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Development and twisting of space cable system relative to centre of gravity with help of gravity and internal forces |
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IPC classes for russian patent Development and twisting of space cable system relative to centre of gravity with help of gravity and internal forces (RU 2536611):
Method of orientation of space vehicle and device for its implementation / 2536010
Group of the inventions relates to control of angular motion of space vehicle (SV). The method includes additional generation of signals for assessment of orientation angle and angular velocity of rotation of space vehicle. Also the reference signals of the orientation angle, angular velocity and control assessment signal are generated. For the named orientation angle and angular velocity their differences with their assessed signals, and also the difference with their reference values are determined. The difference of control signal and its assessed value and, at last, the signal of correction of the signal of assignment of mathematical model and the signal of assessment of external noises using the respective formulas are determined. On this base the signals of assessment of orientation angle and angular velocity of space vehicle are determined, which are used for space vehicle control. The device in addition contains the reference model of the basic circuit of orientation of space vehicle and other necessary devices and connections.
Navigation satellite orientation system / 2535979
Invention relates to controlling orientation of an artificial earth satellite with solar panels. The disclosed method includes performing necessary turning of the artificial earth satellite along with solar panels and, separately, the solar panels about a first and a second axis. The antenna of the artificial earth satellite is directed towards the earth and the normal to the solar panels is directed towards the sun. Independent programmed turns about the first and second axes of the artificial earth satellite are performed in intervals of uncertainty of orientation of the artificial earth satellite on shadow orbits. In different versions of said turns, after the first turn, the artificial earth satellite is held in an intermediate position and normal orientation of the artificial earth satellite is then restored. This improves the accuracy of predicting movement of the artificial earth satellite on shadow orbits and accuracy of measuring the range to the artificial earth satellite.
Control over orbital spacecraft / 2535963
Invention relates to in-flight control over spacecraft equipped with heat radiator and solar battery. Proposed process comprises spacecraft flight in orbit around the planet with solar battery turn to position corresponding to normal to solar battery working surface directed to the Sun. Spacecraft orbital orientation is constructed whereat solar battery spinning plate is parallel with spacecraft orbit plane while solar battery is located on the Sun side relative to orbit plane. Spacecraft orbit altitude and angle between direction to the Sun and spacecraft orbit plane are defined. Magnitude of said angle (β*) is defined whereat duration of turn shadow section equals the necessary time of radiator heat release in said turn. Orbit turns are defined wherein current magnitude of said angle is larger than β*. In said turns, solar battery is turned around crosswise and lengthwise rotation axes unless shadowing of solar battery radiator. Note here that minimum departure of orientation of solar battery working surface to the Sun. Spacecraft orbital flight is conducted in near-circle orbit at altitude not exceeding a definite design value.
Method of holding spacecraft in geosynchronous 24-hour orbit / 2535353
Invention relates to control over spacecraft, particularly, to holding of geosynchronous spacecraft in preset are of stay and collocation with the other geostationary spacecraft. Proposed method comprises determination and correction of initial inclinations and longitude of injection orbit ascending node with allowance for epoch of spacecraft placing in orbit and term of its active existence. Note here that the time of beginning of operation in geostationary orbit when spacecraft orbit inclination reaches maximum permissible value iper. area. The latter corresponds to permissible reach in latitude at the boundary of nominal spacecraft stay area in altitude. Stable and minimum eccentricity magnitudes are defined. Eccentricity vector is corrected so that it equals the nominal value for spacecraft collocation and spacecraft orbit apse line is aligned with that of nodes. Spacecraft active collocation is executed at changing the inclination from 0 to iper without interaction with adjacent spacecraft control centres. At inclination larger than iper , eccentricity is increased to minimum with setting of Laplace vector in direction from the Sun. Note here that eccentricity vector is not corrected unless the end of spacecraft active existence term termination. At inclinations larger than iper, eccentricity vector equals modulo and is spaced apart relative to eccentricity vectors of the other spacecraft.
Space vehicle correction engine test method / 2535352
Invention relates to control of movement of space vehicle (SV). According to the proposed method, thrusts of correction engines (CE) (control accelerations) are determined as per total changes in a period of SV revolution from correction to correction. The latter are performed with one and the same CE and a thrust level of those CE is estimated. For reliable understanding of thrusts of a pair of mutually opposite located CE, series control activations of the same pair are performed from time to time with equal pulses. Discrepancy as to total pulse of thrust is entered in equal parts with an opposite sign to the implemented pulses. As a result, reliable thrust levels of CE in operation are obtained.
Method for generation of control actions on spacecraft / 2533873
Invention relates to spacecraft (SC) motion control using solar radiation pressure forces distributed over SC working zones. The latter are formed as flat parallel optically transparent droplet flows. Distance between droplets of R radius in each flow in its lengthwise direction (Sx) and frontal-lateral direction (Sy) is divisible by . Number of flows is . By mutual bias of flows in direction of their motion for distance droplet mist flows are generated in number of . Each of the mentioned flows is biased relative to previous flow for distance in frontal-lateral direction. Thus opacity in frontal-lateral direction and transparency in direction of plane perpendicular to a flow is created. Unit distributed light pressure force is regulated by changing radius and number of droplets coming to point of it application in unit time. Total action value is regulated by changing number of droplet jets.
