Research On The Geometric Parameters Detection System For Swing Arm Type Metro Contact Rail

Urban Rail Transit Since the opening of the first subway line,the contact rail traction power supply method has been applied,and has been increasingly valued with the development of modern new materials,new structures and new thinking,especially with the subway in the suburbs.Extend,the contact rail power supply is more suitable for the transition between the subway tunnel and the overhead line than the catenary power supply,making it the preferred traction power supply mode for many new subway lines.The correctness of the contact rail stagger and conductor height geometric parameters directly determine whether the subway power supply system can work normally.If the geometrical parameters of the contact rails deviate from the normal values,it will affect the flow received by the locomotive and even affect the traffic safety.Therefore,it is of great significance to detect and detect the abnormal changes in the geometric parameters of the contact rails to ensure the safety of the subway.At present,the geometry of contact rails in China mainly relies on a large number of measuring workers to conduct sampling inspections using contact rail inspection scales.Workers have high labor intensity,fewer detection points are prone to missed diseases,low measurement accuracy,and low measurement efficiency.Some subway operation departments at home and abroad are trying to add non-contact photoelectric measuring beams to subway trains or installing sensors on receiving shoes to achieve intelligent and rapid detection of the subway’s contact rails,but their cost is high.Complexity,measurement accuracy is not high.The track inspection instrument is a digitized and intelligent precision measurement instrument which is equipped with a large number of railroad public works systems for detecting the geometric parameters of the track,and the subway system is also widely used.This paper designs a contact rail geometric parameter measuring system based on the extended function module of the track checker,which can be mounted on a track inspection trolley to form a measurement function combination of track geometry parameters and synchronous measurement of contact rail geometry parameters.The structure of the contact rail measurement system(using the rail car body,as well as the gauge and level measurement section),can also significantly save labor costs(one job completes the orbit,contact rail two-item detection task),and has high detection efficiency and measurement accuracy High,high measuring point density,low cost,has a broad market application prospects.In this paper,the overall design of the contact track measurement system is completed.A swing arm contact rail measurement system scheme is proposed,a measurement mathematical model of the measurement mechanism is established,a mechanical positive solution of the contact rail geometry parameter measurement is obtained,and a mechanical structure is implemented.The detailed design of the circuit structure,the upper and lower position machine software,etc.,manufactured the prototype,and realized measurement functions such as data acquisition,processing,analysis,waveform operation,over-limit alarm,and disease report.At the same time,two different calibration methods for direct calibration and mechanical calibration of the swing arm contact rail measurement system are proposed.The sensor calibration algorithm,calibration method and its applicability in field emergency calibration,calibration and other occasions are studied.The mechanism calibration algorithm was studied,the mechanical inverse analysis of the contact rail geometry parameters was obtained,and the calibration bench of the contact rail measurement system was established.A complete calibration operation flow was formed and the calibration of the prototype was completed.In this paper,the measurement uncertainty analysis of the swing arm contact rail measurement system is also carried out,and the measurement of the contact rail geometry parameter of the prototype is performed with reference to the rail inspection instrument indoor metrology verification method.The test results show that the error of the indication value of each measurement point and each measurement of the prototype is within the range of the predetermined technical indicators.The repetitive accuracy of the stagger is 0.11 mm,and the repeatability of conductor height is 0.17 mm,which has reached the expected research target.At present,prototypes have been delivered to Guangzhou Metro users for official use.The research in this paper is for the lower-grinding contact rails.A slight modification can meet the requirements of the upper-abrasive contact rails.