Design Of Three Degrees Of Freedom Track Detection Platform And Research On Control System

With the rapid development of high-speed railway,the daily inspection requirements of railway track increase stringently.At present,domestic track daily inspection mainly depends on the staffs’ manual measurement using mechanical gauges.This traditional manual measurement methods not only cost huge manpower and material resources,slowly in detection speed,lowly in measurement accuracy,and can’t measure the track parameters in real time,it is difficult to meet the detection needs of high-speed railway,high-density traffic.Efficient and fast daily automated detection system is the important protection to improve the efficiency of railway operations and operational safety.It is urgent to develop an efficient,fast and accurate railway track daily inspection equipment for railway track detection.Chinese railway research institutions have developed a number of railway track detection systems,but all belong to large-scale track testing equipment.The cost of large-scale orbital testing equipment is very high in manufacturing and using,mainly used in rail line laying inspection and track quarterly large-scale detection,inconvenience to the use of railway construction and daily routine line detection,it is difficult to meet frequent daily testing needs.This paper focuses on the study of portable 3-DOF track detection platform.The series structure has the advantages of large working space,simple structure,low design complexity and simple motion control.In this paper,a 3-DOF tandem detection platform,including two degrees of freedom of movement and a degree of freedom of rotation,is designed to better meet the requirements of non-contact measuring instrument for space position detection and can meet the current complex daily detection requirements.In this paper,a portable track daily inspection platform is designed according to the characteristics of the 3-DOF series mechanism.According to the detection characteristics of the non-contact optical detector,the D-H spatial coordinate transformation method is used to analyze the spatial position of the platform structure,and the platform space structure rationality analysis is completed,combining with space agency.At the same time,the design of the 3-DOF platform’s servo control system is realized,and the mechanical balance analysis of the platform is completed by using the torque balance principle.The platform model is created by Creo2.0,and imported into ADAMS software to establish a virtual prototype model.The dynamic simulation,spatial location simulation have been achieved,and the structural mechanics balance and spatial structure rationality are verified.Finally,the servo control program is written by using MFC,and automatic control of 3-DOF structure is achieved.Based on structural design and analysis,the assembly drawings and parts drawings of the detection platform are drawn and the manufacture of physical prototype is completed.Field tests show that the platform physical prototype has good movement performance,which can meet the expected detection requirements and accomplish the detection task well.