataloged features. These measurement types inherently contain non-standard errors that standard techniques, such as the Kalman filter, make no effort to model, and this mismodeling can lead to filter instability and degraded performance. Vision-based navigation methods utilizing the Kalman filter involve a preprocessing step to identify features within an image by referencing a known catalog. However, errors in this pre-processing can cause navigation failures. AFP offers a new approach, processing points generated by features themselves without requiring identification. Points such as range or bearing are directly processed by AFP. Operating on finite set statistics principles, AFP treats data as sets rather than individual features. This enables simultaneous tracking of multiple targets without feature labeling. Unlike the sequential processing of the Kalman filter, AFP processes updates in parallel, independently scoring each output based on rigorous mathematical functions. This parallel processing ensures robust navigation updates in dynamic environments, and without requiring an identification algorithm upstream of the filter. Computational simulations conducted at Johnson Space Center demonstrate that AFP's performance matches or exceeds that of the ideal Kalman filter, even under non-ideal conditions. Anonymous Feature Processing for Enhanced Navigation is at a technology readiness level (TRL) 4 (component and/or breadboard validation in laboratory environment) and is now available for patent licensing. Please note that NASA does not manufacture products itself for commercial sale.

This NASA technology transforms a conventional infrared (IR) imaging system into a multi-wavelength imaging pyrometer using a tunable optical filter. The actively tunable optical filter is based on an exotic phase-change material (PCM) which exhibits a large reversible refractive index shift through an applied energetic stimulus. This change is non-volatile, and no additional energy is required to maintain its state once set. The filter is placed between the scene and the imaging sensor and switched between user selected center-wavelengths to create a series of single-wavelength, monochromatic, two-dimensional images. At the pixel level, the intensity values of these monochromatic images represent the wavelength-dependent, blackbody energy emitted by the object due to its temperature. Ratioing the measured spectral irradiance for each wavelength yields emissivity-independent temperature data at each pixel. The filter’s Center Wavelength (CWL) and Full Width Half Maximum (FWHM), which are related to the quality factor (Q) of the filter, are actively tunable on the order of nanoseconds-microseconds (GHz-MHz). This behavior is electronically controlled and can be operated time-sequentially (on a nanosecond time scale) in the control electronics, a capability not possible with conventional optical filtering technologies.