The article is devoted to the problems of development of the modern systems for control of the electric valve actuator of the rotary support device (RSD). It examines the tasks of modeling of real physical objects, including designing of the control systems, testing and development of the working prototypes. The most effective solution to the set tasks is the ModelBased Design - MBD. This method integrates into a single working process different stages of designing of the system, such as formulation of the technical requirements, modeling, development of the system, its debugging and testing. The most convenient instrument for realization of the model-oriented designing of the control system is MATLAB-Simulink environment. In this work on the example of two-coordinate RSD for the electric valve actuator of the azimuthal axis the first stages of MBD are considered in detail: - Development of the structural models based on a mathematical description and using the structural blocks of Simulink package and its Blocksets; - Development of the simulation models, using the masked blocks of SimScape package; - Development of the executable code by means of MATLAB-Simulink for comptrollers of STM32F103 series. Kits of program resources - MATLAB-Simulink, CubeMX, and Keil, the set of library modules - Target Support Package - STM32 Adapter, etc., offered to the developer, provide an opportunity for realization of the algorithm for operation of the systems of any complexity, which do not require engineers' deep knowledge in the area of programming. On the example of the developed system for control of the electric valve actuator of the azimuthal axis of RSD the algorithm for development of the executable code was presented, consisting of the following steps: - Initialization of the comptroller (indication of the peripheral modules involved in the control system with their tuning) in CubeMX program; - Programming of the algorithm for operation of the comptroller in MATLAB-Simulink environment with the use of different library modules, including the embedded and the pluggable ones; - Generation of the executable code with its subsequent recording in the microcontroller.