We report a highly aligned multiwalled carbon nanotube (MWCNT) tape with a P(VDF-TrFE) matrix that is mechanically robust and has excellent piezoelectric properties for sensor applications, including, but not limited to vibration gyroscopes and accelerometers. The tapes were tested for piezoelectric response via hysteresis measurements and d33 measurements. It was found that 10 weight percent P(VDF-TrFE) in a solution of DMSO resulted in increased values of dielectric constant, piezoelectric coefficient and mechanical properties. The d33 value for the CNT/P(VDF-TrFE) was 70 pm/V, which is approximately twice that for pure P(VDF-TrFE) film. Adding 10 weight percent BaTiO3 nanoparticles (100nm) increased the piezoelectric d33 value to 81 pm/V. These results are attributed to Maxwell-Wagner-Sillars polarization. This material has a tensile strength of 120 MPa and a Young’s modulus of 17.8 GPa. Keywords: Barium titanate, carbon nanotube, piezoelectricity, P(VDF-TrFE), sensors, strength.
An example is considered (clock riddle) which demonstrates that opposite results are obtained for the length of an object depending on whether FitzGerald-Lorentz contraction (FLC) is assumed or instead the determination is based on the elapsed time required for a light pulse to traverse between its endpoints. This lack of internal consistency in relativity theory is traced to an undeclared assumption Einstein made regarding a normalization factor appearing in his original derivation of the Lorentz transformation (LT). If the empirical relationship between clock rates employed in the methodology of the Global Positioning System (GPS) is used to fix the value of this factor, an alternative Lorentz transformation (ALT) is shown to result that removes the above inconsistency, while still satisfying Einstein's two postulates of relativity and remaining compatible with Einstein's relativistic velocity transformation (VT) as well. Keywords: Alternative Lorentz transformation (ALT), global positioning system (GPS), Lorentz transformation (LT), postulates of special relativity, velocity transformation (VT).
Recent efforts in space exploration have focused on budget solutions for monitoring Earth’s climate and astrophysics. Implementing such a satellite requires thermal design in order to maintain the scientific instruments and bus components within their ideal operating temperatures. This paper outlines the thermal system’s engineering design and thermal analysis for a High Usability Host Spacecraft. Preliminary thermal engineering results suggest that the High Usability Host Spacecraft concept proposed herein is viable for low-cost scientific instrumentation satellite based missions. Keywords: NX space systems thermal, satellite, spacecraft, systems engineering, thermal control.
It is assumed that cosmic rays and other high-energy particles of extraterrestrial origin can be produced by first-order Fermi diffusive shock acceleration in plasma up to 5x1019 eV, the point where they interact with the cosmic microwave background (CMB). First-order Fermi shock acceleration is due to a supersonic shock with a Mach number dependent on the index (or logarithmic slope) of the shock-induced power-law spectrum. The local all-particle interstellar cosmic-ray spectrum can be obtained from the solution of a Fredholm integral equation in rigidity, yielding both the “knee” and the “ankle” of the primary spectrum. The effect of the maximum galactic acceleration mechanism at high energies near the ankle is to increase the relative number of heavy nuclei relative to protons. Multiple cutoffs of heavier nuclei due to interactions with the CMB have the opposite effect just below the Greisen-Zatsepin-Kuz’min (GZK) cutoff, resulting in fluxes enriched in protons. Earthward-directed supersonic coronal mass ejections are responsible for the great bulk of high-energy solarparticle events because of diffusive shock acceleration in the heliosphere. Keywords: Air shower data, cosmic rays, GZK cutoff, Monte Carlo solution to integral equations, plasma, Shock acceleration, solar modulation, the local interstellar spectrum.
Thin film CdTe/CdS has long been regarded as one promising choice for the development of cost-effective and reliable solar cells. High efficiency has been achieved in CdTe/CdS heterojunction structure in laboratory and current techniques for CdTe/CdS solar cells gradually step toward commercialization. Advances in different process of materials depositions and configurations of CdTe/CdS films with applications in solar cells are presented in this work. We review some recent patents and scientific papers that show innovated process to improve the properties of the CdTe/CdS cells. This improvement would have as a result the development of new technologies that may allow the production of CdTe/CdS cells at large scale. Keywords: CdTe, CdS, CdTe/CdS Solar cells, close-space sublimation, sputtering, chemical bath deposition, electrochemical bath deposition, thin oxide-glass.
