Browse Topic: Microgravity
Measuring fluid mass in microgravity, where fluid behavior is dominated by fluid properties, is a challenging problem. To address this problem engineers at NASA are developing a capacitance-based, mass-fraction gauge for vessels containing two-phase fluids. The vessel volume is enclosed with an array of electrodes, and a unique set of capacitance measurements of the enclosed volume are made between the electrodes. The capacitance measurements are scaled with appropriate weighting factors derived from Laplace’s Equation to compensate for the highly non-uniform electric fields inside the measurement volume and achieve a greater level of mass fraction accuracy
The ForgeStar® program, from U.K.-based Space Forge, aims to harness the unique environment of space to create ultra-pure materials that cannot be replicated on Earth. The key opportunities lie in producing high-performance semiconductors and super-alloys with fewer defects and superior properties, thanks to the low-gravity and vacuum conditions of space. Space Forge's ForgeStar satellites will be used to produce advanced materials such as alloys, proteins and semiconductors in the ultra-vacuum and microgravity conditions of space. Manufacturing in low Earth orbit (LEO) has huge potential across sectors from medicine to advanced electronics. Two examples - high frequency amplifiers and super alloys - that Space Forge is focused are described in the next two paragraphs
We are in the midst of a golden age of space travel with the upcoming launch of multiple reusable heavy lift rockets. These new craft will increase deliverable mass to LEO and decrease delivery costs. These rockets are essential to replacing the ISS with commercial space stations in the coming decade. These new commercial stations will enable the creation of in-space factories that leverage microgravity to improve products for use on Earth. Large-scale 3D bioprinting is one technology that will benefit from microgravity and has the potential to address the organ shortage and overreliance on animal models for drug discovery and testing
Recent experiments by a team from the West Virginia University focused on how a weightless microgravity environment affects 3D printing using titania foam, a material with potential applications ranging from UV blocking to water purification. ACS Applied Materials and Interfaces published their findings
For both space tourism and space exploration, there is an interest in generating artificial gravity in space for entertainment, recreational, and scientific purposes, as well as to counter the health concerns of extended exposure to a microgravity environment. NASA Ames Research Center has developed a novel technology — a system and approach for creating artificial gravity using a non-rotating spacecraft with connected moving modules, which can be used for habitation and other purposes
NASA asks hard questions: What’s it like on the Moon? Has there been life on Mars? How did the first stars form? Finding these big answers often means first solving a series of smaller but equally vexing questions. For example, how does prolonged weightlessness change the way the brain controls muscles? How does the brain control muscles? Before sending humans on the long journey to Mars, NASA wants to better understand the effects the trip will have on astronauts. Now a company that helped the space agency try to solve these questions is helping others find answers as exciting as any NASA discovery
A person who is inactive for an extended period of time (such as when they have a long illness) loses strength as well as muscle and bone mass. Astronauts on the International Space Station (ISS) face similar risks because bones and muscles begin to atrophy in the absence of gravity. Resistive exercise, where the musculoskeletal system bears weight, has been shown to mitigate these effects. But just lifting weights, as we do on Earth, does not work without gravity
Numerical prediction of a confined, co-flowing, laminar jet diffusion flame has been investigated under sinusoidal “g-jitter” to describe the flame structure; this type of flame-body force interaction is typical of a microgravity environment such as in the spacecraft. We introduced g-jitter in the direction orthogonal to the fuel and air inflow. We show that the lower frequencies (0.1-0.5 Hz) of sinusoidal g-jitter significantly affected the flame geometry and behavior. The majority of the flame structure was found to oscillate directly in response to the imposed g-jitter. It has also been observed that nonlinearity in the response behaviors is more prominent in the reaction zone of the flame
