Development Of VideoLog Underground Measurement And Control System

Videolog downhole TV is a logging tool that uses logging cable to obtain downhole highdefinition video in real time.In the current logging field,multi parameter logging tool has become a trend.Based on this,the demand of multi parameter extension of videolog downhole TV is proposed.The development goal of videolog downhole measurement and control system is proposed.This design through the analysis of the existing structure of videolog downhole TV,puts forward the scheme of extending the control module based on videolog downhole TV.Firstly,based on the P2 P network communication,the serial port transparent transmission between the host computer and the underground network encoder is established.Secondly,the serial port of network encoder is extended and connected with the main controller.The main controller is the communication control core of the measurement and control system.Then,using 485 bus structure and Modbus protocol,the hardware structure requirements and data communication requirements of multi parameter modular expansion are realized respectively.Finally,according to the operation characteristics of videolog underground TV,four basic measurement and control modules,including temperature measurement,pressure measurement,dimming and rotation,are expanded.Videolog underground measurement and control system is mainly composed of upper computer,underground main controller and underground measurement and control module.The upper computer is mainly used to receive and display the measurement parameters in real time,and can also send control instructions to the control module.Based on STM32 and RS485 bus,the underground main controller realizes the expansion of measurement and control module and the transmission of measurement and control parameters.The downhole measurement and control module enriches the functions of the instrument and embodies the expansibility and reliability of the system.The test results show that the system can provide the extension interface for videolog downhole TV from hardware,for different measurement and control modules to expand,and establish reliable data communication from software,and the extended module can normally realize its proper measurement and control function.