Method of clearing space debri from orbit / 2531679
Invention can be used to move space debris from working orbits to recycling orbits. The method includes taking towing spacecraft and a self-contained docking module into the region of an orbit from which space debris is to be cleared. The sequence of removing space debris is selected by comparing a criterion, for example the probability of the space debris colliding with other space objects, for each space debris. Compensation for accumulated errors of motion parameters of the towing spacecraft during previous manoeuvres, as well as the pointing system is distributed between correcting pulses of the towing spacecraft at the long-range guidance step and of the self-contained docking module at the self-guidance portion.
Antifailure protection of rocket multiplex control system / 2521117
Proposed method comprises generation of data signal in every channel corresponding to a definite combustion chamber as the difference between command signal and feedback signal, generation of control system channel cut-off signal as the signal of setting actuator rod on said channel to mid position. Channel cut-off signal is generated in case the data signal modulus integral calculated at preset-duration time interval exceeds the preset threshold. Note here that command signals of other channels are generated as sums of or difference in pitch, yaw and bank control signals and cut-off channel feedback signal with coefficients depending on cut-off channel number so that required summed pitch, yaw and bank control moments are actuated.
Method to control spacecraft placing into orbit of planet artificial satellite / 2520629
Invention relates to spacecraft (SC) motion control during placing it into orbit of planet artificial satellite using aeroassisted maneuver. In the phase of airbraking, following parameters are forecasted for the time of SC exiting planetary atmosphere: SC speed, angle to inclination to local horizon and altitude of transfer orbit apofocus. In this process in each of successive forecast points, SC motion is considered on remaining atmospheric flight segments for roll angles γ = 0 rad and γ = π. The mentioned above forecasted manoeuvring parameters are found for each of these angles. Their values are used during control of SC incidence change (close to its value corresponding to maximum quality) and issuing pulse of SC speed in transfer orbit apofocus.
Method of spaceship orienting and device to this end / 2519288
Proposed method comprises generation of signals for estimation of: spacecraft orientation angle, spacecraft sing angle and control. Signal difference of said parameters and their estimates are defined. Several formulas are used to calculate the correction signals of setting and estimation of external interference. Said corrections are allowed for at correction of orienting angle estimate signals and angular velocity signal. The latter are applied in spacecraft orientation control circuit. Proposed device comprises the following extra units: memory, adders, amplifiers, integrators interconnected and connected with other elements via system of switches. Proposed device incorporates models of the spacecraft orientation main circuit and flywheel engine.
Method of three-axis orientation of spacecraft in orbital coordinate system / 2247684
Proposed method is performed by information of orientation unit to Sun by introducing the orbit parameters into on-board computer followed by calculating the Sun position in observation field of orientation unit for each point of orbit for orientation of axes in orbital coordinate system; search angular velocity is set for spacecraft to ensure capture of Sun by observation field of orientation unit, after which angular velocity is decreased to zero ensuring position of Sun in observation field of orientation unit. Then spacecraft is turned in such way that Sun should move to required initial point; turning the spacecraft to preset points is continued for each orbital point.
Method of correction of parameters of longitudinal motion change program at terminal control of cryogenic stage guidance on preset orbit / 2254271
Parameters of motion of cryogenic stage at moment of cruise engine cutoff are predicted and radius of deviation of radius and radial velocity of cryogenic stage from their preset magnitudes are determined. Signals for correction of pitch angle and rate of pitch are shaped for compensation of said deviation. Pitch angle correction signal is limited at preset level and its excess above this level is determined. When signal is shaped for limitation, addition to correction pitch rate signal is formed. This correction is equal to product of said excess by ratio of functions of sensitivity of radial velocity of cryogenic stage to pitch angle and rate of pitch. Resultant pitch rate correction signal is formed as sum of this signal determined without taking into account pitch angle correction signal limitation and addition. Thus, priority follow-up of velocity error is ensured at limited pitch angle correction.
Method for location of space vehicles / 2275650
The method consists in the fact that in the intermediate orbit simultaneously with determination of the co-ordinates of the space vehicle (SV) at initial time moment t0 by signals of the Global Satellite Navigation Systems the determination and detection of radiations at least of three pulsars is carried out, and then in the process of further motion of the space vehicle determination of the increment of full phase ΔФp=Δϕp+2·π·Np of periodic radiation of each pulsar is effected, the measurement of the signal phase of pulsar Δϕp is determined relative to the phase of the high-stability frequency standard of the space vehicle, and the resolution of phase ambiguity Np is effected by count of sudden changes by 2·π of the measured phase during flight of the space vehicle - Δt=t-t0; according to the performed measurements determined are the distances covered by the space vehicle during time Δt in the direction to each pulsar and the position of the space vehicle in the Cartesian coordinate system for the case when the number of pulsars equals three is determined from expression where Dp - the distance that is covered by the space vehicle in the direction to the p-th pulsar; Δt - the value of the difference of the phases between the signal of the p-th pulsar and the frequency standard of the space vehicle, measured at moment Tp - quantity of full periods of variation of the signal phase of the p-th pulsar during time Δϕp; Np - column vector of the position of the space vehicle at moment Δt; - column vector of the space vehicle position at initial moment t0; -column vector of estimates of space vehicle motions in the direction cosines determining the angular position of three pulsars.
