Fire behavior of mining vehicles in underground hard rock mines

The results from a number of investigations and fire experiments are presented and analyzed in order to characterize the fire behavior of mining vehicles in underground hard rock mines. The analysis also includes fire safety and fire protection measures with respect to the mining vehicle fire behavior.Earlier studies on fires in underground hard rock mines have shown that vehicles or mobile equipment are the dominant sources of fire. A better knowledge about the fire behavior of vehicles in underground hard rock mines is therefore needed. During the analysis the direction and flow rate of the ventilation in a drift was found to have a significant impact on the fire behavior, causing for example flame tilt with rapid fire spread. The shielded sections of a vehicle will be less affected by the ventilation flow resulting in for example a decreased flame spread. It was also found that spray fires may result in considerable heat release rate but are generally of shorter duration and will not make any significant contributions to the overall heat release rate of the fully developed vehicle fire. The fire duration of a loader tire from a full-scale fire experiment was found to be at least 200 min and will largely determine the total fire duration of the vehicle. A different scenario with different conditions with for example a slower flame spread resulted in an even longer fire duration. The radiative and convective fraction will be a key factor when determining the heat transfer mechanisms involved in a fire and will vary from material to material.Calculations show that the radiative fraction of the tire fires on two mining vehicles is significantly lower than found in earlier experiments. The design and construction of the mining vehicle will have an important impact on the fire behavior and could possibly mitigate the consequences of a fire and allow fire personnel to extinguish a fire that otherwise would have had a too high heat release rate.

A Study on the Dynamic Analysis of A Tracked Vehicle for Ocean Mining on the Deep Seabed

A study is presented on the dynamic analysis of a tracked vehicle for mining on the deep seabed of very soft soil. Equations for the interaction between the track and extremely soft seabed are employed to develop a track/soil interaction module called TVAS. The vehicle is modeled as a multibody dynamic system by the use of a multibody dynamic analysis program. The module developed is cooperated with the multibody dynamic analysis program with a user-defined subroutine. The dynamic behavior and the conceptual design of the mining vehicle on the deep seabed are investigated.

Vibration Performance Analysis of a Mining Vehicle with Bounce and Pitch Tuned Hydraulically Interconnected Suspension

The current investigations primarily focus on using advanced suspensions to overcome the tradeo design of ride comfort and handling performance for mining vehicles. It is generally realized by adjusting spring sti ness or damping parameters through active control methods. However, some drawbacks regarding control complexity and uncertain reliability are inevitable for these advanced suspensions. Herein, a novel passive hydraulically interconnected suspension(HIS) system is proposed to achieve an improved ride-handling compromise of mining vehicles. A lumped-mass vehicle model involved with a mechanical–hydraulic coupled system is developed by applying the free-body diagram method. The transfer matrix method is used to derive the impedance of the hydraulic system, and the impedance is integrated to form the equation of motions for a mechanical–hydraulic coupled system. The modal analysis method is employed to obtain the free vibration transmissibilities and force vibration responses under di erent road excitations. A series of frequency characteristic analyses are presented to evaluate the isolation vibration performance between the mining vehicles with the proposed HIS and the conventional suspension. The analysis results prove that the proposed HIS system can e ectively suppress the pitch motion of sprung mass to guarantee the handling performance, and favorably provide soft bounce sti ness to improve the ride comfort. The distribution of dynamic forces between the front and rear wheels is more reasonable, and the vibration decay rate of sprung mass is increased e ectively. This research proposes a new suspension design method that can achieve the enhanced cooperative control of bounce and pitch motion modes to improve the ride comfort and handling performance of mining vehicles as an e ective passive suspension system.

Predicting the sinkage of a moving tracked mining vehicle using a new rheological formulation for soft deep-sea sediment

The sinkage of a moving tracked mining vehicle is greatly af fected by the combined compression-shear rheological properties of soft deep-sea sediments. For test purposes, the best sediment simulant is prepared based on soft deep-sea sediment from a C-C poly-metallic nodule mining area in the Pacific Ocean. Compressive creep tests and shear creep tests are combined to obtain compressive and shear rheological parameters to establish a combined compressive-shear rheological constitutive model and a compression-sinkage rheological constitutive model. The combined compression-shear rheological sinkage of the tracked mining vehicle at dif ferent speeds is calculated using the Recur Dyn software with a selfprogrammed subroutine to implement the combined compression-shear rheological constitutive model. The model results are compared with shear rheological sinkage and ordinary sinkage(without consideration of rheological properties). These results show that the combined compression-shear rheological constitutive model must be taken into account when calculating the sinkage of a tracked mining vehicle. The combined compression-shear rheological sinkage decrease with vehicle speed and is the largest among the three types of sinkage. The developed subroutine in the Recur Dyn software can be used to study the performance and structural optimization of moving tracked mining vehicles.

