Design Of Portable Monitoring System For Vibration Acceleration Of Axle Box

With the development of high-speed railways in China,the operating speeds of many passenger dedicated lines such as the Beijing-Shanghai line and the Wuhan-Guangzhou line have reached 350km/h.Under high-speed driving,the safety of train operation has become increasingly important.As the key component connecting wheel set and bogie frame,the vibration acceleration of axle box is closely related to the operation safety of train.It can transfer the weight and load of the car body to the wheelset.In order to maintain the operation safety of the train,the maintenance personnel need to constantly monitor the wheel-rail relationship,and the wheel-rail relationship can be analyzed through the acceleration of the axle box vibration.However,in the project,there is a lack of temporary additional equipment specifically for monitoring the acceleration of the axle box vibration of the train.In order to reduce costs as much as possible and achieve rapid monitoring of the acceleration of the axle box vibration of the train,this article has designed a set of portable devices that can quickly monitor the acceleration of the axle box vibration.The monitoring system has important practical significance for studying the coupling relationship between wheels and rails,the polygon of the wheelsets,analyzing the irregularities of the tracks,and ensuring the safe operation of the train.First of all,this article introduces the research background of the subject and the development status of the axle box vibration acceleration monitoring equipment at home and abroad,and summarizes the data processing algorithm of the axle box vibration acceleration signal by scholars at home and abroad.Then,in view of the engineering requirements for rapidly monitoring the vibration acceleration of the axle box,the design requirements and functions that need to be improved of the axle box vibration acceleration monitoring system are clarified.Combined with the development trend of the embedded system,the overall design plan of the monitoring system,the design plan of the hardware,software and network monitoring center were formulated.Then,according to the proposed design scheme,this thesis completes the specific design of the monitoring system.In terms of hardware,the overall architecture of the hardware system was built,and the design of the hardware circuit diagram and PCB board was completed.In terms of embedded software,we have completed the transplantation of the RT-Thread realtime operating system,the development of hardware drivers,and the development of bootloader and application programs of the system.In the aspect of host computer software,the interface design of host computer was completed,and the data processing algorithm of host computer was studied.Finally,in order to verify the accuracy of the axle box acceleration measured by the monitoring system and the stability of the monitoring system,the calibration tests of acceleration were conducted at a metrology in Beijing.The calibration experiments show that:the acceleration error detected by the monitoring device is less than 5%,which has high precision.The on-site driving tests were carried out at a motor vehicle in Guangzhou.The driving experiments show that the monitoring system can monitor the vibration acceleration of axle box in real time,which is convenient for reading data and has good equipment stability.