The main purpose of dynamical processes modelling is to formulate the motion equations of the system with regard for active forces and constraints restricted its movement. Desirable properties of system's motion, which are provided by the influence of additional forces and by the variation of inertial system's properties, can be specified by the constraint equations. Nikolay Zhukovskiy studied two main problems on constructing motion equations: defining the force function, that determines a set of motion trajectories, and analysing its stability. The representation of constraint equations as partial integrals of motion equations allows to provide an asymptotic stability of the corresponding integral manifold and to solve the problem of constraint stabilization at numerical solution of dynamics equations. © Published under licence by IOP Publishing Ltd.