Space Capsule Research Articles

Danish nonprofit tests space capsule

Danish nonprofit tests space capsule

Complex Mechatronic System Reliability Optimization Using Hybrid Genetic Algorithm

Reliability allocation optimization problem of a complex mechatronic system is a highly nonlinear constrained optimization problem, and hence solution to this kind of problem is of NP-hardness even with moderate scale. Due to the nonlinearity combined with multiple local extreme values, traditional optimization techniques fail to arrive at the global or nearly global optimal solution to the problem. Genetic algorithm incorporated with neighboring domain traversal searching technique is utilized in this paper to solve the complex mechatronic system reliability optimization allocation problem. Reliability allocation optimization of the life-support system in a space capsule, being a typical non serial-parallel system, is specifically demonstrated to show the satisfactory convergence performance as well as the important practical value of hybrid genetic algorithm. The simulation results show that the proposed method may gain better precision in solving the complex mechatronic system reliability optimization problem.

L'Allegro: Driving Home

Must I change my triumphant songs? said I to myself, Must I indeed learn to chant the cold dirges of the baffled, And sullen hymns of defeat? Walt Whitman, “Year That Trembled and Reel’d Beneath Me” Considering flesh, my body pushing back the carseat, speeding behind storm steaming and tailing away faster than I can drive. Setting sun behind me cracks open over southwest suburbs, November spilling light to flash sides of glassy Philly skyline: Molten silver holding building shapes, also greeny. I made one boy almost cry today. Made one almost cry! Billboard for the Pilots Union: Severe Turbulence Ahead: Lightning wraps a plane like a spiderweb a fly: Five years without a contract. Fly into that would you? Thinking about you. Twilight indigo and intensifying. Considering public artwork (1% of all building projects by law), a sideways spotlit space capsule by a cut-rate depression-era retro-futurist on top of the highwayside bank building that changed its name in the last most hostile takeover. Brushing aside the poison pill. A boy who said: “Tell me how I can ace this course.” Public art stinks always but a certain participation in the style of the day before yesterday cannot be denied. Windy: Big trucks swinging their trailers almost into my lane. I blow with them. Said I to myself, Have you given thought that what you want is options and considered nakedness and putting your heart away? Have you felt hurt? Given advice? What were you thinking, throwing things headward? Telling a boy: “Write.” Wishing I could. Nothing but months, weeks of jots, miscarriages. Gusts coming in over Tinicum Nature Preserve, Enterprise and Island Avenues. Airport: amber lights in the eastern sky: Jets spaced equidistant and reeling in as if hooked along an invisible fishline. The Walt Whitman’s Bridge’s shivery misty girders. Thinking: What’s it matter? Saying: “This won’t affect your final grade.” Nothing affects. Looking forward to you with your cronies and ethics violations I brush my teeth in the car. Nowhere to spit. Gusts across bare spaces between stadiums.

Features of electromagnetic thermal protection of space capsule

The problem of using a magnetic field to reduce heat fluxes on the surface of a flying vehicle is discussed as a continuation of the previous investigations [1–3]. A classical electromagnetic thermal protection scheme that uses a magnetic dipole oriented opposite to the oncoming flow is considered for a space capsule of Stardust (NASA space probe) mission entering the Earth’s atmosphere. It is shown that, for fairly high magnetic fields, the distribution of heat flux on the capsule surface weakly depends on the field amplitude, while the shock-wave stand-off distance from the surface increases in proportional to the field amplitude.

3D-MAGMA: A novel way of measuring gastrointestinal motility in patients with infectious diarrhoea

IntroductionThe current means of measuring gut motility are limited. Manometry and scintigraphic transit tests are the two most commonly used tests to investigate small bowel motility. Diarrhoeal symptoms are a...

MHD generator onboard space vehicle

The idea of extracting electric energy using a magnetohydrodynamic (MHD) generator arranged onboard space capsule is considered. For the conditions at one point on the trajectory of Stardust (NASA space probe) mission, it is numerically demonstrated that an electric power of about 3 MW can be gained by the proposed MHD generator, which amounts to abut 5% of the total enthalpy flux.