GPS/GIS based vehicle dispatching for opencast mines

An integrated GPS and GIS based vehicle dispatching system was presented. The system uses GIS technology for the development of digital mine map database and GPS for vehicle positioning. The system consists of five modules: position module incorporated GPS and dead reckoning (DR); a map database structure for displaying and guidance purposes; a routing module based on the map database is able to give out the best route for the vehicles; map matching and route guidance module put the vehicle position to its exact location on the road despite of errors in positioning and map data; and the client-server module allows client exchange information between driver and control centre. The system can be operated in client-server level in which users can request routing and guidance with devices such as hand phone and PDA by communicating their current positions to the server or runs in autonomous mode when users cannot reach the server.

Obstacle performance of cobalt-enriching crust wheeled mining vehicle

A cobalt-enriching crust mining vehicle with four independent driven wheels was proposed. The influence of center-of-gravity position of mining vehicle on obstacle performance was studied. The results show that the mining vehicle has optimal obstacle performance with center-of-gravity position in the middle of suspension. A virtual prototype based on ADAMS software was built and its obstacle performance was simulated. Simulation results show that the mining vehicle with four independent driven wheels has excellent obstacle performance, the maximum climbing capacity is no less than 30°, the maximal ditch width and shoulder height are no less than wheel radius of mining vehicle. Thus wheeled mining vehicle is feasible for cobalt-enriching crust commercial mining.

Long-term economic sensitivity analysis of light duty underground mining vehicles by power source

LHD's are expensive vehicles; therefore, it is important to accurately define the financial consequences associated with the investment of purchasing the mining equipment. This study concentrates on longterm incremental and sensitivity analysis to determine whether it is feasible to incorporate current battery technology into these machines. When revenue was taken into account, decreasing the amount of haulage in battery operated equipment by 5% or 200 kg per h amounts to a $4.0 × 10~4 loss of profit per year. On average it was found that using battery operated equipment generated $9.5 × 10~4 more in income annually, reducing the payback period from seven to two years to pay back the additional $1.0 × 10~5 investment of buying battery powered equipment over cheaper diesel equipment. Due to the estimated 5% increase in capital, it was observed that electric vehicles must possess a lifetime that is a minimum of one year longer than that of diesel equipment.

A Predictive Energy Management Strategies for Mining Dump Trucks

The plug-in hybrid vehicles(PHEV)technology can effectively address the issues of poor dynamics and higher energy consumption commonly found in traditional mining dump trucks.Meanwhile,plug-in hybrid electric trucks can achieve excellent fuel economy through efficient energy management strategies(EMS).Therefore,a series hybrid system is constructed based on a 100-ton mining dump truck in this paper.And inspired by the dynamic programming(DP)algorithm,a predictive equivalent consumption minimization strategy(P-ECMS)based on the DP optimization result is proposed.Based on the optimal control manifold and the SOC reference trajectory obtained by the DP algorithm,the P-ECMS strategy performs real-time stage parameter optimization to obtain the optimal equivalent factor(EF).Finally,applying the equivalent consumption minimization strategy(ECMS)realizes real-time control.The simulation results show that the equivalent fuel consumption of the P-ECMS strategy under the experimentally collected mining cycle conditions is 150.8 L/100 km,which is 10.9%less than that of the common CDCS strategy(169.3 L/100 km),and achieves 99.47%of the fuel saving effect of the DP strategy(150 L/100 km).

Deep-sea rock mechanics and mining technology:State of the art and perspectives

The review covers the development and the state of the art in deep-sea mining rock mechanics,equipment and challenges.It begins by introducing the significance of deep-sea mining,the types and geographical distribution of deep-sea resources.Section 2 reviews the mechanical properties and fracture mechanism of seabed and related continental rocks,which contributes to the advancement of relevant technologies and theories.Deep-sea mining systems developed by coastal countries are presented in Section 3.Seabed mineral collection systems are critically assessed in Section 4.Subsea mining vehicle is reviewed by walking mechanism and controlling system in Section 5.In Section 6,the development of subsea lifting system is detailed by dividing it into hydraulic and pneumatic lifting modes,and some technical problems in the lifting system are described.An in-depth description of surface support systems is presented in Section 7,which includes the deep-sea mining ship,dynamic positioning system,heave compensation system,launch and retrieval system,mineral disposing system as well as the storage and transferring systems.Section 8 discusses the challenges in the deep-sea mining,in terms of natural occurrence conditions,international legal framework and cooperative mining,environmental protection and economic benefits,etc.Finally,a brief summary and some aspects of prospective research are presented in Section 9.

