ZHENG Si-hang，CHEN Yong-liang，LI-Chen，REN Jun-chen
（College of Quality and Safety Engineering，China Jiliang University，Hangzhou 310000，China）
Abstract： Aiming at the applicability and serviceability of traditional horizontal control systems which can not satisfy variousrequirements，to solve the problem that the leveling range，adjusting accuracy and response speed can not be considered at the same time，according to the principles of gyroscopic sensor and servo steering gear control，a new type of automatic horizontal control system wasdeveloped. With the three-axis gyroscope sensor detecting the direction of the acceleration of gravity to gain dip information，and digital
filtering and analysis by the STM32F103 microcontroller on the data collected，combined with PWM pulse width modulation technologyand PID algorithm to control the servo unit，the adjustment of two degrees of freedom was completed. And the mechanical structure of thesystem was optimally designed，effectively increasing the leveling range. The results indicate that the regulation accuracy of this automatichorizontal control system below 10'33"and the range of -90°~+90° can be achieved，and the horizontal error can be controlled within the
range of 0.1%~0.5%. In addition，the adjustment time is less than 2 s，and relative to other horizontal adjustment systems，it has lowerproduction costs and a higher degree of automation.
Key words：automatic leveling；three-axis gyroscope；servo steering gear；STM32