Recognition of radiation from celestial bodies by technical means is an important task in the orientation of spacecraft. For a device that is part of the Earth orientation device, a variant of modeling an electronic signal amplifier received from a pyroelectric sensor is studied. On the recommendation of the developers, the properties of trans-impedance operational amplifiers were studied, and suitable coefficients for the negative feedback circuit were selected. The type of output signal of the model is studied in comparison with the recording of values taken from a real photodetector. The preferred design of the model in the Matlab Simulink environment is shown – a model defined by an electrical circuit using the Simscape Electrical library.

Keywords: simulation of electric circuits, space orientation, photodetecting device, transimpedance amplifier, optoelectronic devices, space instrumentation

The article reveals the results of the work carried out on modeling the dynamic model of the electric drive of the scanning mechanism of the Earth orientation device, which is based on a hybrid stepping motor. The simulation is based on NEMA 17HS3410 motor parameters. A brief description and features of hybrid stepper motors are provided. The simplest model of an electric drive is considered, in which there is a rigidly set moment of force, a moment of inertia of the rotor of an electric motor, and also the moments of dry friction and the moment of liquid friction are taken into account. It is shown how the change in the value of fluid friction affects the general behavior of the mathematical model of a hybrid electric motor. The behavior of a single-pole stepper drive is simulated. The relationship of the value of the moment of force acting on the rotor with the passport characteristics of the investigated electric motor is considered. The possibility of controlling the scanning mechanism based on P- and PI-controllers is estimated.

Keywords: electrodive, Simulink, moment of force, inetria moment, liquid fricton