Determination of Discrete-Structure Parameters of Coatings with Allowance for Residual Stresses

The authors suggest that the dimensions of a discrete section of a coating should be chosen on the basis of calculation of the critical crack spacing in cohesion cracking. This approach allows for residual stresses in the coating. The reliability of the calculation method has been verified experimentally by direct measurement of the crack spacing.     

Using adaptation methods to stabilize elastic oscillations of large variable-parameter satellites

Consideration was given to providing stability and some performance indices,—in particular, the transient time at reorientation—of the dynamics of large flexible-structure information satellites under a varying spectrum of its natural frequencies. A generalized system structure including the loop of adaptively adjusted additional feedback (AAF) was considered with the aim of providing the desirable system dynamics in the cases where the lower frequency approaches that of control of the “rigid” spacecraft motion. A procedure was presented to design an algorithm for adaptation of the coefficients of the AAF subsystem realizing the desirable dynamics of control of the large elastic satellites. The results of mathematical modeling corroborating efficiency of the proposed system were given.     

High-precision control of nonstationary aircrafts by roll angle

Control algorithms ensuring high-precision control of an object under coordinate and parametric disturbances and noises are designed. This problem is solved by introducing an additional adaptive control loop synthesized on the basis of adaptive system theory with reference models. Several ways of simplifying the proposed adaptive algorithm are considered.     

Operation algorithm of reference model-based adaptive system ensuring given dynamic precision of control of nonstationary dynamic object under uncertainty

A new adaptation algorithm was proposed for reference model-based systems operating independently of the intensity and spectral composition of the input actions. This fact enables one to make predictable the dynamic precision of the reference model-based adaptive system which, by the authors’ opinion, is the stumbling block to wide practicalization of the systems of the class under consideration.     

Methods of intelligent diagnosis for control of flexible moving craft

A new approach to the control of moving flexible mechanical systems based on the methods of intelligent diagnosis and forecast was proposed. While observing the requirements on stability and performance of control of the main (“rigid”) craft motion, this approach also stabilizes its elastic oscillations. A notion of the “model” function of the effect of basic control on the elastic oscillations in the presence of the dominating mode was introduced. The loop for adaptive adjustment of the basic algorithm of power-optimal control of the flexible craft motion was designed. For the proposed method of control of the elastic multifrequency moving craft such as the large space structure, some results of modeling were presented.     

Using the method of phase biplane to study dynamics of interactions of the elastic structural oscillations of the flexible spacecraft with the control system

A modal-physical representation of the mathematical model of flexible spacecraft enabling one to specify a diversity of the distinctions of the dynamics of controllable motion of the flexible objects was determined. The method of phase biplane enabling strict analysis of the dynamics of relay control of orientation of a flexible object with one dominating mode was described and extended to the method of the fuzzy phase biplane for approximate study of the dynamics of the multifrequency flexible spacecraft. Consideration was given to some important questions concerning the impact of structural flexibility on stability and performance of the control system of orientation of flexible spacecraft.     

Silicon structures with dielectric insulation obtained by vertical anisotropic etching

Silicon structures with vertical insulating walls were prepared for multielement devices with high element packing density requiring deep pockets in silicon single crystals. The technology is based on the anisotropic etching of (110)-oriented silicon crystals and filling the etch grooves with an organosilicon polymer based suspension.