Method of forming program for orientation of cryogenic stage at terminal control of injection into preset orbit / 2282568
Swivel combustion chamber of cruise engine is used for angular orientation and stabilization of cryogenic stage of spacecraft. Proposed method includes predicting parameters of motion of cryogenic stage at moment of cut-off of cruise engine; deviation of radius and radial velocity from preset magnitudes are determined; angle of pitch and rate of pitch are corrected and program of orientation of thrust vector for subsequent interval of terminal control is determined. By projections of measured phantom accelerations, angle of actual orientation of cruise engine thrust vector and misalignment between actual and programmed thrust orientation angles are determined. This misalignment is subjected to non-linear filtration, non-linear conversion and integration. Program of orientation of cryogenic stage is determined as difference between programmed thrust orientation angle and signal received after integration. Proposed method provides for compensation for action of deviation of cruise engine thrust vector relative to longitudinal axis of cryogenic stage on motion trajectory.
Method of control of cluster of satellites in geostationary orbit (versions) / 2284950
Proposed method consists in measurement of parameters of satellite orbits, determination of orbital elements, comparison of them with required ones and performing of correcting maneuvers with the aid of thrusters. Satellite inclination vectors are brought to circular areas of their permissible change which are spaced apart so that angle between line connecting the end of vector with center of its circular area and direction to Sun should exceed right ascension of Sun by 180°. According to first version, vectors of satellite eccentricity are shifted to similar circular areas so that similar line lags behind direction to the Sun by half angular displacement of vector over circumference of its natural drift within circular area. Then, distances between satellites are changed within required limits compensating for quasi-secular increment of inclination vector and correcting eccentricity vector so that at passing the center of interval between point of circumference entry of its natural drift to its circular area and point of exit from this area, line connecting the center of this circumference and center of circular area coincide with direction to the Sun. In case circular area of permissible change of each eccentricity vector is close to circumference of its natural drift (second version), said line for this area is matched with direction to the Sun and no correction is made in this case.
Method for missile take-off from aircraft for orbit injection of payload / 2289084
The method consists in separation of the missile with a payload from the carrier aeroplane and its transition to the state with initial angular parameters of motion in the vertical plane. After separation the missile is turned with the aid of its cruise engine, preliminarily using the parachute system for missile stabilization. The parachute system makes it possible to reduce the duration of the launching leg and the losses in the motion parameters (and the energy) in this leg. To reduce the missile angular bank declination, the strand of the parachute system fastened in the area of the missile nose cone is rehooked. To reduce the time of missile turning towards the vertical before the launcher, the cruise engine controls are preliminarily deflected to the preset angles and rigidly fixed. By the beginning of missile control in the trajectory of injection this fixation is removed. In the other modification the missile turning is accomplished by an additional jet engine installation. It is started depending on the current angular parameters of missile motion so that by the beginning of controlled motion in the trajectory of injection the missile would have the preset initial angular parameters of motion.
Self-contained onboard control system of "gasad-2a" spacecraft / 2304549
Proposed system includes control computer, star sensor, Earth sensor, storage and timing device, processors for control of attitude, processing angular and orbital data, inertial flywheels and spacecraft orbit correction engine plant. Used as astro-orienters are reference and navigational stars from celestial pole zone. Direction of spacecraft to reference star and direction of central axis of Earth sensor to Earth center are matched with plane formed by central axes of sensors with the aid of onboard units. Shift of direction to reference star relative to central axis of Earth sensor is considered to be latitude change in orbital position of spacecraft. Turn of navigational star around reference star read off sensor base is considered to be inertial longitude change. Point of reading of longitude is point of spring equinox point whose hour angle is synchronized with the board time. This time is zeroed upon completion of Earth revolution. Stochastic measurements by means of static processing are smoothed-out and are converted into geographic latitude and longitude parameters. Smoothed inertial parameters are compared with parameters of preset turn of spacecraft orbit found in storage. Revealed deviations of orbit are eliminated by means of correction engine plant.
