Mechanical Design And Experimental Research Of The Movement System Of The Automatic Blood Group Analyzer

With the increasing demand for blood group analysis,the number of blood samples to be tested in medical institutions is increasing,and the workload of medical staff is also increasing.Traditional manual and semi-automatic blood group analyzers have disadvantages such as long detection cycle,low accuracy,and low degree of automation.At present,most of the automatic blood group analyzers used in medical institutions rely on imports,and the matching blood group detection card are expensive.Most of the domestic automatic blood group analyzers are low-end products with low detection efficiency and accuracy.The economic,reliable and efficient automatic blood group analyzer has become one of the research and development problems that need to be solved in medical testing equipment in China.This subject is based on the key scientific and technological project of Changchun City “Development of an Automatic Blood Type Interpretation Workstation Based on Microfluidic Technology”.Based on the microfluidic blood group detection card independently developed by the project team,this paper focuses on the motion system of automatic blood group analyzer.The sample conveying mechanism,mechanical claw,centrifugal mechanism and the corresponding control system of the motion system are proposed reasonable design scheme.It has certain practical value for improving the localization level of such medical equipment.Firstly,the movement principle,working process and sampling needle adding method of the sample conveying mechanism are analyzed.The sample adding scheme is put forward and the driving mode of sample adding mechanism is determined.The threedimensional models of sampling needle and manipulator are established,and the reliability of manipulator structure is verified by static analysis.Combined with the movement process of the sample conveying mechanism,a reasonable transmission mechanism is selected,The modal analysis of the manipulator is carried out to verify that the manipulator has good stability and good positioning accuracy.The design requirements and working space size of the mechanical claw mechanism for grabbing the microfluidic blood group detection card are analyzed.The basic parameters of the mechanical claw are calculated,and two design schemes of the mechanical claw are proposed.The structure and material of the claw piece are determined,the three-dimensional model of the mechanical claw is established,and the overall structure design of the mechanical claw is completed.In the design of centrifugation mechanism,the principle and process of blood separation and the force of blood sample in microfluidic blood group detection card are analyzed.The model of rotary separation table is established and optimized.The load torque and moment of inertia of the rotary separator are calculated,and the corresponding drive motor is selected.Through the simulation analysis of the centrifugal mechanism,it is verified that the centrifugal mechanism has good stability at low speed or high speed.The control system takes C8051F380 as the core.Through the control of motors,sensors and other components,the coordinated control of multiple motors and the sequence of movements such as grabbing,centrifugation,oscillation of the blood group detection card,and sample transportation are completed.The test platform of automatic blood group analyzer is built.Using the control page,the operation of the prototype is realized.The test results show that each mechanism of the prototype can realize their own orderly movement and reach the predetermined position accurately,and the expected technical indicators are achieved.The validity and feasibility of the designed automatic blood group analyzer exercise system are verified.