地下开采自动化策略.doc

Strategy of Automation for Underground MiningAbstract - There are objective preconditions for computerintegrated mining, such as deep mines and dangerous conditions of work. Future mining will be based on underground machines that. H!ill be controlled from surface. The paper is -aimed to consider the sequence of automation towards computer integrated mining.System an operator on surface - a set of underground machines is simulated by GPSS/H as a mass service system. Decision-making for loading and transporting of useful minerals is simulated by Petri nets. Use of on-board RFID for mine planning is suggested. Some applications of mine robotics, mine simulation and animation, multi-agent mining are analyzed in the paper. Cost-effectfor mine automation and milestones to intelligent mine are considered in the paper.1. IntroductionOre deposits that were suitable for traditional mining are almost exhausted already. The deeper a mining is, the more dangerous, more unpleasant, and more expensive miners work is. Employer loses a lot of money to transport miners for underground work. It is difficult, to co-ordinate mining actions in space and time. The following strategies of unmanned mining could be realized: undergroun.d dilution of useful minerals;substitution of miners by remote-controlled manipulators;control of underground machines from surface.The first strategy is ecologically dangerous. The second strategy will maintain traditional mining that was oriented on limited mens possibilities. Besides, it will be necessary to present the full information about working conditions for an operator. That is why, the third strategy is more perspective for mining. Unfortunately, mining is found on the last place to master new ideas of factory automation. Both changing environment and conservatism of mining engineers create obstacles to using of modem automation. The long-term dream of people is - to realizeunderground mining without underground miners. Future mining will be based on underground machines that will be controlled from surface (Fig. 1)All of machines are connected by information network,that is connected with a control room on surface 1. The machine has TV-cameras and system ofautomatic control. As a rule, on-board system takes routine control actions such as movement in roadway, whereas operator takes intellectual actions such as scooping of rock mass. Thus an operator can control of many machines. It is necessary to create the following sub-systems for the strategy:information network to transmit a voice, data, and video information in real-time mode between underground machines and surface;man-machine interface for a control of underground machines from surface;machines;software for both current and strategic mine planning;navigation and positioning of autonomous machines in roadways. creation of special technologies for tele-mining.2. Underground mining as the computer integrated systemLets present Intellectual Mine as five-level Computer Integrated Mining (Fig. 2).I/O-level presents distributed Input/Output- signals as the common signals for a programmable logic controller on Control-level. One ensures a galvanic division, normalization of signals, protection against doubleclicking.SCADA-Ievel presents a current mining foranalysis, keeps current data, recognizes pre-emergency situations, derives new data for strategic planning, recommends consecutive actions in emergency situation. MES-Ievel ensures current mining by comparison of costfor distributed mining areas, full utilization of equipment,revelation of bottlenecks, distribution of materials. MRP-Ievel changes the strategy of mining according tosituation on a world market.3. Results of research3.1. Distribution of controlLoading-Haulage-Dumping machines (LHD) is the basis for underground ore mining. How many LHD can be controlled by an operator from surface? The problem was described in 2,3. Lets present a system operatorsmachines as the closed system ofmass service (Fig. 3).Each of machines can have three states: I-remote control from surface; 2-automatic movement betwee:n loading and dumping places; 3- waiting in a queue before remote control. The behavior of the system was simulated by GPSSIH. During simulation a number of machines and a part of automation actions or distance of haulage were changed, then utilization of operator was evaluated.The results of simulation show, after 40% of automaticactions a single operator can control of 3-5 machines(Fig.4). The same result was received after the simulation by Extend 6.0.After that a system N operators - L machines was simulated to compare two modes of control: released operator takes the any first machine from a queue,released operator takes the assigned to him first machine from a queue . The first mode was evaluated by N=3,L=7, whereas the second mode was simulated by three mass service systems MIMI. It was established, a difference in productivity for both modes is less than 5 %. That is why, it doesnt matter what kind of mode will be better to increase the productivity ofa system. 