Method of control of spacecraft solar battery position and system for realization of this method / 2322372
Proposed method includes turning the solar battery panels to working position corresponding to matching of normal to illuminated surface of solar batteries with plane formed by axis of rotation of solar battery panels and direction to the Sun. Proposed method includes also determination of moments of the beginning of solar activity and arrival of high-energy particles onto the spacecraft surface. Then, density of fluxes of said particles is measured and the results are compared with threshold magnitudes. When threshold magnitudes are exceeded, solar battery panels are turned through angle between the said normal and direction to the Sun which corresponds to minimum area of action of particle fluxes on solar battery surfaces at simultaneous supply of spacecraft with electric power. When action of particles is discontinued, solar battery panels are returned to working position. Angle between direction to the Sun and axis of rotation of solar battery panels is measured additionally. In case threshold magnitudes are exceeded, solar battery panels are turned to magnitude of angle between normal to their illuminated surface and direction to the Sun which corresponds to minimum area of action of said particle fluxes on spacecraft surfaces (provided the spacecraft is supplied with electric power). System proposed for realization of this method includes units and their couplings for performing the above-mentioned operations. System is additionally provided with unit for measurement of angle between direction to the Sun and direction of axis of rotation of solar battery panels, as well as unit for determination of maximum current.
Method of control of spacecraft solar battery position and system for realization of this method / 2322373
Proposed method includes turning of solar batteries to the working position corresponding to matching of normal to their illuminated surface with plane formed by axis of rotation of solar battery panels and direction to the Sun. Proposed method includes also measurement of density of fluxes of solar electromagnetic radiation and high-energy particles determining the moments of beginning of solar activity and arrival of said particles to spacecraft surface. Additional measurement includes determination of appearance of signs of negative action of particle flux on spacecraft. During these moments, onboard solar batteries are charged to maximum level. When density of particle flux exceeds threshold magnitude, solar battery panels are turned through angle between said normal and direction to the Sun corresponding to minimum action of particle fluxes on solar battery surfaces. Discharge of storage batteries is hoped to close the energy gap on board the spacecraft. At minimum permissible level of storage battery charge, storage batteries are disconnected from load. When action of particles on spacecraft is discontinued, solar battery panels are returned to working position. System proposed for realization of this method includes units and their couplings for performing the above-mentioned operations. System is provided with unit for determination of current from solar batteries, unit for determination of moments of appearance of signs of negative action of high-energy particles on spacecraft and unit for setting the permissible level of charge of storage batteries.
Method of control of spacecraft solar battery position and system for realization of this method / 2322374
Proposed method includes turning the solar battery panels to working position corresponding to matching of normal to their illuminated surface formed by axis of rotation of solar battery panels and direction to the Sun. Proposed method includes also measurement of density of fluxes of solar electromagnetic radiation and high-energy particles followed by determination of moments of beginning of solar activity and arrival of high-energy particles to spacecraft surface. Method includes additionally measurement of spacecraft orbit altitude and angle between direction to the Sun and plane of spacecraft orbit. In case density of particle flux exceeds threshold magnitudes, solar battery panels are turned on illuminated surface of spacecraft orbit through angle (αs min) between said normal and direction to the Sun corresponding to minimum area of action of particle fluxes on spacecraft surfaces at supply of spacecraft with required amount of electric power. On shaded side of orbit, solar batteries are turned from direction of particle flux through maximum angle. When spacecraft escapes from shadow, reverse turn of solar battery panels is completed through said angle αs min. Upon completion of action of particle flux on spacecraft, solar battery panels are returned to working position. System proposed for realization of this method includes units and their couplings for performing the above-mentioned operations. System includes additionally unit for determination of intensity of spacecraft illumination, unit for measurement of spacecraft orbit altitude, unit for measurement of angle between direction to the Sun and spacecraft orbital plane, unit for control of turn of solar battery to position opposite to direction to the Sun, NO-gate and switch.
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FIELD: transport. SUBSTANCE: invention relates to space cable systems (SCS) and can be used for the transfer of SCS to a spinning mode in the orbit plane without the application of jet engines. SCS development is executed from its initial compact state in the circular orbit by the repulsion of objects at a low relative speed. SCS end weights are connected by a cable, its length being varied by a cable feed-haul-in device arranged on one of the end objects. The objects are separated by a vector of local peripheral speed, for example, by a pusher. The objects are driven by a start pulse to separate the objects in practically free paths at the free feed of the cable. The cable development is terminated by the SCS transfer to a stable mode of associated pendulum motion at the stretched preset-length cable. At a definite range of angular phases of this mode the SCS objects are stretched by hauling in the cable at a definite constant speed. This results in changing the SCS into the spinning mode at a preset power integral and fixed final end of the cable. EFFECT: relaxed weight-size constrictions of SCS, enhanced performances. 8 dwg