Trace Interpolation Algorithm Based on Intersection Vehicle Movement Modeling

Real vehicle tracking data play an important role in the research of routing in vehicle sensor networks. Most of the vehicle tracking data, however, were collected periodically and could not meet the requirements of real-time by many applications. Most of the existing trace interpolation algorithms use uniform interpolation methods and have low accuracy problem. From our observation, intersection vehicle status is critical to the vehicle movement. In this paper, we proposed a novel trace interpolation algorithm. Our algorithm used intersection vehicle movement modeling (IVMM) and velocity data mining (VDM) to assist the interpolation process. The algorithm is evaluated with real vehicle GPS data. Results show that our algorithm has much higher accuracy than traditional trace interpolation algorithms.

基于前馈补偿LQR与PID的矿井无轨胶轮车横纵向控制研究

无人驾驶技术是实现无轨胶轮车井下安全、智能、高效运输的重要方案之一,为了提高无人驾驶过程中的轨迹跟踪精度,提出了基于前馈补偿的横向线性二次型调节器(Linear Quadratic Regulator,LQR)与纵向比例积分微分(Proportion Integration Derivative,PID)位移速度调节器相结合的控制策略,实现车辆的横纵向协调控制。通过建立考虑轮胎侧偏特性的2自由度无轨胶轮车动力学模型和跟踪误差模型,并采用井下无轨胶轮车实车参数建立其电机模型,得到车辆的驱动制动输出。利用Carsim和Matlab/Simulink搭建联合仿真环境,分别在井下双车道工况、单车道工况与颠簸路面工况下进行了轨迹跟踪仿真验证。结果表明:在3种工况下车辆轨迹跟踪过程中的最大横向误差仅为5 cm,最大纵向误差仅为10 cm,速度误差控制在1 m/s以内,航向误差范围为±0.1 rad,前轮偏转角变化平稳未出现抖动现象。为验证控制器在井下实际环境下的跟踪性能,使用实验室小车于陕西某井下巷道进行了现场试验验证,结果表明:井下实际巷道下试验结果误差仍在合理范围内,解决了车辆运行过程中的速度和路径的时变问题,反映出该控制器具有较高的精度和较好的稳定性。

基于Burger’s蠕变模型的采矿车行驶海底稀软底质下陷研究

在陆地矿产资源日渐枯竭的今天,深海矿产资源已成为全球各个国家争相开采与利用的焦点,深海采矿车是实现深海矿产资源开采的重要装备。海底稀软底质是一种承载力与抗剪强度极低的特殊底质,在采矿作业中,深海稀软底质的物理力学特性直接影响采矿车行走的稳定性。文章选取Burger’s接触模型作为深海稀软底质的本构模型,对某海域海底稀软原状土开展室内三轴试验,通过PFC3D颗粒流数值模拟实验对比实际三轴试验,对稀软底质的Burger’s蠕变模型进行参数标定,同时依据标定结果改变相应参数,针对5种不同底质条件的工况,建立海底采矿车的数字仿真模型,模拟各工况下采矿车在不同行驶速度时的下陷深度。结果显示,下陷深度会随行驶速度呈非线性变化,在一定范围内随着行驶速度的增大而减少并逐渐趋于稳定。同时结果还表明,该区域海底稀软底质具有更高的黏粒含量(38.1%~48.4%)、含水率(88.13%~137.79%)和压缩性(压缩系数:1.86~3.73 MPa^(-1),压缩模量:1.26~2.13 MPa),具有更低的密度(1.3~1.5 g/cm^(3))和强度特性(贯入阻力:0.19~1.32 N,黏聚力:3.7~6.9 kPa,内摩擦角:2.4°~3.9°),即承载力较低,蠕变性能较强。本研究在宏观上做了一般的探讨,为类似参数的稀软底质下海底采矿车的运行安全控制提供了较好借鉴与依据。

深海采矿系统模型水池试验方案

深海采矿系统单一模块研究无法准确反应其实际运行特性。搭建深海采矿系统模型水池试验平台,分析深海采矿系统运动力学特性,提出深海采矿系统模型全流程水池试验方案,为深海采矿系统全流程模拟提供技术支撑。

大数据分析管理系统在新能源汽车事故分析中的应用

随着新能源汽车的广泛使用,新能源汽车事故数据的分析处理越来越受到人们关注。传统的事故数据分析方式通常需要大量的人力和时间,而且往往只能分析少数的数据变量。数据挖掘技术以其强大的数据分析和挖掘能力,已经在新能源汽车事故数据分析处理中得到广泛应用,以帮助研究人员从事故数据中挖掘出潜在的规律和特征,为事故原因和解决方案的提出提供科学依据。本文设计了一套新能源汽车事故大数据分析管理系统,更加高效、有规律地分析新能源汽车事故数据。

