System and Method for Fluid Dynamic Mass Gauging

The capacitive micro-gravity fluid mass gauge with spatial regularization is a sensor that can be outfitted to propellant vessels and can provide a determination of the mass of liquid and gas inside the vessel volume with a determinable level of accuracy. The sensor consists of 1) a number of discrete electrodes that are installed to the inner surface of the vessel wall, 2) signal generating, digitizing, signal conditioning, and general support (e.g., power supply) electronics, 3) electrical connections between the electrodes and the electronics, and 4) the algorithm used to turn the set of capacitance measurements (i.e., the capacitance matrix) into a volume fraction. The electronics generate and apply a sinusoid to a single electrode, and then the electronics measure the charge on all other electrodes. Capacitance is simply the charge divided by the voltage. This is repeated for all electrodes, without repeating duplicates. For a vessel with a fixed volume, the volume fraction can be converted to the mass fraction using the Ideal Gas Law so long as the fluid constituents, temperature, and pressure are known.

The MOD platform technology represents a small, lightweight, and reproducible in vitro drug screening model that could inexpensively mimic different mammalian tissues for a multitude of applications. The technology is automated and imposes minimal demands for resources (power, analytes, and fluids). The MOD technology uses titanium isopropoxide to bond a microscale support to a substrate and uses biopatterning and 3D tissue bioprinting on a microfluidic microchip to eliminate variations in local seeding density while minimizing selection pressure. With the MOD, pharmaceutical companies can test more candidates and concentrate on those with more promise therefore, reducing R&D overall cost. This innovation overcomes major disadvantages of conventional in vitro and in vivo experimentation for purposes of investigating effects of medicines, toxins, and possibly other foreign substances. For example, the MOD platform technology could host life-like miniature assemblies of human cells and the effects observed in tests performed could potentially be extrapolated more readily to humans than could effects observed in conventional in vivo cell cultures, making it possible to reduce or eliminate experimentation on animals. The automated NASA developed technology with minimal footprint and power requirements, micro-volumes of fluids and waste, high throughput and parallel analyses on the same chip, could advance the research and development for new drugs and materials.

Axial force is a key parameter for many aeroscience R&D applications. Axial force is the dominant component used to measure aircraft drag (for fuel efficiency purposes) and provides important control information (such as vehicle deceleration rate). Integration of Axial force measurement into this design enables a direct measure of the drag force, while simultaneously providing a fluid flow path for powered simulation in wind tunnel testing. Current state-of-the art alternatives (i.e., flow-through balances without axial force) either require investigators to infer the drag force by integrating pressure taps on the test article (which further increases axial force measurement uncertainty) or run a redundant, second wind tunnel entry with a standard six-component balance without the flow-through capability (which is not desirable because they are expensive, time consuming, and impede efficiency). While NASA’s flow-through transducer technology could be manufactured using conventional fabrication methods, additive manufacturing is expected to be preferred as it enables relatively simple incorporation of the flow-through axial element into the design without increasing manufacturing complexity or costs.

Conventionally, the approaches of creating artificial gravity in space was envisioned as a large rotating space station that creates an inertial force that mimics the effects of a gravitational force. However, generating artificial gravity with large rotating structures poses problems, including (1) the need to mass balance the entire rotating spacecraft in order to eliminate or minimize rotational imbalance causing gyroscopic precession/nutation motions and other oscillations of the rotating spacecraft; (2) the potentially prohibitive cost, time and schedule to build such a large rotating system; (3) the need to mass balance the spacecraft in real-time so as to minimize passenger discomfort and structural stress on the spacecraft; (4) the difficulty in docking other spacecraft to the rotating spacecraft; (5) the absence or minimal presence of non-rotating structure for 0G research and industrial use; and (6) the generation of extraneous Coriolis effect on spacecraft inhabitants. The novel technology can help solve the problems referenced above and other problems by (1) providing a non-rotating space station or structure, and connecting modules that generate artificial gravity by traveling along a circular path around the non-rotating space station; (2) providing modules that are more easily built and balanced; (3) providing a stationary structure that can provide a platform for other components that do not need gravity to function; (4) providing capability to actively interrogate what levels of mass imbalance are acceptable, for use in determining operational constraints; and (5) reducing or eliminating Coriolis effect on occupants in habitation modules. The concepts of the invention are very cost-effective and allow for building a minimal initial system to produce artificial gravity at the first phases of construction, before the full structure is built. An additional benefit is that construction and assembly of new capabilities can be performed without disrupting the ongoing artificial gravity environment of the existing structure.

Typical concentration sensors, like the one initially used in the UWMS, rely on changes in electrical conductivity to measure the concentration of a solution. These measurements using conductivity are prone to voltage drift over time, leading to unreliable measurements as the sensor ages. The optical sensor developed here uses light scattering to measure the solution concentration without the issue of voltage drift. In this sensor, light from a green LED is passed into the sensor housing where it hits a first detector (i.e., a photodiode) to establish a reference of the amount of light before scattering. Simultaneously, the light from the LED scatters through the pretreat solution and then hits a second photodiode to measure the amount of light after scattering. The difference between the amount of light measured by the two detectors is used to calculate the concentration of the pretreat solution (based upon Beer’s Law). The optical concentration sensor has been demonstrated to effectively measure pretreat concentrations in both still and flowing liquid conditions and is resistant to contamination issues as necessitated by the UWMS. The optical pretreat concentration sensor is at technology readiness level (TRL) 4 (component and/or breadboard validation in laboratory environment) and is available for patent licensing.