VESTNIK of Samara University. Aerospace and Mechanical EngineeringVESTNIK of Samara University. Aerospace and Mechanical Engineering2542-04532541-7533Samara National Research University777410.18287/2541-7533-2020-19-1-96-105UnknownBringing spacecraft into solar-oriented attitude by the measurements of a single-axis angular-rate sensor and an optical solar sensorShipovM. G.<p><span lang="EN-US">Head of the Department of the Development of Spacecraft Motion Control Systems and Spacecraft Center-of-Mass Motion</span></p>maxim.shipov@gmail.comhttps://orcid.org/0000-0002-4265-3734SteklovaA. A.<p><span lang="EN-US">Chief of the Sector of the Development of Orientation Systems</span></p>steklova_aa@mail.ruhttps://orcid.org/0000-0002-6016-8417DavydovA. A.<p><span lang="EN-US">Leading Design Engineer of the Department of the Development of Spacecraft Motion Control Systems and Spacecraft Center-of-Mass Motion</span></p>arrrtttem@mail.ruhttps://orcid.org/0000-0001-9733-6165Joint Stock Company Space Rocket Centre Progress20052020191961052005202020052020Copyright © 2020, VESTNIK of Samara University. Aerospace and Mechanical Engineering2020<p>The algorithm of the turn of the spacecraft from an initial arbitrary angular position at an arbitrary angular rate to a solar-oriented attitude is investigated. Minimum essential equipment of the motion control system required for the purpose of ensuring maintenance of solar orientation is defined: a solar sensor, a single-axis angular-rate sensor, low-thrust liquid rocket engines. A solution of the problem of defining the spacecraft angular rate vector by the measurements of the deviation of the optical axis of the solar sensor from the sun vector and the single-axis angular-rate sensor is presented. The conditions under which control action on the rocket engines for the purpose of changing the value of the angular-rate vector for the Sun to get into the field of viewing of the solar sensor or for the spacecraft stabilization are defined. Mathematical modeling of the spacecraft attitude control system with the unknown initial state vector of motion is carried out. The results of mathematical modeling confirmed the efficiency of the proposed algorithm in terms of reducing propellant fuel consumption and high-speed performance. In comparison with the known methods of solving the problem of reducing angular speed (a lengthy process with the use of a magnetic system or a fast process with the use of a three-axis angular-rate sensor and rocket engines) the duration of the process of reducing angular speeds is the same as in normal operation, however, at the same time the problem of bringing spacecraft into the solar oriented attitude is solved.</p>Космический аппаратгашение угловой скоростисолнечная ориентацияуправление угловым движениемжидкостные ракетные двигатели малой тягисолнечный датчикодноосный измеритель угловой скоростиSpacecraftangular speed reductionsolar-oriented attitudeattitude controllow-thrust liquid rocket enginesolar sensorsingle-axis angular-rate sensor[1. Shipov M.G. Reduction of angular velocities of AIST-2D spacecraft using a system of kinetic moment dumping. Vestnik of Samara University. Aerospace and Mechanical Engineering. 2019. V. 18, no. 2. P. 121-127. (In Russ.). DOI: <a href='http://doi.org/10.18287/2541-7533-2019-18-2-121-127'>10.18287/2541-7533-2019-18-2-121-127</a>][2. Sevast'yanov N.N. Building of orientation modes on Yamal-200 communication satellite without angular speed sensors. Vestnik Tomskogo Gosudarstvennogo Universiteta. Matematika i Mekhanika. 2013. No. 3 (23). P. 104-110. (In Russ.)][3. Belenky A.D., Vasilyev V.N., Semyonov M.E. Solar pointing mode of the Meteor-M no. 2 satellite. Electromechanical Matters. VNIIEM Studies. 2015. V. 147, no. 4. P. 29-37. (In Russ.)]