The invention relates to space technology, mainly to tethered space systems (KTS). The invention can be used to translate the CCC in the mode of its rotation about the center of mass (space "slingshot") in the plane of the orbit without the use of jet propulsion and, accordingly, without the cost of a working body on this maneuver. Under space tether system understand the totality of the two SPACECRAFT (SC) connected by a long thin rope. Potential areas of practical use of the CCC suggest three sustainable mode of motion CCC [1]: steady-state mode (mode gravitaional), the libration mode of oscillation and rotation mode. The General condition for the realization of sustainable modes of motion of the CCC is the motion of its center of mass in a circular orbit with a taut rope of fixed length. In rotation mode under the action of gravitational and centrifugal forces on the AC ligament occurs shallow artificial gravity. This effect can be used to create comfortable conditions for life and work of the astronauts, for cultivation in the space of plants, to refuel spacecraft fuel from a remote terminal, for conducting medical, biological, technological, and other experiments in low gravity, the level of which the reg is activated [1-3]. Rotating the CCC can also be used to generate a conductive wire of an alternating electric current, for monitoring of physical fields, to perform various orbital maneuvering space objects without the cost of fuel. Changing in a certain way the cable length of the CCC, it is possible to carry out the evolution of the parameters of its orbit, as well as mutual maneuvering limit objects ligaments. When the SC separation from the rapidly rotating ligament (space "slingshot") you can tell SPACECRAFT large enough extra speed to translate it to a higher or lower orbit, reentry or transfer to the trajectory of interplanetary flight. Using built in a certain way in space collectively, the "sling shot", you can establish a permanent transport channel in space [6-8]. Sustainable modes of motion CCC listed above are integral energy and quantitatively can be ranked dimensionless energy angular motion of a stretched ligament relative to its center of mass. By definition centuries Beletsky [1], the energy integral is dimensionless quantity whose value is determined by the initial conditions for the angular motion: , where φ is the phase of the angular position of the line of sight objects CCC; - the speed of angular movement of the CCC; - the angular velocity of the orbital motion of the center of mass CCC; rwith- geocentric radius of the circular orbit of the center of mass of the CCC (Fig.1); µ - constant gravitational field of the Earth. Mode gravitaional CCC the energy integral hg=-3. Mode librational oscillations with amplitude φo∈(0°, 66°) the value of the integral energy varies in the range hLieb=(-3; -0,5). Mode associated rotation value of the energy integral hBP>0. The translation of the CCC in the steady driving mode with the specified value of the integral energy on the cable of a given length is carried out, the initial state is, when two SPACECRAFT as a whole, make the movement of the original circular orbit so that the cable is compactly stacked on the feeder-sampling, located on one of the AC. In the technical aspect of the task of translating the CCC in the steady driving mode is not trivial, since it involves the simultaneous solution of two main tasks: 1) deployment of the cable to a predetermined length and 2) providing the required values of the parameters of the position and velocity at the end of the area of deployment of the CCC. The deployment of the cable to a predetermined length can be technically implemented in many different ways: - using a pulsed allowed - passive deployment; - using a pulsed allowed and further control the power cable tension - active deployment; using continuous thrust jet engines, installed on one or two AC cords - active deployment; using management integration of reactive forces and elastic forces of the tension of the rope. In the first two embodiments, the deployment is due to internal forces of the system. Required terminal conditions at the end of the plot cultivation can be implemented: - selection of the initial conditions of motion in repulsion and passive deployment CCC; - selection of initial conditions the motion and the parameters of force control cable tension during deployment CCC; by the power of the sample buffer and changes the moment of inertia angular motion; using jet engines. In the first three embodiments, the transfer of technology for sustainable mode of motion is due to internal forces of the system. Various combinations of management options to deploy the rope and options to achieve the desired terminal conditions define the various ways of transfer of technology for sustainable modes of motion. Consider the well-known and investigated methods of deploying and twist space tether systems. In [4, 6] is described and investigated using mathematical models method of deploying a cable and transfer the CCC mode librational oscillations [6] and the rotation mode [4] with a jet engine mounted on one of the AC ligaments. The process of twisting the CCC is performed in three stages: 1. First start up of the engine for cultivation of objects to a certain milestone and pre-twist of the CCC. 2. Passive breeding KA using centrifugal forces on a given length of cable. The relative velocity at the end of the plot cultivation is equal to zero. 3. The second burn of the engine at a fixed length of cable to achieve the specified parameters of the rotation. The conditions that minimize the consumption of the working fluid to perform the maneuver. In [5] is described and IP is ladawan way "gravitational spin two SPACECRAFT using two jet engines, installed on the SPACECRAFT. The process of twisting the CCC is performed in three stages: 1. Starting the engines for cultivation KA and unwinding of the cable to a length exceeding the desired value. At the end of the first stage of the CCC will be switched to the librational motion of the position of the maximum amplitude. 