To stabilize the phase position of the working body of the robotics complex a single-circuit precision electric drive system was developed based on the principle of phase-locked loop. The direct-driven electric drive is made on the basis of brushless direct current motor, which is switched to synchronous mode with minimal discrepancy between the phases of the reference signals and the pulse speed sensor. The phase error signal is fed to the input of the PID controller, which controls the pulse width modulation of the impulses controlling the operation of the power transistors of the autonomous voltage inverter. In a static mode, the control system of the autonomous voltage inverter implements a sinusoidal law of the pulse width modulation of the output pulses. The PID controller and the control system of the autonomous voltage inverter are programmatically implemented on the basis of the controller. In the process of analysing of the stabilization accuracy, the synchronous motor is represented by a second-order linear link, which establishes a relation between the phase deviations of the motor rotor and the stator magnetic field. The autonomous voltage inverter is represented by a zero-order hold whose coefficient of amplification on amplitude is found by the results of the approximation of its output voltage using the Walsh-Fourier series. The analysis of the phase stabilization process is performed on the basis of the state variables method taking into account the perturbations at the moment of load using the program which implements the recurrent procedure. The settings of the PID controller are determined by the variation results when the moment of load changes. Their initial values ​​are determined as a result of optimizing the system in terms of operation speed considering the condition of finite duration processes. It is assumed that there is no moment of load perturbation. The procedure for setting the PID controller parameters to the optimal operation speed mode can also be performed on the basis of neural networks. As a result of the calculations, it was found that with an increase of the load moment by 5%, the maximum deviation of the rotor phase was 0.22 us and 0.03 us of minimum deviation respectively.

The problem of flight tsafety , without regard to swift scientific and technical progress in industry of aviation equipment, become exceptionally sharp in our time. The statistical processing of empiric data is an actual task in monitoring of process of exploitation of propulsion MODULE of the Armed Forces of Ukraine and determination of tendencies of technical service and repair, directions of modernisation of armament and military equipment. The article considers the approach of the systems to the evaluation of reliability and safety of flights in relation to accomplishment of combat missions and preventionof aviation accidents. A methodological approach to the mathematical processing of statistical information for the period 2016-2019 on malfunctions was developed. The quantitative evaluation of their level is conducted on the generally accepted standardized indexes (statistical and probabilistic), specific methodology was here used. Index "parameter of failure flow" that characterizes the level of operating reliability and index "level of accident rate" that characterizes safety of flights were used in this methodology on ІСАО recommendation. Certain trends of changes of these indexes, the “upper control limit of reliability" and the considered conception of acceptable level of safety performance ( ALoSP) are expected for future periods for the different types of helicopters. On the base of operating data, the prognosis indexes expected, "upper control limit of reliability" on 2020 for the specific types of helicopters. As expected, according to obtained results, for all types of helicopters the mean value of this index will make not more than 4,3 failures per 100 flight hours. In accordance to conception of "acceptable level of "ALoSP" it is possible to distinguish three levels or "triggers" of flights safety : Acceptable level (Acceptable), special purpose level (Target), Critical level (Alert). These "triggers" are calculated taking into account the mean value of statistical sets of data about failures (for the last 3 years) and standard deviation that gives an opportunity to define the necessary additional measures of management to provide safety of flights. Authors came to the conclusion that conception of ALoSP is suitable for the evaluation of efficiency to provide flights safety of aviation of the Armed Forces of Ukraine with implementation of necessary adaptation to the existent terms of application of UKR aviation.

A conceptual approach to predicting of aircraft no-failure indicators during operational use is proposed. This approach is based on the use of methods of statistical analysis of operational data for a certain period of time. The results of predicting the failure flow parameter using a combined model of acceptable level and their standard deviation are presented. The results of predicting can be used to control the reliability (no-failure operation) of aircraft equipment in order to make grounded decisions about the continued operation of their equipment beyond the established life service. In order to create highly reliable aircraft it is necessary to predict failure rates, which involves the establishment of their range and quantitative values. To predict the thresholds of failure of the aircraft, it is advisable to use the following interval indicators of reliability: Ricao “accident level” indicator, which takes into account the number of flight failures detected in 100 hours and actually determines the dynamics of changes in the level of flight safety; “failure flow parameter, ω (t)”, which takes into account the total number of failures per hour of flight and determines the dynamics of changes in the level of operational The predicted value of the indicator of the “reliability upper control limit”, which determines the limit level of operatioanl reliability, at which further reliable operation of the aircraft is not desirable. According to the concept of “acceptable level of safety performance”, predictions of indicators for three levels of flight safety (acceptable, target, critical) are calculated, which need to be monitored in future periods of aircraft operation and make certain management decisions according to the proposed algorithm. The results of calculation for prediction indicators of reliability for specific types of aircraft according to their operation in the period 2017-2019 are presented.

On the basis of the developed technique for estimation of aviation equipment reliability indicators, the results of determination of orientating reliability indicators of helicopters and their functional systems are presented. The list and the main reasons for the change of reliability indicators for 2016–2020 are determined.

Step splitting control mode of the electric drives stepper motors working bodies of the positioning mechanisms of onboard aviation equipment is carried out by means of programmable controllers. From their output signals, pulse-wide signals are formed by means of drivers that control power transistors, which are included in the windings of a stepper motor. A simpler version of building control systems for stepper motors (SM) involves the use of programmable timers, which requires its reprogramming when changing the step splitting factor. In the process of step splitting the shape of the current in the winding of the SM approaches sinusoidal with an increase in the number of sine discretes stored in the controller's memory. However, in this case, the sine samples must follow at a higher frequency, which difficulties in programming them. There is a problem of finding new ways of programming in the controller's memory information about the changing shape of the supply voltage SM in the process of step splitting in order to ensure the maximum speed of the code and the minimum consumption of the processor time of the microcontroller. To solve this problem, it is proposed to specify information about the changing shape of the SM supply voltage not in the form of sine samples (table method), but the sum of the coefficients of the Walsh-Fourier series, the amplitudes of which depend of value of the step splitting factor. The Walsh-Fourier series is a natural basis for approximating the pulsed supply voltage of a stepper motor. Structural diagrams of digital and analog systems for stepper motors in the step splitting are proposed. In the digital control system, the Walsh matrix is entered into the permanent memory of the controller, the size of which is determined by the value of the minimum step splitting factor, and the column vectors of the coefficients of the amplitudes of the Walsh functions are entered into the random-access memory, each of which corresponds to its step splitting factor. The input controller sets the program for implementing the inverse Walsh transform to the control controller, as a result of which control signals for the driver are generated at the output of the DAC controller. As its output, control signals are generated for power transistors including in the windings of the stepper motor. In the analog control system, the main links are the Walsh functions generator and the block of summing coefficients. In the block of summing coefficients of each Walsh function is assigned an amplitude corresponding to a given step splitting factor, and then they are summed. As a result, a pulsed voltage is formed, which is fed to the input of the driver, as in a digital system. It is shown that an analog control system can be used to form low-frequency quasi- sine signals of high stability. They can be used in precision electric drives with high stability.