Detection and self-healing of cluster breakages in mines and tunnels: an empirical investigation

Abstract

Purpose -The study aims at providing a reliable system of real-time monitoring for underground mine and tunnels which detects any structural change in the network and reconfigures it for resuming the data delivery process. In high stress environments, e.g. underground mines and tunnels, real-time activity monitoring is an emerging issue. Wireless sensor networks (WSNs) play a key role in ensuring the safety of people working in underground mines and tunnels. WSN not only provide real-time monitoring of underground environment but also detects any structural change in the network itself. Design/methodology/approach -In this paper, results of empirical implementation of a re-configurable WSN, capable of self-healing approach, reconfigure the network connectivity upon failure or addition of nodes in the system. An open-source radio-frequency identification standard for WSN, named as DASH7, is used for practical implementation. The proposed system is capable of determining cluster breakage by sudden disruptions caused by roof falls, explosions and node failures, sensor coverage hole, node re-addition to the network and distress priority signal generation by the miner. Findings -The proposed platform contributes to re-attain network state for establishing a communication link with fusion center in terms of: instant and accurate detection of collapse holes, acceptable error rate, time to re-attain network state, rapid distress signal propagation and low deployment cost. This platform is deployed in four different environments of anechoic chamber, hallway, outdoor and underground mine environment, to test the aforementioned scenarios using DASH7-compatible Bitsense Sensor Motes operating at 433 MHz. The effectiveness of the proposed approach has been experimentally validated for the single and multiple adjacent and disjoint node failures in all the four environments. Originality/value -The number of monitoring systems was implemented for safety assurance in high stress environments before, but the novelty of our platform is long range, cost effectiveness, quick response to any structural change in the network, rapid and accurate data delivery using WSN operated on DASH7 protocol stack.

Gray algebraic curve model-based roof separation prediction method for the warning of roof fall accidents

“…Salient findings of field instrumentation data analysis such as mining-induced vertical stress development over the pillars, load over the support, roof separation at different horizons, and convergence of roof in rooms with face advance were presented (Satyanarayana et al 2015). Khan et al (2015) use wireless sensor networks to determine cluster breakage by sudden disruptions caused by roof falls. Xie and Xu (2015) took ground-penetrating radar (GPR) as a means for roof separation detection and analyzed its feasibility for use in detecting roof separation both theoretically and experimentally.…”

Target infrared radiation calculation model and method based on finite element analysis method in infrared photoelectric detection system

“…Zhang et al (2008) analyzed flight target’s radian characteristic and gave the calculation function of target’s surface radiant energy, but, those reference documents do not analyze other factors effect to detection system, such as, the changing illumination under different background environment, the target optical characteristics and the flight target radiation characteristics. In addition, some researchers has been carried out some basic research in infrared photoelectric tracking, their main research are concentrated in the photoelectric imaging detector and tracking control system (Khan et al , 2015), but, the research is relatively less that the environment factor and target characteristics affect the detection performance of infrared photoelectric detection system. So, to enhance and improve the detection ability of infrared photoelectric tracking, we must built an appropriate tracking platform, research the target optical characteristics and the target infrared radiation characteristics and deduce the detection distance calculation function, as it is very necessary.…”