3.2. InteUectualloading After a scooping the fillnes of a LHDs bucket is random. What a strategy is more productive during a working shift: to reiterate scoopings up to full bucket (5-6 times for manual control) or to finish loading if a bucket is not enough full? The bucket filling must be measured to finish a loading by LHD during remote control:K = (T m + Ts ) / Tm + Ts + (1 - P) nT where K=grade of bucket filling; Tm= movement duration;1S=scooping duration; P=probability of a scooping repetition; n=number of repeated scooping till full bucket;Tis = average duration of a scooping.The technology was simulated by Petri net with experimental data 4. During a simulation a given payload k was changed till 1.000 with the step 0.025. Shift productivity was calculated for every value. It appears, the shift output has a maximum (790 t) if bucket payload is 65% at any rate for haulage length 45 m and scooping time lOs (Fig. 5). That is 17% more than one for reiteration of scooping up toa full bucket for the first strategy.Intellectual sensor of bucket filling can form a signal to finish a loading for the actual haulage length. 3.3. Tele-controlled machine as a medium source RFID - systems were developed recently to write, store, and recognize information about the product during its manufacturing and transporting. It is necessary for mine planning, to know, how many ore mass was extracted from each face. The problem is - how to introduce data from moving LHD into stationary information network? The bucket filling by on-board sensor 5 is evaluated before departure of LHD to a dumping place (Fig. 6).The results are transferred to on-board transponder 1 for keeping. When LHD passes by antenna 2, the on-board data are introduced into information network by controller 3 and writing/reading device 4 5. Besides, RFID can be used to visualize the placement of machines inside roadways; to monitor miners with personal transponders; prevent non-permitted control of machines; give a priority for a control of machines; evaluate a productivity of both machines and mining areas; evaluate a fuel consumption and machine resources.3.4. Mine RoboticsUnderground machine with semi-automatic control has the main sign of a-robot - reprogrammable 0 movement of a multi-purpose working head 6. That is why, such machine can adapt itself to changing working conditions.For example, LHD can change a trajectory of bucket movement according to a random pale fonn.3.5. Mine simulation and animationDispatcher uses simulation of real mining to support his decisions-making. He tested his decisions as What if. . ?-experiments by a dynamic model of mining in rapid time 7. After a selection of the best decision a dispatcher comes back to real mining. The idea was tested for a real underground mine Komsomoletz with conveyors and trains (Fig.8 ).Coal flows are transported by two conveyor lines from faces to loading points LP1 and LP2. A dispatcher must direct an empty train to one of two loading points. If his decision is wrong, transfer bunkers in conveyor line are overfilled and faces that are connected with the line must be stopped. The transporting was simulated by timed Petri net, that consists of 50 positions and 45 transitions. With the help of simulation a dispatcher can change a number of trains, state and output of any face, forecast filling of bunkers in rapid time according to real situation, anddirect a train to right loading point.4. Cost-effectA control of underground autonomous machines from surface will improve mining by realization a mining of deep deposits, shortening a number of underground miners, ensuring of a miners safety, shortening time losses for a moving between surface and working place, planning of mining in real time, planning of equipment maintenance accordig to aLwork, changing of miningsequence from surface, acquisition of new knowledge about mining, such as fuel expense, working reserve, current cost in various areas, and state of a machine stock, exchange of voice, data, and video information between underground equipment and surface, shortening of machines downtimes. Any automation technology canbe characterized by annual output, Q; , equipment cost, Ki, utilization period N;, and annual outlay on labor force Z;, materials and energy Cr The ratio of a total production volume Q;V; to total expense on automationPi(Ni) = Qi Ni/Ki+Ni(Ci+Zi)reflects, how perfect a mining technology is. One can be evaluated for the old technology ( with indexes 0 ) also.Specific application of automation is profitable if5. Towards an intellectual miningUnderground automation will be developed step by step via the following milestones:telemanipulators for mechanization of manual works;operator alternatives remote control and automatic control of telemanipulator under direct visibility, then control from a surface is obtained