Recent new highly precise experimental observations, achieved with the help of the tightly synchronized clocks of the GPS, reveal very clearly that real space, ruling the inertial motion of matter and the propagation of light, is moving round earth and round the sun according to a Keplerian velocity field, consistent with the local main astronomical motions. Such real space is well at hand in the Quantum Field Theory (QFT), underlying the Standard Elementary Particle Model (SEPM). The QFT entails the idea that space is filled up with the Higgs condensate (HC), a Bose-Einstein condensate of the zero spin Higgs bosons and a very powerfull quantum space (QS), stable up to 1015 degrees Kelvin. According to QFT, likewise the superconducting condensate confines magnetic fields by the Meissner effect, making them short-range and giving inertial mass to the photons, the HC confines the matter fields by the Higgs Mechanism, giving mass to the elementary particles, that is, providing them with mechanical properties. This lets clear that the HC rules the inertial motion of matter and the propagation of light and hence is the locally ultimate reference for rest and for motion of matter and light. Moreover, likewise superconductors, develop a macroscopic velocity field of the superconducting condensate (screening currents), expelling magnetic fields, the HC too may develop a macroscopic velocity field of the condensate (screening currents) in the form of a Keplerian velocity field of the QS, consistent with the local main astronomical motions, round each matter body throughout the universe. The present work demonstrates that this Keplerian velocity field of the QS appropriately induces the observed gravitational dynamics on earth, in the solar system as well as the galactic gravitational dynamics without the need of dark matter. This Keplerian velocity field is the quintessence of the gravitational fields. It thrusts and compresses the matter fields into compact bodies. It also provides a dominant antigravitation mechanism accelerating the expansion of the universe. It finally is shown that this QS-dynamics correctly and appropriately gives rise, in terms of simple and genuine physical effects, to all the other observed effects, caused by the gravitational fields on the propagation of light and on the rate of the clocks. Keywords: Dark Energy, dark matter, gravitational effects, gravitational fields, gravitational physics, gravity.
Successful technologies include objects, processes, and procedures that share a common theme; they are being used to generate new products that create economic growth. The foundation is the invention, but the invention is a small part of the overall effort. The pathway to success is understanding the competition, proper planning, record keeping, integrating a supply chain, understanding actual costs, intellectual property (IP), benchmarking, and timing. Additionally, there are obstacles that include financing, what to make, buy, and sell, and the division of labor i.e. recognizing who is best at what task. Over the past two decades, NASA Langley Research Center (LaRC) has developed several commercially available technologies. The approach to the commercialization of three of these inventions; Langley Research Center-Soluble Imide (LaRC-SI, Imitec Inc.), the Thin Layer Unimorph Driver (THUNDER, FACE International), and the Macrofiber Composite (MFC, Smart Material Corp.) will be described, as well as some of the lessons learned from the process. What makes these three inventions interesting is that one was created in the laboratory; another was built using the previous invention as part of its process, and the last one was created by packaging commercial-off-the-shelf (COTS) materials thereby creating a new component.
The spacecraft payload operational time (SPOT) is amongst the main critical design considerations that must be optimised and validated during the system engineering analysis of a spacecraft mission. This requirement becomes more demanding for a communication satellite mission that relies on the functionality of the payload for its operation and service delivery. The design principles and performance budgets of the payload module are based on the subsubsystems and subsystems that enable the mission to be accomplished. The SPOT constraint is tied to the spacecraft size, weight and power (SWAP) limitations, operational modes of the subsystems and orbital patterns where the system is being deployed. This paper presents a system-level multicriteria optimisation of POTs for communication satellite (ComSat) missions in low-Earth orbit (LEO). The parameter space investigation (PSI) method was utilised to accomplish the multicriteria optimisation of the payload power and spacecraft mass. In the multicriteria optimisation and vector investigation (MOVI) process, 2048 tests were performed and the PSI was conservatively designed to yield 658 pareto optimal solutions vectors; a pareto optimal solution of 37.119 W for the payload module yielded highly adaptive microsatellite (HAM) mass and power margin of 97.021 kg and 23.366 W respectively. The required maximum subsystem power consumption for the power-storing mode is 25.703 W. From the analysis, the solar array capability was calculated to deliver 116.828 W for the mission; this forms the beginning-of-life design point. The prototype design for the ComSat mission yielded a maximum POT of approximately 494 minutes for the onboard payload processing and communication (downlink and uplink). The findings promise to enhance the design of a reliable and capability-based payload module for real-time digital video and broadband media, mobile services, interactive data transfer and voice communication.
Advances in different components and configurations of fuel cells which have application in space technology are presented in this work. A review of patents related to fuel cells, from materials to systems and their interconnection with unmanned or manned space crafts, permits to evaluate the current trends in these highly efficient technologies. In fact, it should be mentioned that fuel cells found their first technological application in the early Apollo and Gemini space programs, where Alkaline and Polymer Electrolyte Fuel Cells were used as the power source. Since then, fundamental and applied research has led to highly reliable and efficient modern fuel cell systems. Keywords: Alkaline fuel cells, craft propulsion system, electronic controller, gaseous hydrogen fuel, manned craft, liquid oxygen, pressurizing tanks, propulsion system, polymer electrolyte fuel cells, regenerative fuel cells, telecommunication satellites, solid oxide fuel cells, spacecraft, space station, space vehicle fuel cell, unmanned craft, water-hydrogen mixture.
