Research On The Key Technology Of Side Swept Draft Detection System Based On Sliding Rail

The establishment of Xiangjiaba Hydropower Station makes the reservoir area a safe deep-water navigation area for ships.The navigation condition in the reservoir has been improved significantly along with the shipping industry vigorous development in Jinsha River.The maritime sector and the navigation management have invested a lot of human power and material resources to test the draft of ship.They have achieved some success,but the technology is still immature.In this paper,the key technology of side swept draft detection system based on sliding rail will be studied in detail and the system is real-time,accuracy,and reliability.Firstly,the paper combines a floating type based on sliding rail with the side swept draft detection system because the workbench in the lower of Xiangjiaba Hydropower Station is far away from the testing sites.The idea combines compact dimensions,low weight,lower maintenance cost and high precision which can adapt to the harsh environment in the lower of Xiangjiaba Hydropower Station.Then,the paper architects tidy hardware system depending on strong parallel data processing capability of FPGA.The design can reduce transmission loss of analog signals by putting the data acquisition circuit at the bottom of the device.Finally,the system can calculate the ship draft combine with the equipment attitude of obliquity sensors and the equipment depth of pressure sensors.Also,the system introduces the acoustic ray trace to compensating actual measured data for sovling the problem of unusual sampling datain the metalimnion.The key technology of side swept draft detection system based on sliding rail contains two parts.The first part is desgining tidy hardware architecture to match the floating type based on sliding rail.The architecture need the equipment attitude of obliquity sensors and the equipment depth of pressure sensors for real-time attitude information.In addition,A long rail can increase transmission loss of analog signals so that the data acquisition circuit must be put at the bottom of the device to to deal with the received ultrasonic wave,such as magnification,shaping,conversion and acquisition.The other part is that the original data processing method of side swept draft detection system need to adapt to the change of the floating type based on sliding rail.The new type deserves a better solution of data processing and compensation because of construction error.In addition,the system should optimize the compensation of unusual sampling data in the metalimnion by introducing the acoustic ray trace.In the paper,the system has been tested in Dalian Maritime University Rescue and Salvage Laboratory and indoor swimming pool.And then,in Xiangjiaba downstream of ship lift approaches,has been put into operation.The system proves its science and practicality by the field trial operation and expert interrogatory.