Some psychophysiological and behavioral aspects of adaptation to simulated autonomous Mission to Mars

“Mars-105” experiment was executed in March–July 2009 in Moscow, at the Institute for Bio-Medical Problems (IBMP) with participation of European Space Agency (ESA) to simulate some specific conditions of future piloted Mars mission. In the last 35 days of isolation, in order to simulate autonomous flight conditions, some serious restrictions were established for the crew resupply and communication with Mission Control (MC). The objective of the study was to investigate psychophysiological and behavioral aspects (communication) of adaptation during this period of “high autonomy”. We used computerized analysis of the crew written daily reports to calculate the frequencies of utilization of certain semantic units, expressing different psychological functions. To estimate the level of psycho-physiological stress, we measured the concentration of urinal cortisol once in two weeks. To investigate psycho-emotional state, we used the questionnaire SAN, estimating Mood, Activity and Health once in two weeks.During the simulation of autonomous flight, we found out the different tendencies of communicative behavior. One group of subjects demonstrated the tendency to “activation and self-government” under “high autonomy” conditions. The other subjects continued to use communicative strategy that we called “closing the communication channel”. “Active” communication strategy was accompanied by increasing in subjective scores of mood and activity. The subjects, whose communication strategy was attributed as “closing”, demonstrated the considerably lower subjective scores of mood and activity. Period of high autonomy causes specific changes in communication strategies of the isolated crew.     

Electrodynamic stabilization of earth-orbiting satellites in equatorial orbits

A satellite with electrodynamic stabilization system is considered. Based on the method of Lyapunov functions, sufficient conditions of the asymptotic stability of direct equilibrium position of this satellite in the orbital coordinate system under perturbing action of a gravitational moment are obtained. These conditions allow one to ensure a rational choice of parametric control coefficients depending on parameters of the satellite and its orbit.     

Variations of ionospheric fluctuations of phase delay depending on solar activity: Data of the COSMIC experiment

We present the results of processing and analysis of more than 4500 events of radio occultation sounding of the Earth’s atmosphere observed in the course of the COSMIC experiment on the limb path ‘satellite-ionosphere-satellite’. Events observed in December 2011 (when a number of solar flares occurred) and in January 2012 (when a strong solar proton event took place) were analyzed. It is shown that small-scale variations of electron density increase in polar latitudes, equatorial region, and midlatitudes of the southern hemisphere in January 2012. In the same period, an increase of large-scale variations of electron density is observed during daylight hours in the equatorial region and in the southern hemisphere. No noticeable distinctions in comparison with days of quiet Sun were observed in December 2011.     

Earth–Moon libration point orbit stationkeeping: Theory,modeling, and operations

Collinear Earth–Moon libration points have emerged as locations with immediate applications. These libration point orbits are inherently unstable and must be maintained regularly which constrains operations and maneuver locations. Stationkeeping is challenging due to relatively short time scales for divergence, effects of large orbital eccentricity of the secondary body, and third-body perturbations. Using the Acceleration Reconnection and Turbulence and Electrodynamics of the Moon's Interaction with the Sun (ARTEMIS) mission orbit as a platform, the fundamental behavior of the trajectories is explored using Poincaré maps in the circular restricted three-body problem. Operational stationkeeping results obtained using the Optimal Continuation Strategy are presented and compared to orbit stability information generated from mode analysis based in dynamical systems theory.     

Space-borne technology and inversion techniques for radar

This presents recent progress of the state-of-the-art of space-borne radar technology in case of either earth-orbiting or planetary-orbiting satellites and space probes, respectively. In addition to that, recent progress is also discussed concerning specific inversion techniques to evaluate radar measurements; i.e., the art of deriving the relevant physical quantities to be determined such as terrain and depth profiles for planetary surface and/or subsurface structures ((3D)-profiles) from radar data measured depending on signal frequency, aspect angle, polarization, etc., as a function of time.     

Numerical prediction and wind tunnel experiment for a pitching unmanned combat air vehicle

The low-speed flowfield for a generic unmanned combat air vehicle (UCAV) is investigated both experimentally and numerically. A wind tunnel experiment was conducted with the Boeing 1301 UCAV at a variety of angles of attack up to 70 degrees, both statically and with various frequencies of pitch oscillation (0.5, 1.0, and 2.0 Hz). In addition, pitching was performed about three longitudinal locations on the configuration (the nose, 35% MAC, and the tail). Solutions to the unsteady, laminar, compressible Navier–Stokes equations were obtained on an unstructured mesh to match results from the static and dynamic experiments. The computational results are compared with experimental results for both static and pitching cases. Details about the flowfield, including vortex formation and interaction, are shown and discussed, including the non-linear aerodynamic characteristics of the vehicle.     

An Automatic Timing Receiver System Based on the Loran-C Navigational Network

This paper describes some new concepts in dealing with the circuitry for Loran-C automatic timing systems. The conventional analog techniques associated with phase-adjusting networks have been replaced by an incremental digital phase-shifting device. The Loran-C period generator includes facilities for delay compensation by means of an epoch monitor producing a 1-Hz output coincident with the master station TOC (time of coincidence). The required initial time information has to be accurate within ± 20 ms. The automatic format identification and decoding equipment together form a system which takes into account the information of every Loran-C pulse. Owing to the use of digital signal treatment, the synchronization accuracy is limited only by the resolution of the incremental phase shift. The automatic cycle selection device is based on sampling techniques where the derivative of the envelope is calculated. The time of coincidence has to be precalculated and fed into the thumbwheel memory of the epoch monitor, which is automatically initiated when the synchronizing operations are concluded. For VLBI purposes and transcontinental use, the accuracy of this system will be better than 1 ?s when post corrections, supplied by the U.S. Naval Observatory, are taken into account.     

Empirical modeling of the total electron content in the ionosphere

A method of modeling the total electron content (TEC) based on the semi-empirical ionospheric model developed in Irkutsk State University is suggested. Comparison with the Klobuchar model has shown that the proposed method provides a more accurate presentation of TEC. A conclusion is drawn that the use of this method for compensation of the ionospheric error in single-frequency navigation receivers would lead to a substantial increase in the accuracy of their positioning.     

PowerCore combining structure and batteries for increased energy toweight ratio

Much of the mass of a battery is comprised of nonreactive materials. In an NiH₂ battery, this includes the pressure vessel and 50% of the positive electrode. PowerCore reconfigures the battery materials to serve as a structural sandwich panel. The effective specific energy of the new device can exceed 100 Wh/kg. PowerCore is intended to handle power demands of low Earth orbiting communications satellites such as IRIDIUM. This paper describes the concept and development progress