2. Passive libratory motion of the CCC to the output of the angular position of the line of sight its leaf objects in the neighborhood of the local vertical. 3. Rapid contraction of the CCC in the vicinity of the local vertical by the power of the sample of the cable to reduce the moment of inertia and translation of the CCC in the rotation mode. Investigated three laws sampling of the rope: a contraction with constant speed, the sampling of the rope at a constant power winch and contraction at a speed proportional to the distance between the SPACECRAFT. The described method is preferred according to the criterion of flow of the working fluid. The advantage of these methods is the possibility of implementing any energy modes rotation CCC arbitrary length. The disadvantages of these methods include: - the complexity of the design due to the presence of jet engines and reserves of the working fluid to them and, consequently, low reliability; - the finite and the finite energy resource; program motion control in both methods require the nalitch the e non-trivial control system. Devoid of these shortcomings, the group ways of twist, which is based on the sequential ejection spring plunger from the Board of massive orbital platforms leaf CCC [2]. The methods differ in the initial conditions of firing and conditions of supply cable when deploying the CCC. The ways have a common characteristic: 1. Before deploying SPACECRAFT docked at the orbital platform, which moves in an orbit, almost coincident with the desired orbit the center of mass of the CCC. The cable is compactly stacked on the device for depositing and filing, located on one of the AC ligaments. 2. The axis of the spring plungers are oriented in the plane of the original orbit. Department of the pulse due to internal forces of the system. The magnitude of the speed pulse separation unit meters per second. 3. The mass of the SPACECRAFT, forming a pair, are 1-10 kg, cable length is 100 meters, the angular velocity of the rotation system is 0.1-1.0-1the deployment time and the spin system is a few percent from the orbital period orbital platform. The advantage of these methods is the simplicity of technical and technological implementation twist the CCC in the plane of the orbit, as well as the possibility of multiple launch aboard an orbital platform rotating the CCC without flow of the working fluid to conduct the maneuver. the main drawback of these methods is significant mass-dimensional constraints imposed on the CCC. The proposed method of deployment and twist the CCC about the center of mass by gravity and internal forces accumulates merits considered analogues and practically free from the above disadvantages. The method has no restrictions either on the weight of the AC ligament, nor on the length of the connecting cable or consumption. The closest analogue among the considered methods of twist of the CCC is the way "gravitational spin two SPACECRAFT using two jet engines [5], which is considered as a prototype. The main difference of the proposed method of spin from the prototype is the use of the internal forces of the system at the first stage of the maneuver, which allows to exclude the use of jet engines. The deployment of the CCC in this case, the orbital plane of its center of mass is from the initial monolithic state system allowed by objects with small initial relative velocity. Leaf mass CCC mi, i=1, 2 are connected by a thin rope, the length of which may vary with the feeder-fetch the rope. Feeder-sampling can be installed on one of the AC ligaments. In the initial position before the separation system performs a monolithic movement in a circular orbit of radius r with. The separation of objects is made by the line vector of the local circular speed mechanical pusher. The potential energy of the pusher provides a starting pulse separation ΔV. Related rope objects are removed from each other for free trajectories under free supply cable. The process of deployment of the cable ends with a translation of the CCC in the phase state, from which it passes into a sustainable mode of the associated pendulum motion on the taut rope of fixed length. Graphically scheme of maneuver twist CCC presented on figure 2 in the form of the locus of the vectors of the limit of the masses [9]. To equal the limit of the masses ligament their trajectory of the relative motion is almost symmetric about the center of mass. Technologically maneuver twist the CCC can be divided into several stages: Stage 1. The point O in Fig.2, 3 - pulse transversal separation of the objects of the CCC on the original orbit Aboutwithand the transition SPACECRAFT into an elliptical orbit O1and O2. Stage 2. The trajectory 0-1 in Fig.2. Passive deployment of the CCC when the free supply of rope. Stage 3. The trajectory 12-2. Associated pendulum movement of the CCC on the taut rope of fixed length. Stage 4. The trajectory 2-3. The contraction of the CCC by the power of the sample of the rope at a constant speed. Stage 5. Plot tract the series 3-4. The CCC rotation with a given value of the integral energy for a fixed length of rope. The proposed method of deployment and twist the CCC with respect to its center of mass is studied on a mathematical model with the following assumptions: movement of the CCC is considered in the Newtonian field of attraction; - rope is lightweight, flexible and inextensible thread of high modulus material; - passive deployment CCC (section 0-1) supply cable from the device occurs without resistance; - contraction of the CCC is made with a constant sampling rate of rope. The research was conducted under the following problem statement. In the initial state of the CCC, consisting of two SPACECRAFT with a mass mii=1, 2, monolithic block moves in a circular orbit with the geocentric radius rwith. The connecting cable is laid on the feeder-sampling, which is installed on one of the AC. The device allows you to implement a free supply cable when removing the AC relative to each other after they are allowed, and to produce power sample of the rope at