Assessing Astronaut Injury Potential from Suit Connectors Using a Human Body Finite Element Model

The new Orion space capsule requires additional consideration of possible injury during landing due to the dynamic nature of the impact. The purpose of this parametric study was to determine changes in the injury response of a human body finite element model with a suit connector (SC). The possibility of thoracic bony injury, thoracic soft tissue injury, and femur injury were assessed in 24 different model configurations. These simulations had two SC placements and two SC types, a 2.27-kg rectangular and a 3.17-kg circular SC. A baseline model was tested with the same acceleration pulses and no SC for comparison. Further simulations were conducted to determine the protective effect of SC location changes and adding small and large rigid chest plates. The possibilities of rib, chest soft tissue, and femur injury were evaluated using sternal deflection, chest deflection, viscous criterion, and strain values. The results indicated a higher likelihood of chest injury than femur injury. The mean first principal strain in the femur was 0.136 +/- 0.007%, which is well below the failure limit for cortical bone. The placement of chest plates had a protective effect and reduced the sternal deflection, chest deflection, and viscous criterion values. If possible, the SC should be placed on the thigh to minimize injury risk metrics. Chest plates appear to offer some protective value; therefore, a large rigid chest plate or similar countermeasure should be considered for chest SC placement.

Multiphysics Study of Structural Impact to Fluidic Media

The paper presents a fluid structure interaction based numerical study of impact loading for a hemispherical structure upon water and a space capsule water landing. The study has a strong relevance in the determination of the crashworthiness of aerospace structures upon water impact loading. Finite element based numerical techniques have been used for the analysis of the underlying transient dynamic and fluid-structure interaction. Smoothed Particle Hydrodynamics (SPH) and Arbitrary Lagrange-Eulerian (ALE) methods have been used to simulate the behaviour of the fluid (water) under impact conditions. The accelerations and velocities of the impacting objects have been validated with by experimental measurements and analytical results. Numerical analyses showed a strong potential for the use of developed computational fluid structure interaction models for analyses of water impact loading related problems.

SpaceX successfully launches Dragon space capsule

SpaceX successfully launches Dragon space capsule

NASA's Orion space capsule being readied for launch despite uncertain future

NASA's Orion space capsule being readied for launch despite uncertain future

Letter to Send in a Space Capsule

Letter to Send in a Space Capsule

Space capsule probed for asteroid dust

Hayabusa holds lessons for future sample-return missions.

Men for Mars

![Figure][1] Relaxation in isolation. CREDIT: SOURCE: IBMP If six men are crammed into a space capsule for 520 days, will they go crazy? Candidates are now competing to help answer that question. There's no crewed voyage to Mars in the offing, but the joint Russian-European Mars500 project is on track for a simulated year-and-a-half roundtrip to, and a 3-week field trip on, the Red Planet. Six men will enter a capsule this summer at the Russian Institute for Biomedical Problems (IBMP) in Moscow. Nine candidates are currently training in Russia. The final crew, to be announced in May, will comprise three Russians, two Europeans, and either a Chinese or another Russian. Astronauts who venture beyond the protection of Earth's magnetic field must dive behind protective shields periodically to avoid deadly blasts of radiation from solar flares. Otherwise, the daily routine is similar to life aboard a ship: 8 hours each of work, recreation, and sleep. Work includes medical tests, growing vegetables in the greenhouse, and mandatory exercise. Recreation includes the use of an onboard sauna. Unlike Russian cosmonauts, the crew won't be allowed cocktails. Six men have already successfully endured a 105-day version of the experiment last year. There was only one problem: European-style freeze-dried fare “did not match the Russian taste for food, which at the end led to some weight loss in some of the Russian crew members,” says project manager Jennifer Ngo-Anh. [1]: pending:yes

Testing the survival of microfossils in artificial martian sedimentary meteorites during entry into Earth’s atmosphere: The STONE 6 experiment

If life ever appeared on Mars, could we find traces of primitive life embedded in sedimentary meteorites? To answer this question, a 3.5-byr-old volcanic sediment containing microfossils was embedded in the heat shield of a space capsule in order to test survival of the rock and the microfossils during entry into the Earth’s atmosphere (the STONE 6 experiment). The silicified volcanic sediment from the Kitty’s Gap Chert (Pilbara, Australia) is considered to be an excellent analogue for Noachian-age volcanic sediments. The microfossils in the chert are also analogues for potential martian life. An additional goal was to investigate the survival of living microorganisms ( Chroococcidiopsis) protected by a 2-cm thick layer of rock in order to test whether living endolithic organisms could survive atmospheric entry when protected by a rocky coating. Mineralogical alteration of the sediment due to shock heating was manifested by the formation of a fusion crust, cracks in the chert due to prograde and retrograde changes of α quartz to β quartz, increase in the size of the fluid inclusions, and dewatering of the hydromuscovite-replaced volcanic protoliths. The carbonaceous microfossils embedded in the chert matrix survived in the rock away from the fusion crust but there was an increase in the maturity index of the kerogen towards the crust. We conclude that this kind of sediment can survive atmospheric entry and, if it contains microfossils, they could also survive. The living microorganisms were, however, completely carbonised by flame leakage to the back of the sample and therefore non-viable. However, using an analytical model to estimate the temperature reached within the sample thickness, we conclude that, even without flame leakage, the living organisms probably need to be protected by at least 5 cm of rock in order to be shielded from the intense heat of entry.