煤矿辅助运输防爆车辆电动化和数智化的应用研究

为提升煤矿辅助运输智能化建设水准,神东煤炭集团构建了辅助运输车辆管理系统。文章介绍了构成系统的主要模块,并基于井下人员和车辆的定位系统,利用井下4G/5G网络和巷道基站将信号传输到每个矿井地面调度室,然后通过光纤传输到大数据中心,实现了车辆监管数字化,让用车、派车更便捷。介绍了辅助运输车辆车载辅助安全驾驶系统、启动预警系统、智能感应自动停车装置、空挡启动保护装置、无线视距遥控等智能化技术。该系统利用激光雷达和相机对巷道扫描建模,为无人驾驶车辆提供“地图”,采用毫米波雷达技术和机器视觉技术实现辅助运输车辆在井下的精确定位,实现了无人驾驶的常态化运行能力。神东辅助运输车辆的电动化、监管数字化和智能化,极大的提高了辅助运输的安全和效率,提升了煤矿智能化建设水平。

基于MPC算法的深海采矿车轨迹跟踪控制

针对深海采矿车在海底行走作业时受到复杂环境影响而偏离预定路径问题,提出基于模型预测控制(MPC)算法的轨迹跟踪控制器。利用深海采矿车运动学模型在Matlab中进行数值仿真分析,利用深海采矿车多体动力学模型开展Matlab-RecurDyn联合仿真分析。仿真结果表明,在直线与曲线工况下轨迹跟踪控制器都有较好的跟踪效果,并且联合仿真比数值仿真的结果更加符合真实环境。

改进Retinex-Net的露天矿低质图像增强算法

露天矿低质图像增强是无人驾驶宽体车感知系统的重要环节,单目相机获取的图像易受到矿区粉尘、雨雪雾、剧烈震动等多种因素影响。针对传统图像增强算法在处理露天矿图像时存在噪声大、图像颜色失真等问题,提出了改进Retinex-Net算法对露天煤矿图像进行增强。使用循环对抗生成网络和双通道残差网络来改进增强和去噪部分。循环对抗生成网络通过学习低光照图像和正常光照图像之间的映射关系,生成更自然和真实的增强结果。双通道残差网络通过同时处理亮度和色度信息,有效去除低光照图像中的噪声和伪影。试验结果表明:该方法在客观和主观评价指标上均优于现有方法。所提改进Retinex-Net算法为解决露天矿图像质量问题提供了一种有效方案。

基于深海钴结壳采矿车的路径规划方法研究

针对目前深海钴结壳采矿车在采矿时无法达到规划时间和路程代价综合最优,提出一种改进的跳点搜索算法作为全局路径规划算法。首先,基于对采矿车越坡动力学的分析,模拟了具有不同坡度的结核矿区栅格地图,并利用动态跳点搜索算法完成路径规划;其次,采用贝塞尔曲线来平滑路径以减少和优化转弯角度,并设定了最小转弯半径约束以减小采矿车的转弯频率;最后,通过仿真结果表明,改进后的跳点搜索算法相较于其他4种算法,在规划时间上缩短了40%,在规划路径长度和平滑度方面得到5%和10%的提升,相较于单向跳点搜索算法在探索效率上得到较大提升,最终证明了该算法在路径规划时的实时性和路径规划能力的优异性。

融合机载LiDAR与摄影测量技术在矿山迹地修复中的应用研究

随着矿产资源的大力开发利用,出现一系列资源枯竭、环境污染、生态破坏的问题,使得矿山生态环境快速、有效的修复治理成为我国生态文明建设中重点关注的问题。然而,传统作业方法在环境恶劣的山区地形测绘中存在作业盲区多、难度大、成本高且安全隐患大等问题。因此,本文融合机载激光雷达和摄影测量技术从空中获取到矿山迹地完整、高精度的三维激光点云数据与高分辨率影像数据。再经过数据融合与后处理生成高精细数字高程模型以及各类专题图成果,在矿山迹地修复规划中林木资源调查、填挖方量计算、地形地貌变化分析及安全风险评估等各项工作中提供有力的技术与数据支持。

安徽某地下矿山移动智能安全巡检车设计

为了落实我国《“互联网+”人工智能三年行动实施方案》和《新一代人工智能发展规划》精神,推进重点领域智能产品创新应用和试点示范,推动人工智能技术规模化应用,提出在移动车辆平台搭建智能巡检管理系统,对巷道进行全线路、全方位、全自主智能化巡检管理,实现智能化巡检、可视化管理,进而提高地下矿山生产的安全性,避免因人工巡检不全面、不量化、人员素质依赖性强导致的各种安全事故与损失。