Abstract:
As part of the synthesis of a tracking system for an unmanned aerial vehicle (UAV) under the influence of external uncontrolled disturbances and incomplete measurements of the state vector, the procedures have been developed for the synthesis of state observers and low-order disturbances of a new type, which do not require the building of dynamic models of external influences. The observation subsystem includes two state observers. The first observer gives estimates of velocities based on measurements of the UAV's center of mass coordinates. By using measurements of tracking errors, the second observer gives estimates of mixed variables (state functions, external influences and their derivatives), on which feedback is formed directly. It is noted that implementation of the algorithms developed, which do not require reconfiguration when external influences change, will increase the functionality of the UAV control system and its reliability in case of failure of measuring devices. The effectiveness of the proposed approach to the synthesis of the tracking system is confirmed by the results of numerical modeling. The results of modeling are presented (comparative analysis of closed systems with static feedback (assuming that all internal and external variables are measured) and with dynamic feedback using two approaches to solving the problem of evaluation under the influence of external disturbances: observers with large coefficients and with piecewise linear, limited corrective actions). It is shown that, despite the simpler setup, in systems with linear feedback it is advisable to use observers of the second type, and observers with large coefficients will be in demand in systems with obviously limited control.
Keywords:unmanned aerial vehicle, tracking, block approach, state and disturbances observer, high gains, piecewise linear functions.
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