Study On Control System Of Multi-frame Photoelectric Platform

A photoelectric scouting platform carried by an unmanned plane is a new kind of real-time image scouting equipment that is developing rapidly in last decade. It is a complicated system that composes of optics, mechanism and electronics. Based on theories and experiments, the following respects will be studied deeply for the multi-frame photoelectric scouting platform carried by an unmanned plane in this paper: coupling problem, effective method of filtering noise inside measurement signal of feedback elements, and practical control system design.First of all, in accordance with the construction characteristics of the multi-frame photoelectric platform, coupling equations of rotational inertia, kinematics and dynamics of each frame are presented. This research provides theoretical guidance for rational design of mechanics system, and also brings up requirement for control system design of multi-frame photoelectric platforms.Measuring signal accuracy of feedback elements has very effect on control function. At first, the characteristics of probability distribution and frequency spectrum of noise inside measuring signal of feedback elements are discussed. Statistic filter method is come up with for noise signal of being Gauss distribution. It is analyzed reason that statistic filter method is superior to arithmetic average filter method. Secondly, signal after filtered is discussed from several respects of time domain, frequency domain and phase lag. We can conclude practical range of each filter with respect to different applied condition. In a word, signal after filtered fulfills requirements of low speed stationarity and some compensation methods.Some problems that should be solved at full steam at designing velocity-stabilized loop are discussed. According to these, square lag and lead correction and nonlinear acceleration compensation are put forward. Gain of open loop is upgraded greatly. At the same time, overshoot is restrained effectively. System control effect is content terrifically. On top of this, tracking course is divided two phases of capture and stabilizing track. We apply control techniques of multi-mode and variable gain. Fast speed of capture and tracking precision of stabilization are improved greatly.In the end, the theories and technologies discussed in this paper are tested with experiments. The experiment results are much more like the analyzed and simulated results. It verifies that the theoretical analysis in this paper is correct and it is very valuable for engineering.