Polycrystalline CuInSe2- based thin films have exhibited very promising performance for thin film photovoltaic (PV) applications, now exceeding 20% conversion efficiencies at the laboratory scale. CuInSe2-based thin-film solar cells technology is being used for terrestrial applications, however they are considered the main competitor candidate of the traditional crystalline solar cells, to provide the electrical power needed for space applications, especially when the CuInSe2-based film deposition is considered on flexible-lightweight substrates. The overall advantages of CuInSe2-based thin-film solar cells technology include low mass and storage volume, high power, lower production cost, high radiation resistance and stability, very important criteria to fulfill when their use is considered for space applications. The best quality CuInSe2-based PV devices have been processed using high vacuum techniques. However, there is an interest in developing deposition techniques that avoid the use of high vacuum, especially when considering scale-up to industrial processing levels. Electrodeposition offers a number of advantages over high-vacuum deposition techniques, requiring a low cost equipment, allows deposition over large areas at low temperature and atmospheric pressure conditions, good control of film thickness, and it is a self-purifying process, allowing thus the use of low purity precursor materials. All these features are translated into reduction of production costs. In this paper, we described an approach to grow CuInSe2- based thin films by the electrodeposition technique onto soda-lime glass substrates with a sputtered Mo layer. We discussed some aspects of the patent “Post deposition treatments of electrodeposited CuInSe2-based thin films”, regarding the control of the chemical composition and the morphology of the film growth over rigid substrates. Finally, we discussed the advantages of using these CuInSe2-based thin films for terrestrial and space applications, and a brief review of other patents that deal with some issues regarding their deposition on flexible-lightweight substrate. Keywords: Electrodeposition, CuInSe2-based thin films, solar cells.
In this report dosimetric measurements are presented which were performed during the missions Spacelab 1, D 1, Biocosmos 8 and Biocosmos 9. Detector packages consisting of plastic nuclear track detectors, nuclear emulsions and thermoluminescence dosimeters were exposed at different locations inside and outside spacecrafts behind more or less well defined shielding thicknesses. These detector systems which supplement each other in their registration characteristic allow to record all biological relevant portions of the radiation field separately. Dose equivalents for the astronauts have been calculated from the measurements using the quality factors as defined in the old and the new recommendations of the International Commission on Radiation Protection (ICRP).
Lab-on-a-chip (LOC) systems with electrochemical sensing capability can provide real-time physiological measurements in spaceflight environments. They are easily miniaturized and integrated with existing space hardware systems. To reduce crew time during spaceflight research, the systems can be made autonomous and simple to use. Research and development of electrochemical-sensing LOC systems are still in progress for fundamental space-biology research in microgravity. Ion-selective electrodes as electrochemical sensors are miniaturized in an all-solid-state format for easier packaging and handling. The design, fabrication, and application of these sensors are discussed, with examples from those developed at the Physiological Sensing Facility (PSF) at Purdue University. The objective of this paper is not to provide an exhaustive review of current LOC systems, but to describe research developments made for the purpose of conducting physiological measurements in microgravity with examples of patents that support space missions. Keywords: electrochemical sensor, ion-selective electrode lifetime, all-solid-state ion-selective electrode, lab on a chip, Ceratopteris richardii.
Perception allows us to represent, interpret, and interact with our world, a process that depends on the human brain and on its ability to adapt to change. Confined space quarters exert harsh physical and mental rigors on humans, which can be detrimental to human brain function. However, technology can alleviate the effect of severe environmental conditions. When technology is compatible with our brain's mode of operation, the interface becomes intuitive, and human error is less likely. Technology systems and patents that support effective interaction between perception and our environment, along with their evolution, could lead to improved function and even comfort under strenuous conditions. Keywords: Perception, virtual reality, augmented reality, neural systems, circadian rhythms, human brain, cognition, environment, patent.
