Design And Research Of Control System Of Sample Grab Manipulator For Pathological Section Dyeing Machine

The automation is the development direction of medical diagnosis and treatment technology.As a necessary measure for diagnosis of cancer,the degree of automation is low now.The thesis focuses on studying a high-precision,high-efficiency and low-cost manipulator system used in pathological section dyeing machine.On the basis of analyzing the development demand of pathological section dyeing machine,this thesis studies the structure and control mode of system.According to the operation characteristics,the control frame which contains hardware part and software part is designed.Firstly,the hardware design circuit includes modules of power supply,CAN communication,limit switch and stepper motor drive.The main work contains selection of components,design of schematic and drawing of PCB circuit boards.In view of the stable operation,it designs the control software which includes CAN communication program design,timer,external interrupt and control algorithm.During the design of algorithm,it introduces the fuzzy adaptive PID control algorithm into the motor speed control after analyzing the running speed curve and characteristics of it.In this algorithm,it designs reasonable element values corresponding to membership function for controlling the sampling frequency of this algorithm,thus achieving the speed curve showing as S curve,and reducing the frequency of out of step.Then,it verifies the feasibility of algorithm by using Matlab software.On this basis,it imports the designed control algorithm into STM32 chips by Keil uvision5 software.The result further verifies the control effect of algorithm.In addition,based on the improvement mentioned above,the thesis builds the nonlinear out-of-step mathematical model of stepper motor.For further improving control accuracy,and achieving the precise control of manipulator,thesis uses the least square curve fitting method to estimate out-of-step of motor and compensate these in advance.Finally,the open-loop thesis builds test system to verify the feasibility of manipulator control system.The results show that the system has good operation stability,fast response speed,high control accuracy and generalization of algorithmic programs,etc.In conclusion,it can basically meet the overall needs of pathological section dyeing machine research.