Design And Research Of An Automatic Height Control System For Cutter Of Cotton Top-cutting Machine

At present, the cutting job is the only production link that hasn't realize mechanization in the process of cotton production. For the problems of missing or more cut,low efficiency,poor accuracy during cutting the top of cotton by machine in Xinjiang, According to development of Cotton Top-cutting Machine, Combined with the technical requirements of cotton and automatic control technology, designed an automatic control system of the cutter's height on the basis of the STC89C52 microcontroller core, GP2D12 Infrared sensor for the detection of components,based on 3MDZK-12 Cotton Top-cutting Machine.1. By analyzing the domestic and international Cotton Top-cutting Machine is proposed based on the development of infrared sensor-based automatic control system of the cutter's height. Analysis of the structure and the infrared sensor working principle of the whole system design, and system hardware components and functions of the overall design.2. To STC89C52 microcontroller as the core, the design of the infrared transmitting and receiving circuit, MCP3001A/D converter circuit, LCD1602 display circuit, MAX232 serial communication circuit, power supply circuit, buzzer alarm circuit, microcontroller clock circuit and reset circuit.3. Combined with the principle of automatic control of electro-hydraulic system, set up a mathematical model and determine the PID control algorithm; calibration the PID control system, the system simulation by useing MATLAB, optimization of system parameters; Based on uVision3 software development environment, developed the control system the main program, subroutine infrared range, display routines, serial communication subroutine, subroutines and alarm delay subroutine.4. Test the performance of GP2D12 infrared sensors, for the sensor output analog voltage of nonlinear problems, its output signal linearization; In order to reduce measurement error, its mean filtering. Through the experiment, the results show that the actual work to meet the requirements. Infrared range in the laboratory test rig built by orthogonal experimental design, arranging tests, using data analysis software MINITAB and DPS results on the measurement range and variance analysis, the impact of measurement error in the primary and secondary factors to find more excellent combination. From the experimental results can be seen, the infrared distance measuring system can meet the requirements of precision. Through analysising the measurement data, find the cause of the error, it provides a strong theoretical support for the further study of the automatic control system.