History of rocketry in India

The Indian Space programme took birth on November 21, 1963, with the launch of Nike-Apache, an American sounding rocket from the shores of Thumba near Thiruvananthapuram on the west coast of India. From a family of operational sounding rockets known as the Rohini Sounding Rockets, India's launch vehicles have now grown up through SLV-3 and Augmented Satellite Launch Vehicle (ASLV) to the current gigantic satellite launchers, PSLV and Geosynchronous Satellite Launch Vehicle (GSLV). Though we had failures in the initial launches of SLV-3, ASLV and PSLV, these failures gave Indian Space Research Organisation (ISRO) a thorough and in depth understanding of the nuances of launch vehicle technology that later led to successful missions. An entirely new dimension was added to the Indian space programme when a space capsule was recovered very precisely after it had orbited the Earth for 12 days. The future for launch vehicles in ISRO looks bright with the GSLV MKIII, which is currently under development and the pursuit of cutting edge technologies such as reusable launch vehicles and air-breathing propulsion.

Orion Crew Member Injury Predictions during Land and Water Landings

A review of astronaut whole body impact tolerance is discussed for land or water landings of the next generation manned space capsule named Orion. LS-DYNA simulations of Orion capsule landings are performed to produce a low, moderate, and high probability of injury. The paper evaluates finite-element (FE) seat and occupant simulations for assessing injury risk for the Orion crew and compares these simulations to whole body injury models commonly referred to as the Brinkley criteria. The FE seat and crash dummy models allow for varying the occupant restraint systems, cushion materials, side constraints, flailing of limbs, and detailed seat/occupant interactions to minimize landing injuries to the crew. The FE crash test dummies used in conjunction with the Brinkley criteria provides a useful set of tools for predicting potential crew injuries during vehicle landings.

Ballistic Impact and Crashworthiness Response of Aerospace Structures

In designing the next generation of aerospace structures, particularly those using advanced materials, understanding their response under crash and ballistic impact conditions is of critical importance. The applications where these types of behaviors are important are diverse and include fan containment systems for aircraft engines, impact resistant aircraft fuselage structures, crash dynamics of rotorcraft structures, impact resistance of the Space Shuttle thermal protection system, and landing systems for the new Orion manned space capsule. To explore the state-of-the-art technologies in this subject area, a symposium on the “Ballistic Impact and Crashworthiness Analysis of Aerospace Structures” was held as part of the ASCE 2008 Earth and Space Conference, from March 3–5, 2008, in Long Beach, California. In this special issue, papers based on the presentations given at the symposium are presented. Specifically, papers related to practical applications of impact-resistant structures in the area of space vehicles, rotorcraft structures, and aircraft engine fan containment systems are presented. Furthermore, there are also papers on material model development, special applications of nonlinear finite-element methods, and algorithms devoted to dynamic and impact analyses. In the paper “Multiterrain Earth Landing Systems Applicable for Manned Space Capsules,” Fasanella presents a survey of landbased landing systems used in past space missions and aircraft fixed wing and rotorcraft including parachutes, airbags, and retro-rockets, to examine potential applicability to the new Orion manned space capsule. The paper describes new finite-element simulations of water landings of the Apollo command module conducted using the LS-DYNA code, which can be used to establish a benchmark for studies of the new Orion capsule. LS-DYNA simulations of land impact of the Orion capsule are then presented. For these new simulations, a proposed airbag landing system is used, and the soil properties expected to be present during a land impact are characterized. In the paper “Orion Crew Member Injury Predictions during Land and Water Landings” by Lawrence et al., the LS-DYNA transient dynamic finite-element code is used to simulate the probability of crew injury during the landing of the Orion space capsule under various conditions. The relationship of the new results to previous studies using the Brinkley model and specially designed dummies is discussed. The applicability of this work to providing guidance for seat and helmet improvements for the Orion capsule designed to reduce injury to the astronauts is described. In the paper “Shuttle Debris Impact Analysis: Post return to Flight Real-Time Mission Support,” Firko et al. provide an overview of the assessment of debris impact on the Space Shuttle through the use of LS-DYNA finite-element simulations that took place during several recent missions. The general mission support role in the analysis of the severity of debris impact events is described. Specifically, analyses of the potential damage from insulation blankets coming loose and impacting different parts of the Shuttle during several recent missions is discussed. The finiteelement simulations served to quantify the risks to the vehicle from potential debris impacts. In the paper “Overview of the National Aeronautics and Space Administration Subsonic Rotary Wing Aeronautics Research Program in Rotorcraft Crashworthiness” by Jackson, Fuchs, and Kellas, an overview of the rotorcraft crashworthiness research being conducted at NASA Langley Research Center is presented. The development and testing of a new Kevlar composite deployable energy absorber designed to absorb crush loads is discussed. An overall description of the test program and finite-element simulations being performed with the goal of determining occupant injury during rotorcraft impact events into a variety of land and water surfaces is presented. A probabilistic analysis of the energy absorber concept is also described. In the paper “Ballistic Impact Response of Kevlar 49 and Zylon under Conditions Representing Jet Engine Fan Contain