a constant speed winder, a=const. The repulsion KA is along the line of the orbital velocity vector using a spring plunger that implements the starting pulse speed separation ΔV. The maximum value of the velocity of the winder rope and pulse rate rastali the project for the AC are of the same order and do not exceed 10 m/s It is necessary to determine the magnitude of the pulse is allowed, the trajectory parameters passive deployment, pendulum motion and force fetch cable at speeds that allow to CCC from the initial state in the rotation mode with a given value of the energy integral hBP>0 for a given length of rope. The solution with the purpose of generalization of its results are presented in dimensionless parameters and variables: -- mass ratio leaf CCC; -- the dimensionless momentum allowed, where- the circular velocity of the center of mass CCC; -- the relative length of rope. stage 1. For definiteness, assume that when the repulsion SPACECRAFT with a mass m1got an accelerating pulse velocity ΔV1and KA Museum 2- brake pulse ΔV2. On the basis of additivity of momentum (quantity of motion) - "the momentum of the system is equal to the sum of the momenta of its individual particles, regardless of the possibility of neglecting the interaction between them" [10] taking into account the limitations on the capacity of the pusher ΔV1+ΔV2=ΔV, get the pulse rate allowed: Calculation of motion in elliptic orbits O1and O2(Fig.3), the geometric parameters of which depend on the pulse speed allowed: Relative and absolute limit movement of the masses along these trajectories are discussed in detail in the monograph [9]. It is established that these trajectories, there are two singular points, in which the speed of the relative movement of the leaf mass is zero and acceleration have opposite signs. These special points are the boundaries of the reverse relative motion of the SPACECRAFT. The angular position of the singular points does not depend on the mass ratio objects of the CCC and the magnitude of the impulse speed allowed range of values ΔV<30 m/C. These points are located on elliptical orbits (Fig.4) almost simme the ranks relative to the point Of separation of the CCC on the starting orbit. The angular position of the first singular point: ε11=42,50(true anomaly ϑ11=to 317.5°) and ε12=41° (ϑ12=139°). The arrival time of the end bodies in this point, expressed in units of the orbital period of the orbit of the center of mass, equal to=0,886. The distance between the end bodies. In the first special point begins the reverse motion mode of the CCC and the associated need a sample free of the rope. This process is completed in the second special point, and the parameters of relative motion of the CCC meet the conditions bumpless transfer CCC mode associated vibrational motion. In Fig.2 the second special point indicated by the symbols "l1and l2". The angular position of the second singular point: ε21=ϑ21=40,5° and ε22=41° (ϑ22=221°). Time of arrival at the point of. The distance between the end bodies. If we fix the length, the system will switch to the associated pendulum motion with the initial conditions: , and the value of the integral energy: This value of the energy integral is close to zero and corresponds to the transition state between librational and rotational movements of the CCC. stage 2. Associated pendulum movement of the CCC on the taut rope is described by equations [9]: where nwithlocal overload of the power cable tension. If we fix the cable length, the angular movement of the CCC on the interval φ∈(φ1that & Phi;2) can be described by the equation. The movement of the CCC at this stage is determined by the angular phase of initial and final States [9]: . Stage 3. The contraction of the CCC at a constant speed. The final state of the system after tightening to the specified level of energy of rotation hBPis uniquely determined by the phase angle φ3residual length of the rope l3and increment the dimensionless energy of rotation of Δh. According to [1], the parameters of the final status of the CCC are determined using the energy integral: . The challenge is to achieve the end state for a minimum time of pulling. Minimization of time of contraction at constant speed sampling of the cable is adequate to the task of maximizing the angular momentum of rotation of the CCC. The contraction of the CCC is made by the power of the sample cable. Management program retraction in the form of speed sampling of the cable a=const in the angular sector φ2<φ< & Phi;3specifies the increment of the energy of rotation in the guise Δh. Transition trajectory described by the system of equations: . Come to the optimal control problem with two movable ends: to determine the optimal program of tightening the CCC a(φ) for φ2<φ< & Phi;3and the corresponding transitional trajectory that brings the system from the initial state end at a minimum the length of the selected wire . The Hamiltonian of this system linearly dependent on the control. This means that the optimal control is a relay function: a=const≠0 for φ∈(φ2that & Phi;3); and=0 if φ∉(φ2that & Phi;3), and the optimal control problem thus becomes the task performance with edge detection angular sector (φ2that & Phi;3) is the sign function switch. Using the transversality conditions and necessary conditions for an extremum in the form: , you can solve the boundary problem for the equation . This integral can approximately be calculated under conditions allowing to apply theorem on the average: where;; ;. This equation establishes a relationship between the change in energy of rotary motion of Δh and resource costs maneuver in the form of a selected length of cable. As can be seen from these relations, resource costs depend on the initial φ2and the final phase of the sampling cable & Phi;3 =φ2+Δφ. This allows the original optimal control problem to minimize the problem of finding the extremum of parametric functions resource costs: , where the criterion function and examined in the extreme. A necessary condition for an extremum gives the equation , the solution of which determines the argument extremum: . When Δh→0 the summand B(Δφ)→1 and φ2≈π-0,5·Δφ, that is, the angular sector in the region tightening CCC symmetric with respect to the local vertical of the center of mass in the vicinity of the Zenith and Nadir. With increasing values of the parameter ∆ H symmetry is broken and the sector makes associated offset. The procedure for solving the problem of translation of the CCC in the rotation mode: - specify data source: rwith, ΔV, Δh, Δφ; - calculate the auxiliary parameters: ,; - determine the motion parameters of the CCC at the end of the deployment: φ1=91,5°,,; - define the boundaries of the field of coagulation CCC φ∈(φ2that & Phi;2+Δφ); - determine the average parameter valuesand A; - calculate the parameters characterizing the process of spin CCC: 1. The relative length of the selected wire. 2. The share of the selected wire after tightening CCC:. 