The problem of planning the observations of the given catalog of objects by a mobile observer, taking into account the imposition of restrictions on the moments of observation and the cost of moving the observer between the given boundary positions, is considered as a route selection problem. An algorithm for solving the problem as a problem of minimum dimension, equal to the sum of the number of observation objects and route segments (the number of observers), is proposed. At the same time, the control of the fulfillment of the remaining conditions and restrictions is carried out without increasing the dimension of the problem being solved by checking these restrictions at each step of the iterative process of solving the problem. Examples of constructing programs for observing terrestrial and astronomical objects from an aircraft/spacecraft (AC/SC) in solving a number of practical problems in the field of agriculture and space research are given, showing the effectiveness of using the proposed approach.

The uncontrolled rotational motion of the Progress M-24M and M-25M cargo spacecraft in the mode of one-axis solar orientation (the so-called “spin on the Sun”) has been reconstructed. The initial conditions of motion in this mode are the spinning of the spacecraft with an angular velocity of 2.2–2.4°/s around the normal to the sunward plane of the solar arrays. The duration of the mode is several orbits. The reconstruction was carried out using an integral statistical method based on telemetric values of the current taken from its solar arrays. As a result, the rotational motion of the spacecraft relative to the Earth–Sun direction is determined. A study of the spectrum of current oscillations during spinning was carried out, which explains the possibility of reconstruction based on such, at first sight, little informative data.

The uncontrolled rotational motion of Progress MS-07 and Progress MS-08 transport cargo spacecraft in the mode of gravitational orientation of a rotating satellite was reconstructed. Modes were implemented in April and August 2018. The reconstruction was conducted using an integral statistical method according to measurements of spacecraft angular velocity. Measurement data obtained at a certain time interval were processed together with the least squares method by integrating the equations of spacecraft motion relative to the center of mass. As a result of processing, the initial conditions of motion and parameters of the used mathematical model were estimated. The correctness of the reconstruction was checked by measuring the current taken from the solar panels. In the mode of gravitational orientation, the spacecraft rotated around its longitudinal axis with an angular velocity of 0.1–0.2 deg/s oscillating relative to the local vertical.

Russian Progress transport cargo vehicles (TCV) used in the International Space Station (ISS) project often keep residual resources of their basic systems upon they fulfill their main tasks in the ISS program. Utilization of these resources for space research if free flight of the TCV after its undocking from the station increases efficiency of both the TCV work and the ISS research program as a whole. Transport cargo vehicles can be used for investigations in various fields: in-flight tests, validation and certification of various equipment, materials, systems in the interests of other spacecraft; execution of experiments on the Earth or other objects remote sensing using additionally installed equipment; microgravity research aboard TCV taking into account its specific capabilities; launch of small satellites and sounds after TCV undocking from the station and transfer to the specified orbit, etc. New efficient technologies and flight control methods proposed to perform research on the base of the Progress transport cargo vehicles are considered in this paper.

We have reconstructed the uncontrolled rotational motion of the Progress M-29M transport cargo spacecraft in the single-axis solar orientation mode (the so-called sunward spin) and in the mode of the gravitational orientation of a rotating satellite. The modes were implemented on April 3–7, 2016 as a part of preparation for experiments with the DAKON convection sensor onboard the Progress spacecraft. The reconstruction was performed by integral statistical techniques using the measurements of the spacecraft’s angular velocity and electric current from its solar arrays. The measurement data obtained in a certain time interval have been jointly processed using the least-squares method by integrating the equations of the spacecraft’s motion relative to the center of mass. As a result of processing, the initial conditions of motion and parameters of the mathematical model have been estimated. The motion in the sunward spin mode is the rotation of the spacecraft with an angular velocity of 2.2 deg/s about the normal to the plane of solar arrays; the normal is oriented toward the Sun or forms a small angle with this direction. The duration of the mode is several orbit passes. The reconstruction has been performed over time intervals of up to 1 h. As a result, the actual rotational motion of the spacecraft relative to the Earth–Sun direction was obtained. In the gravitational orientation mode, the spacecraft was rotated about its longitudinal axis with an angular velocity of 0.1–0.2 deg/s; the longitudinal axis executed small oscillated relative to the local vertical. The reconstruction of motion relative to the orbital coordinate system was performed in time intervals of up to 7 h using only the angularvelocity measurements. The measurements of the electric current from solar arrays were used for verification.

At present, a number of scientific experiments onboard the International Space Station (ISS) are being run with the use of Steerable Pointing Platforms (SPP). The use of SPP is especially important because of the existing constraints on the ISS attitude maneuvers [1]. Owing to low level of momentum available from Control Moment Gyros on the US orbital segment, the ISS flies in quasiorbital attitude. Therefore, it is virtually impossible to point instruments that are rigidly attached to the ISS towards their survey targets by changing ISS attitude. This flight mode of the ISS calls for the use of SPPs onboard the station and development of control algorithms for turning the SPPs in order point them towards their survey targets. Since survey target catalogues list thousands of items, while resources available for implementing the possible pointing options are limited, there arises the problem of optimizing control during pointing of scientific equipment towards the survey targets. The paper describes a solution to this problem which uses a pointing system for video spectrometric equipment, which is being developed within the framework of an Earth studies experiment Uragan which is being carried out onboard the ISS Russian Segment (RS).

An approach to solving the problem of optimal scheduling of the sequence of spacecraft reorientations during observations of astronomical objects is discussed. The approach is based on problem formalization within the framework of graph theory and reduction of the problem to routing. Examples of constructing optimal observational programs for chosen stars are given. These examples show that the proposed approach offers the possibility of a significant reduction in energy expenditures for spacecraft reorientation. The applicability of the mentioned approach to optimizing traffic routes in various subnational entities is noted.

The technique and algorithms for optimization of planning the program of experiments carried out onboard an orbiting spacecraft are described taking into account the execution of service operations. A general approach to optimization of planning the experiments is used, developed for investigations onboard the Salyut and Mir space stations, and on the International Space Station (ISS). The approach is based on formalization of the problem in the form of an integer linear programming problem. In this approach, the spacecraft orbit is considered to be known, and the optimization of the planning of experiments is reduced to composing the optimum sequence of zones for the performance of experiments. The list of experiments, service operations, and tasks to be solved during the planning interval are assumed to be specified.

We estimate the accuracy of determining the weakly disturbed orbital motion of International Space Station by use of GPS-measurements as well as the, accuracy of forecasting such a motion. The measurements are the station coordinates in Greenwich coordinate system. They are received from on board equipment ASN-2401. The mean square errors of approximation of the measurements do not exceed 30 m when the motion is determined in a time interval less than a day. Processing the GPS-measurements in three-hour interval allows making the forecast of the motion on 15 hours forward with an error in the station radius vector not exceeding 400 m at a right choice of ballistic coeffitient. Systematic errorss in measurements of the station velocity, carried out by equipment ASN-2401, are revealed.