Research of small spacecraft dynamiсs taking into account the influence of elastic vibrations of asjacent solar panels and aerodynamic moment

The article presents the analysis of the dynamics of small spacecraft (SS) with affixed solar panels which have a certain degree of elasticity due to their construction. A mathematical model of spacecraft disturbed motion during the boost phase is formed which takes into account the body elasticity and the presence of liquid filling. A finite-dimensional system of equations of SS elastic disturbed motion is formed in the process of constructing the model taking into account power dissipation. The issues of elastic vibrations that appear after the dynamic operations connected with SS re-orientation or reconstruction of some of its elements are discussed. Research has been conducted using a modeling complex to estimate the influence of elastic vibrations of the SS structure on the precision and dynamic characteristics of the control system such as the analysis of transition process duration and maximum amplitude of variations of the measured value of SS angular velocity. Dependences of SS angular speed on time have been obtained. The analysis of the results obtained shows that elastic vibrations of the SS structure have a strong impact on spacecraft dynamics in the spinning mode. It is noted that the vibrations in the pitch channel are the most crucial, It is there that vibrations  “out of the panel plane” and twist modes relative to  the symmetry axis of opened panel flaps take place  in the  nominal position of solar panels. Moreover, spacecraft motion during the process of its separation from the space rocket is discussed taking into account the influence of small aerodynamic moment.