Experiments of flame-spread of fuel droplets have been performed in microgravity actively. However, the experiment has limitation in the number of droplets due to relatively short microgravity durations in the ground based facilities. It is difficult to conduct flame spread experiments of large scale droplet clouds in microgravity. This study conducted simulation of flame-spread behavior in randomly distributed large-scale droplet clouds by using a percolation approach, in order to make a theoretical link the gap between droplet combustion experiments and spray combustion phenomenon with considering two-droplet interaction. Droplets are arranged at lattice points in 2D lattice. The occurrence probability of group combustion (OPGC) is calculated as a function of the mean droplet spacing (S/d0)m. The (S/d0)m for 0.5 OPGC is defined as the critical mean droplet spacing (S/d0)critical, which separates the droplet cloud into two groups if the lattice size becomes infinity; relatively dense
NASA's Langley Research Center has developed a method and apparatus to be used for cell culture that combines the effects of microgravity and low-dose radiation. The technology has been developed to simulate the effects of microgravity and chronic radiation exposure to cell culture experiments conducted on the International Space Station (ISS
This technology allows one to test small-body surface mobility and sampling systems in the laboratory. It is capable of simulating a microgravity environment with relevant terrain. The magnitude of the gravity, the terrain properties, and the surface system being tested are all easily modified to allow for a broad range of experimental setups
To train astronauts to live and work in the weightless environment on the International Space Station, NASA employs a number of techniques and facilities that simulate microgravity. Engineers at the NASA Johnson Space Center (JSC) have developed a new system called the Active Response Gravity Offload System (ARGOS) that provides a simulated reduced gravity environment within a confined interior volume for astronauts to move about and/or equipment to be moved about as if they were in a different gravity field. Each astronaut/item is connected to an overhead crane system that senses their actions (walking or jumping, for example) and then lifts, moves, and descends them as if they had performed the action in a specified reduced gravity
Supplemental oxygen delivery systems are vital to provide a critical life support respiratory function. Whether they are used for patients suffering from lung diseases or other illnesses, or astronauts donning an oxygen mask during a toxic spill or fire on a spacecraft, lightweight and portable oxygen delivery systems are in high demand. A lightweight portable oxygen concentrator was developed that can produce 1 to 6 lpm of pulse oxygen in a noiseless system that can be worn on the user’s hip or in a shoulder sling
In the beginning, safety trumped comfort in spacecraft designs for human space travel. Early space capsules were small and had a seat-driven design in which most of the flight activities were performed while the crew was strapped into their seats. NASA devoted more attention to understanding how a spacecraft could provide comfort as well as safety and function. One of the first things NASA examined was the neutral body posture (NBP), or the posture the human body naturally assumes in microgravity
The microgravity conditions of space travel create unique physiological demands on the astronauts’ skeletal structures, resulting in a reduction in bone strength from restructuring of the micro-architecture and loss of key minerals. An ultrasound system was developed that is capable of quantitatively correlating a series of measurement parameters to the physiology. The Nautilus transducer is a spiral-wrapped ultrasound transducer fabricated from piezoelectric Mn:PIN-PMN-PT single crystal that uses micromachining to take advantage of unique resonance modes within the crystal. The combination of integration of a single crystal and use of multiple resonances provided a bandwidth superior to commercial devices with the capacity for high sensitivity
Robust, high-temperature containment cartridges are needed for processing materials science experiments in microgravity. In general, the refractory metals (Nb, Ta, Mo, W, Re) possess the chemical inertness and high melting temperatures desired. Of these materials, niobium and tantalum alloys have been the materials of choice due to their low ductile to brittle transition temperatures, which allow deep-draw forming into cylindrical shapes. The high cost of tantalum and niobium, along with the desire for cartridges resistant to molten zinc and usable to 1,500 °C, demonstrates the need for alternative cartridge materials. Two candidate materials are molybdenum and tungsten alloys. Both have high melting temperatures and cost an order of magnitude less than tantalum and niobium
A recent innovation has made manipulation of hazardous laboratory reagents in microgravity easier, thus enabling even more scientific research to be performed on the International Space Station (ISS). Prior to this innovation, moving fluids from container to container was performed only under conditions of redundant and physically separate layers of containment. This design paradigm restricts access to — and direct manipulation of — fluids in microgravity conditions
