Evaluation of the Effect of the Difference between the Real Attachment Unit and the Sealing in the Study of the Stress-Strain State of the Solar Panel of a Small Spacecraft as a Result of a Temperature Shock

The author of this scientific paper studies the stress-strain state of the solar panel of a small spacecraft after a temperature shock. The temperature shock is caused by the entry or exit of a small spacecraft into or out the Earth's shadow. In this work is considered a one-dimensional model of thermal conductivity. It is assumed that the solar radiation flux falls properly on the solar panel. Violation of normality due to deformations is neglected. A special feature of this work is to take into account the actual fixing of the solar panel. The boundary conditions in the form of a seal are preserved. However, the mobility of the smallest spacecraft is taken into account as a result of the occurrence of a longitudinal force in the solar panel during a temperature shock. The results are compared with the simulation data without taking into account the mobility of the small spacecraft. The results of this work can be used in the design of small spacecraft for technological purposes to meet the requirements for microaccelerations.

Analysis of key technologies for creating multisatellite orbital constellations of small spacecraft

One of the key areas of modern world cosmonautics is the development of cluster space systems for various purposes, consisting of a large number of functioning spacecraft. This became possible due to a decrease in the mass of spacecraft due to the creation and use of new materials, the development of electronics and microelectromechanical systems, the use of the group launch method, the development of multi-agent technologies and inter-satellite communication sys-tems. There are projects of systems consisting of a large number of space objects, such as OneWeb, Planet, Starlink, Satellogic, etc. The main classes of devices used to create such multi-satellite systems are small satellites, including the number of micro (up to 100 kg) and nano (up to 10-15 kg) classes, which have significant advantages over heavy space-craft, especially in terms of the timing and cost of their creation. The deployment of multi-satellite constellations, in-cluding hundreds and thousands of satellites, requires fundamentally new approaches to the creation of spacecraft and the system as a whole at all stages of the life cycle. The article discusses the key technologies used to create multi-satellite orbital constellations based on small satellites at different stages of the life cycle - from the early stages of de-sign to the stage of operation and disposal (information from orbit). The experience of a joint project of Samara Univer-sity and the Progress Rocket and Space Center on the creation of a constellation of small spacecraft of the AIST series is presented.

Virtual space virtual satellite

“Virtual space virtual satellite” (VSVS) software solution has been developed for computing the geomagnetic field and studying the results of modelling small spacecraft flight at low orbit with different parameters. The application will allow to replace a number of experiments. In addition, SGP4 and IGRF models are studied due to their role in development of the solution, as are the possible applications in developing solutions for educating high school and university students as well as introducing them to space-themed projects.

Analysis of characteristics of electric propulsion systems intended for carrying out maneuvers of maintenance of low Earth working orbit of small satellites

An analysis of the mass of the working fluid and motor operating time of electric propulsion systems applied as a part of small spacecraft to carry out maneuvers of maintenance of the low Earth working orbit is carried out. The analysis is carried out for the small spacecraft with the weight in the range from 300 to 1000 kg functioning in working orbits with the height in the range from 400 to 600 km. When carrying out the analysis the values of the specific impulse of the propulsion system in the range from 800 to 1600 sec were accepted. Procedural guidelines for assessing the value of the required characteristic speed depending on the aerodynamic drag force, as well as for assessing the value of mass of the working fluid with account for the value of the specific impulse and defining the motor operating time of the propulsion system depending on the exhaust speed of the working fluid were used. The results of calculations given in the article show that the mass of the working fluid and the motor operating time vary depending on the height of the orbit and the mass of the small spacecraft and allow making quick preliminary assessment of the main design characteristics of the electric propulsion engines used to carry out maneuvers of maintenance of the low Earth working orbit of small spacecraft with different weight dimension characteristics during the prescribed term of active existence.

Investigation of the structural and functional reliability of the motion control and navigation system of a small spacecraft in the conditions of its multi-mode operation

In the course of the design, creation and application of complex multi-mode systems, which undoubtedly include the motion control system of small spacecraft for remote sensing of the Earth, when choosing the configuration of elements and connections between them, as well as the parameters of the system, it is advisable to explore the possibilities of using dynamic operation modes significantly affecting the structural and functional reliability of the system. Based on the new original concept of the parametric genome of the complex multi-mode object structure, introduced by the authors, the article describes the results of the studies of the influence of various options for activating the modes of operation on the structural and functional reliability of the motion control and navigation system of the small spacecraft “Aist-2D”. To assess the structural and functional reliability of the system under study integral indicators have been introduced. At the same time, the possibility of involving joint activation of the modes of operation, the equivalence of the intensities of utilizing the activation of the modes of operation and the homogeneity of the traffic control system were taken into account.

Past experience and future prospects for launching our country's small spacecraft from Plesetsk launch site

The paper provides an integrated analysis of the problem of the fast growing field of development and operation of Small Spacecraft (SS) constellations and participation of domestic launch site Plesetsk in solving this problem. It reviews the history of launches from Plesetsk, and describes the current status of work to build up and replenish SS-based orbital constellations. It describes major methods of SS launches. When describing multiple launches of SS on heavy launch vehicles it cites foreign practices of SpaceX Company, as well as lays down the prospects for development of our country’s heavy launch vehicles. As for the small-lift launch vehicles, it cites the experience of launching from Plesetsk of launch-vehicles Rokot and Soyuz-2 Phase 1v. For the super-small-lift launch vehicles, it cites the experience of USA and PRC, as well as our country’s development project of the launch vehicle Irkut, which is planned to be launched from Plesetsk, among other places. As for changes in the configuration of ground space infrastructure, the paper points out a trend towards processing SS at a single common processing facility (there is no need to construct processing facilities for each specific small spacecraft). The paper presents general trends in the system for operation of space facilities. The trends towards standardizing mechanical handling equipment in particular, and processing facilities in general, make it possible to lower development costs and speed up development schedules for advanced small spacecraft. Reducing small spacecraft processing time has a beneficial effect on the operational efficiency of the launch campaign, while the use of mobile checkout equipment makes it possible to quickly put together mobile and flexible processing facilities, the use of which will undoubtedly contribute to shaping the future of our country’s launch system. An important point made in the paper is the conclusion that in spite of our country’s lagging behind in super-small-lift launch vehicles, it has a significant scientific and engineering potential for developing this type of launch vehicles. Regardless of the value of other conclusions of the paper, the key point is that the current state of the ground space infrastructure facilities and the accumulated experience of specialists at Plesetsk make it possible to address the full spectrum of SS launch operations. Key words: small spacecraft, launch vehicles, ground space infrastructure, system for operation of space facilities.

NANOSATELLITE MOTION SIMULATION FOR TESTING THE SUN SENSOR

Nanosatellite (NS) began to perform complex missions that require high orientation. In this research, we developed a mathematical model of solar sensors to determine the orientation of a NS. Various moments of obtaining the angle of the sun's rays when they hit the solar sensors were presented. The test results of the solar sensors used to simulate various orbit scenarios are described in detail, and graphs of the solar sensor readings are plotted based on the results obtained. The article deals with modeling the motion of a NS in orbit. The NS is equipped with 6 solar panels. The VTS software was used to simulate the motion of the NS. Also, in the study of determining the orientation, two different problems were considered, that is, when the satellite is in the shadow part of the earth and when it is in the solar part of the earth. For these tasks, a mathematical model for determining the orientation was built. This method is very relevant for the study of small spacecraft.