The immune system is one of the systems most affected in microgravity and during space flight. Substantial research and development activities are required in order to provide basic knowledge for appropriate risk management, including efficient countermeasures. The special sensitivity of immune system cells to altered gravity makes them an ideal model system to understand how gravity on Earth is required for normal mammalian cell function and signal transduction. As a direct result of reduced gravity, many studies have confirmed alterations in the molecular mechanisms and signal transduction processes in immune system cells - including the monocyte-macrophage system (MMS). The MMS belongs to the innate immune system and represents the body's first line of defense. The MMS is characterized by a fast, but unspecific immune reaction, and it activates the adaptive immune response. Given the extremely complex nature of cellular signal transduction networks, any observed effect in altered gravity could be secondary, adaptive, or driven by negative or positive feedback-loops, and thus far beyond the initial and primary cellular response. Therefore, coordinated in vitro studies with living human cells of the MMS in microgravity conditions, such as experiments on board parabolic flights, suborbital or orbital flights, and ground-based devices for simulated microgravity, provide suitable platforms to elucidate the underlying cellular and molecular mechanisms. They also help to clarify whether and to which extent gravity is involved in normal cell function or how cell function is impaired by altered gravity. We present technological developments for the investigation of the MMS in microgravity and space, in a coordinated research approach. Whereas the technology is often customized to the scientific project and just for singular applications, key components and key functions are usually patented. Keywords: Macrophages, innate immunity, microgravity, gravisensitivity, space flight.
This paper examines the application of humanistic intelligence design paradigms and wearable computing technologies to astronaut daily activities and future spacesuit designs. A specific focus is on display technologies providing an augmented and mediated reality. These wearable computer technologies (WCT) are discussed in the context of an astronaut's activities inside a spacecraft, during extra-vehicular activities, and on the surfaces of celestial bodies. Options for wearable computer displays with augmented reality interfaces are presented and recent patents in the field are included. Examples showing the astronaut's using an augmented and mediated reality display integrated into a headband during repair activities onboard the International Space Station, or a spacesuit visor during planetary surface exploration, are provided. The advantages of other WCT, such as sensors for brainwave and tactile feedback for assisting in awareness and spatial orientation, are also discussed. The scope of this paper is intended to attract interest from multiple disciplines pertaining to the nature of space projects in general. Furthermore, the application of the humanistic intelligence design principles provides a framework to assist current experts in improving WCT designs for astronauts in the future. Keywords: Humanistic intelligence, wearable computer, astronauts, spacesuit, vision systems.
Human deep-space missions to Mars and beyond will require development of a compact device that can provide comprehensive in-flight medical diagnostic capability to support the health of astronauts. Key features should include the ability to handle multiple sample types (blood, saliva, breath), and the ability to measure virtually any biomarker, including future biomarkers that may emerge. Here we identify compatible technologies and their associated patents that can be integrated to create such a device, to provide essential hematology information (blood cell counts, white cell differential) and to detect proteins and other biomolecules needed to assess spaceflight medical conditions. The ability to analyze breath and saliva specimens is a priority. These specimens are fully non-invasive hence no risk is associated with sampling and can provide rapid health assessment information that could be critical for urgent medical issues that may arise during EVA, prior to removal of the spacesuit. In addition to space applications, the device we envision would have applications for health care on Earth, in the military, in developing countries, and other settings with limited access to conventional medical resources.
A broad variety of countermeasures on the effects of weightlessness on human physiology have been developed and applied in the course of space exploration. Devices like treadmills, stretch ropes etc. have several disadvantages in common: they require a significant amount of crew time and they may not efficiently counteract the degradation of physiological structures and cellular functions. Some methods even include potentially painful or uncomfortable procedures for the astronauts. Thus, the application of Artificial Gravity (AG) generated by short radius centrifuges (they fit into space vessels) has been discussed and proposed by a number of scientists and space agencies as an alternative countermeasure during long-term space missions. Although there is a profound knowledge concerning, e.g., the cardiovascular system and immune responses acquired on long radius centrifuges, there is a remarkable lack of knowledge concerning the same issues on devices operating with short radius. In strict contrast to long radius centrifuges, there is a significant gravity gradient in the head-to-toe axis which comes along with the short radius and higher relative rotation velocity. Thus it is of utmost importance to continue investigating the effects of AG, especially by use of short radius centrifuges. The Short Arm Human Centrifuge (SAHC) at the German Aerospace Center (DLR) in Cologne, Germany, is the most advanced type of short radius centrifuges presently commercially available. Experience gained so far using the SAHC at DLR revealed that future projects on centrifuge devices with short radius should aim at a clear identification of the threshold level of the g-load, which is necessary to efficiently counteract the degradation of physical structures and an efficient support of cellular functions. A satisfying result would be combined countermeasure methods applied at a threshold concerning g-load and exposition time in the course of long-term sojourn in microgravity. Another future control or monitoring method to exactly dose AG training is heart rate variability, which offers an insight into neurovegetative and cardiovascular regulation. Centrifuges like the SAHC are also useful platforms to accommodate small biological experiments, e.g., experiments addressing the response of cultured cells to hypergravity. Here, we briefly review the issue of short radius centrifuges and also address our experience hitherto gained during a number of scientific projects carried out at the SAHC at DLR. Keywords: Centrifuge, hyper-g, cardiovascular system, neurovestibular system, countermeasure, artificial gravity.