Inspection of the International Space Station and other manmade objects in space is difficult because of the microgravity environment. Robots are a promising approach to accomplish these inspection tasks and later repairs, but must be able to maneuver across the surfaces. Because there is no gravity, the robot is at high risk of floating away, necessitating grippers that can adhere to the surface and resist the forces and torques of inspecting and moving on the structure
Back pain and injury are recognized risks that can affect the well-being and performance of crewmembers during missions, as well as their long-term health. Spine elongation is a documented effect of microgravity, back pain is a common occurrence in early flight, and the post-flight incidence of spinal injury is higher than the population average. These observations suggest that spinal unloading results in a transition to a new set point for the spine, and causes discomfort and an increased risk of injury
NASA has long recognized the difficulty in providing emergency medical care to astronauts in space. Many aspects of space travel make medical care inherently difficult, and sufficient storage space for medical equipment severely limits the ability to carry a full complement of diagnostic and therapeutic equipment onboard. The Microgravity Compatible Medical Suction Device (MCMSD) enables aspiration and containment of bodily fluids and vomitus, while preventing the transmission of infectious agents
The deleterious effects of microgravity are undeniable: reduced bone mineral density, muscle atrophy, vascular remodeling, etc. These health issues may derive from both systemic factors, and from direct alterations to intracellular components and in the local microenvironment around cells. To understand the biological mechanisms at play, detailed studies have been performed in spaceflight. However, because experiments on the International Space Station (ISS) can be prohibitively expensive, clinostats are an alternative ground-based analogue for cellular studies. Clinostats “randomize” the orientation of gravity with respect to the cell fixed-frame, thereby simulating microgravity by eliminating a preferential gravity direction
The ability to monitor and detect microorganism contamination/infection is important for long space voyages, in order to maintain a clean environment not only for the health of the astronauts, but also for electronics and structural materials. Technologies based upon the polymerase chain reaction (PCR) method have proven to be faster and more sensitive than traditional methods in diagnosis of microorganisms. The real-time PCR technique has been used on the ground to detect microorganisms in the samples collected on the International Space Station (ISS). However, the ability of using PCR to detect infectious agents rapidly and specifically in space is currently unavailable. The major technological blockade to the use of PCR in space is the lack of a hazard-free and microgravity compatible hardware for RNA/DNA isolation
Preliminary data was recently provided for a reaction sphere prototype on NASA’s zero-gravity parabolic flight vehicle. Gyroscope telemetry indicates that reaction spheres were successfully commanded at 10- to 20-ms pulses during a handful of parabolas in each flight. This is the first publicly disclosed validation of a freely rotating reaction sphere in a standalone compact package. At dimensions of
Space motion sickness (SMS) commonly experienced by astronauts during a space mission often requires treatment with medication. However, exposure to a microgravity environment results in a myriad of physiological changes that alter bioavailability. In particular, studies indicate that the bioavailability of oral scopolamine (SCOP) is decreased during spaceflight. Although altered gastrointestinal function, including delayed gastric emptying, appears to contribute to decreased bioavailability of oral medications, other factors typical of spaceflight may influence the pharmacokinetics of medications administered via a variety of other non-parenteral routes
A concept for a unique zero-g condensing heat exchanger that has an integral ozone-generating capacity has been conceived. This design will contribute to the control of metabolic water vapor in the air, and also provide disinfection of the resultant condensate, and the disinfection of the air stream that flows through the condensing heat exchanger
Propellant mass gauging in microgravity has posed a challenge for decades. Various methods have been applied, including ultrasonic, capacitance probes, point level sensors, thermal detectors (thermistors, thermocouples, etc.), Michelson interferometry, and nuclear devices. All have problems in terms of how to provide accurate measurements irrespective of the fluid orientation in the tank
In the beginning, safety outweighed comfort in spacecraft designs for human space travel. Capsules like Gemini and Apollo were small, and most of the flight activities were performed while the crew was strapped to their seats. Later, NASA devoted more attention to understanding how a spacecraft could provide comfort as well as safety and function to astronauts. NASA examined the neutral body posture (NBP), or the posture the human body naturally assumes in microgravity
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