Space capsule recovery—Evaluation of risk factors, safety plans and procedures and design of experiments for systems qualification

The Indian Space capsule (SRE-1) launched aboard PSLV-C7 rocket, was recovered successfully in the Bay of Bengal on January 22, 2007 after its orbital sojourn of 12 days. Apart from serving as a platform for micro-gravity experiments, SRE-1 demonstrated ISRO's capability in the field of orbital reentry and recovery technologies. Satish Dhawan Space Centre (SDSC SHAR), the Spaceport of India was given the prime responsibility of assessment of mission risk, formulation and execution of safety plans and procedures, design and conduct of trials for validating the mission-critical sub-systems as well as the physical recovery of the capsule. To achieve these objectives, a number of drop tests were designed and conducted by SDSC SHAR involving real time computer network, ground-based tracking and telemetry stations, communication systems, safety and material handling systems, target identification and recovery systems. Dissemination of relevant information and coordination with multiple external organizations such as Indian Coast Guard, Indian Air Force and Indian Navy is an important aspect of these experiments. This paper delineates the methodologies designed and implemented at SDSC SHAR for validating those critical systems whose functionality finally culminated in the success of the mission, enabling India to join the elite group of nations with reentry module recovery capability.

Interactive fuzzy multiobjective reliability optimization using NSGA-II

In many practical situations where reliability enhancement is involved, the decision making is complicated because of the presence of several mutually conflicting objectives. Presence of multiple objectives in a problem, in principle, gives rise to a set of optimal solutions (largely known as Pareto-optimal solutions), instead of a single optimal solution. This type of problem is known as multiobjective optimization problem (MOOP). In general, a MOOP can be solved using weighted sums or decision-making schemes. An alternative way is to look for the Pareto-optimal front. Many evolutionary algorithms (EAs) like genetic algorithm (GA) have been suggested to solve MOOP, hence termed as multiobjective evolutionary algorithms (MOEAs). Nondominated sorting genetic algorithm (NSGA-II) is one such MOEA which demonstrates the ability to identify a Pareto-optimal front efficiently. Thus, it provides the decision maker (DM) a complete picture of the optimal solution space. This paper presents the reliability optimization of a life-support system in a space capsule where reliability of the system is maximized while minimizing the cost. An interactive fuzzy satisficing method for deriving a Pareto-optimal solution preferred by the DM is presented here. Prior preference of the DM has been taken into account here. Using the concept of fuzzy sets and convex fuzzy decision making a multiobjective fuzzy optimization problem is formulated from the original crisp optimization problem. Different nonlinear membership functions based on the DM’s preference have been employed for the fuzzification. Then, NSGA-II is applied to solve the resulting fuzzified MOOP. Resulting Pareto-optimal solution gives the DM variety of alternatives to seek an appropriate solution by modifying parameters interactively according to his/her preference again. Various Pareto-optimal fronts under different preferences of DM have been reported.

Attitude control schemes for the first recovery mission of India

This paper describes the attitude control schemes for the various phases such as acquisition, on-orbit, orbit maneuver, de-boost maneuvers and coast phases of the India's first recovery mission Space Capsule Recovery Experiment-I (SRE-1). During the on-orbit phase, the SRE was configured to point the negative roll axis to Sun. The attitude referencing of SRE-1 was based on dry tuned gyros with updates from the attitude determined using on-board Sun sensors and magnetometer. For attitude acquisition, attitude maneuvers and for providing the velocity corrections for de-orbiting operations; a set of eight thrusters grouped in functionally redundant blocks were used. The control scheme with thrusters was based on proportional derivative controller with a modulator. In order to ensure micro-gravity environment during the on-orbit payload operations a linear quadratic regulator (LQR) based control scheme was designed to drive an orthogonal configuration of magnetic torquers which in turn produced three-axis control torque with the interaction of Earth's magnetic field. Proportional derivative control scheme with modulator was designed to track the steering commands during the velocity reduction as well as during the coasting phase of the de-orbiting operations. A novel thruster failure detection, isolation and reconfiguration scheme implemented on-board for the de-orbiting phase is also discussed in this paper.