3. The percentage of the selected cable Jh=J/ ∆ H. 4. The sampling time of the rope. 5. The relative velocity of the sample cable. 6. The end time of the maneuver: The time shall be taken from the moment of allowed objects on the starting orbit. An estimate of the time the maneuver is a half period of the reference orbit of the center of mass. In Fig.5-8 shows the graphical dependence of the main characteristics of the process of spin CCC. The dependence of the fraction of the selected cable from the increment of the energy of rotation of the CCC (Fig.5) is a clear and objective indicator of the quality of the process under investigation. This quality measure is not sensitive to the size of the sector tightening Δφ, and the value of this index is easy to calculate the radius of rotation of the CCC after its contraction. The percentage of the selected cable when tightening the CCC (Fig.6) is a universal indicator of the effectiveness of the process of spin, as quantitatively determines the resource costs in the form of a length selected Proc. of the sa unit increments the value of the integral energy of rotary motion. The bottom graph in Fig.6 built by the approximate formula: Jh=Å-1, Å=18+2,5·Δh, ·Δh≤3. Calculations show that the percentage of the selected cable per unit of energy of rotation when tightening the CCC does not exceed 6%. This is a very high indicator. In Fig.7 and 8 show plots of the velocity and time of sampling rope for two sizes of the sectors in the field of contraction of the CCC. In Fig.7 shows the graphical dependence of the required speed sampling of the cable in a predetermined angular sector Δφ to translate the CCC in the rotation mode with the energy indicator of Δh. The calculations are performed for the pulse separation ΔV=1 m/s Relative to the sampling time of the cable is proportional to the size of the sector and practically does not depend on the increment value of the integral energy of rotary motion. This is achieved by increasing the speed of the sample cable. This is a very important parameter from the point of view of practical implementation of the process of pulling. Obviously, the power sampling of the cable at high speeds is not the best conditions for operation Executive mechanical devices. Thus, the possibility of translation of the CCC mode associated rotation by separation and transversal allowed one monolithic object to starting a circular orbit, subsequent passive deployment of the cable to a predetermined length, the translation system is the mode associated pendulum motion with the subsequent contraction of the CCC by the power of the sample cable to switch the system mode associated rotation. All control inputs to the system are implemented at the expense of its internal forces. The proposed method assumes a rather simple technical feeder-fetch the rope and equally simple program to control this device. Estimated time to maneuver twist the CCC is a half period of the reference orbit of the center of mass. Maximum resource costs as the share of the selected cable per unit increment of the energy of rotation when tightening the CCC does not exceed 6%. References 1. Beletsky C. C., Levin, E. M., the Dynamics of tethered space systems. -M.: Nauka, 1990. - 336 S. (space flight Mechanics). 2. Dynamics of space systems with tether and swivel connections/ A. P. Alpatov, W. C. Beletsky, V. I. Dranovsky, A. E. Zakrzewski, A. C. Pirozhenko, H. Troger, B. C. Khoroshilov - Moscow-Izhevsk: center "Regular and chaotic dynamics", Institute of computer science, 2007. - 560 C. 3. Ivanov, C. A., Kupreev S. A., Liberzon M. R. Convergence in space with the use of cable systems.- M: Jaruzelski, 2010.- 360 C. 4. Mosquitoes Century. And. the Study of the dynamics of a single schema twist two spacecraft. Space research, T. XI, vol.1, 1973, S. 14-20. 5. Mosquitoes Century. And. About the gravitational spin of the two satellites. Space research, T. XII, vol.6,1974,, S. 856-862. 6. Sidorov I. M. Skin is the cable systems to carry out transport operations in space.- Report on the seminar in IKI, , Moscow, 1999 http://www.iki.rssi.ru/seminar/19991124.doc. 7. Sidorov I. M. About the use of cable systems for the creation of a permanent transport channel in space// Flight.- 2000-№8. - S. 36-39. 8. Cable systems for interplanetary flights / R. R. Nazirov, I. M. Sidorov, V. A. Frolov // Flight.- 2008. - N 2. - S. 21-26. 9. Shcherbakov Century. And. Orbital maneuvering space tether systems: monograph. - SPb.: WKA them. A. F. Mozhaiskii, 2010. - 185 S. 10. Landau L. D., Lifshitz E. M. Theoretical physics: textbook.- 10 T. T. I. Mechanics.- M.: Science, CH. nat. Ed.-Mat.lit., 1988.- S. 11. Cosmo, M. L., Lorenzini, E. C. Tethers in Space Handbook: - Smithsonian Astrophysical Observatory. -1997. The method of deployment and twist tethered space systems (KTS) relative to the center of mass, including undocking and pulse repulsion of the two connected by a cable of interest, the release cable on a given length, the output of the system in the mode associated pendulum motion with the subsequent selection of the wire transfer system in a rotational mode of motion, characterized in that the pulse separation is reported against the orbital velocity vector, when deploying the CCC is a free release rope and translation of the CCC in the rotation mode is mode associated pendulum motion in the angular range of phases φ∈(φ2that & Phi;2+Δφ),
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