Designing Of Biaxial Stress Monitoring System In Coal Mining Field

The project presents a more desirable method of coal-stress-monitoring based on the disadvantage which is shown by the stress monitoring equipments which are being used in Chinese coal mines at present. This project has upgraded the single sensor that is widely utilized in coal mines all over the country to biaxial sensor which is able to pick stress values in two-dimensional space. More closer to the realistic situation of stress has been reflected by the biaxial sensor. The one-way valve that is added to the peripheral auxiliary equipment of the new sensor has reduced complexity of the pump. Overall, the biaxial sensor makes the installing preparations of monitoring equipment more simpler.Hierarchical controlling method is applied to the project. The main station commands are sent to sub-station and the values picked are sent back to main station. The whole system is controlled by the microcontroller AT89S52, which shows excellent performance in industrial applications. In order to achieve better filtering effect, the chip MAX260 is applied to the project. The stress value picked is enlarged to the amplitude required by the way of two-stage amplification. Meanwhile, the infrared communication is embedded into the system in order to increase flexibility of the system. The system can also alarms by sound and light so that the field staff have as much time to take appropriate protective measures when accidents occur in the coal mine.