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HAULAGE ETF's futuristic-looking 240-ton-capacity mine truck features a four-engine power pack behind the cab, and 10 in- dependent axle units. Individual axle units can be lifted during empty hauling or in case of a flat tire. "To be able to carry out this MARC work properly we will build a workshop on site at the customers mine and do the work," he said. "It gives confidence to the client that the factory itself is doing the [mainte- nance] of his new trucks. The only issue is that we cannot do this for one or two trucks, the minimum is 10 trucks." de Jongh said the first three ETF units to go into a production environment would be shipped to an iron ore producer in Brazil at the end of August 2012. The basic layout of the ETF haulers, as illustrated in a PowerPoint presentation pro- vided by the company, represents a mind- boggling departure from conventional design practices; in fact, about the only familiar concepts displayed by the ETF units are a cab and a dump body—and even the cab layout differs from the norm by hav- ing a center-positioned operator's seat flanked by 'trainer' seats on each sides. Power comes from four independent engines stacked in a "power pack" module behind the cab. Only one of the four MTU/Mercedes-Benz OM-502, 480-kW Tier III engines is used during empty trav- el, two or three engines are in use during loaded hauling and the fourth engine comes on line when full power is required while hauling on grade. In the event that one engine develops a problem or fails, the truck can continue to operate with the remaining engines, returning to the work- shop where the failed engine can be removed and replaced with another modu- lar unit in 15 minutes, according to ETF. Modularity also extends to the tires and suspension, which on ETF's MT-240 model include 20, 24.00R35 tires mounted in dual-wheel groups on five axles per side, with four axle units per side driven and one non-driven. In the event of a flat tire, the individual axle unit can be lifted off the ground, preventing further tire damage; and the non-driven axle units also are lift- ed during empty operation. Each of the 10 axle units allows the wheels to oscillate 10° side to side. This design, according to Homing In on the Human Factor in Haulage Risk Reduction Production haulage is a critical link in the mining sequence, but even under the best of conditions it's a repetitive task that often involves long distances and extended work hours. Combine those ingredients with the size, weight and speed of the machinery involved, along with the constant vibration, noise and limited visibility experienced by operators, and it's easy to see why most surface mining accidents involve mobile equipment engaged in hauling activities. But, regardless of the specific vehicle type or activity—it could be a haul truck, a wheel loader, a service truck or even an employee's personal vehicle—fleet owners have come to realize that accidents largely stem from factors that directly involve and affect the operator, such as fatigue, dis- traction or simple unawareness. In recent years, a number of mineral producers as well as commercial and academic organi- zations have taken a closer look at ways to identify, warn and to whatever extent pos- sible, eliminate these human-factor haz- ards from their mobile equipment opera- tions. The results of this increased level of attention include a number of new tech- nologies that attack the problem from dif- ferent aspects. Switzerland-based SAFEmine Ltd., for example, has developed a mine traffic- awareness system that uses a combination 84 E&MJ; • JUNE 2012 of GPS technology and vehicle-to-vehicle communications to determine the exact location of a SAFEmine-equipped vehicle and to indicate the position of other vehi- cles in the immediate surrounding area, with coverage extending in all directions starting about 2 m from the vehicle out to 500 m. In addition, the system calculates nearby vehicles' paths using a proprietary algorithm and warns the driver of each equipped vehicle of imminent vehicle- movement or proximity situations that could pose a hazard. In practice, the dashboard-mounted SAFEmine unit displays a compass-like arrangement of indicator lights. When the system detects a vehicle in proximity, it illuminates the appropriate indicator lights to show the driver the relative position and distance of the detected vehicle(s). An alarm will sound if the system predicts that a potential collision is imminent and will continue to sound until the collision threat abates. The indicators will show green, then red and then will flash as the vehicle nears another vehicle. The SAFEmine sys- tem optionally can provide voice notifica- tions that inform the driver of the type of vehicle detected; it also can be used to announce traffic-condition alerts such as speed zones or stop signs. It will also dis- play lighted indicators on the compass dial when an equipped vehicle approaches a selected object at a predetermined loca- tion, such as a power line. SAFEmine units, taking advantage of the options available, can be configured in a variety of ways, ranging from basic prox- imity detection and collision alarm func- tions, to obstacle detection, personnel detection, local hazard alarms, live track- ing, and event recording through stored log files. Their functionality extends beyond SAFEmine's traffic awareness system. (Continued on p. 86) www.e-mj.com