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layout and markup functions for under- ground surveying, and allows features such as over- and under-break to be displayed. Leica's airborne sensors can be tied in with products from another Hexagon com- pany, Z/I Imaging (formerly Zeiss), which has 80 years of experience in producing systems for airborne photogrammetry. Leica's airborne Lidar (light detection and ranging) instruments can also produce high-definition bare-earth digital elevation models that can be used for applications as diverse as identifying exploration targets beneath thick vegetation and monitoring mine-induced subsidence. The company cited the example of a British Columbia, Canada-based company that specializes in subsidence monitoring using its ALS-70 Lidar scanner, which, it said, has a 100-mm (4 in.) vertical accu- racy and is one of the few airborne laser scanners with the power and multipulse capability required for mining applications. Locata: Local Positioning Networks CEO Nunzio Gambale told E&MJ; that Australia-based Locata Corp. has invented a new technology that creates local terres- trial positioning networks. These provide a high-precision GPS-style positioning, navi- gation and timing (PNT) capability that is completely independent of satellite sig- nals, he said. Not only does this provide extremely accurate and reliable GPS-like services but it simultaneously resolves many satellite- based PNT shortcomings, Gambale added, including the ability to reach areas where GPS is degraded or denied. Open-pit mining has been an eager early adopter of Locata, he said. With drill rigs needing better than 100-mm (4 in.) accu- racy to achieve effective controlled drilling automation, mines have attempted to use GPS receivers using standard survey-grade techniques. However, this approach becomes less effective as the pit depth increases, since satellite-only receivers can- not calculate an accurate position when too few satellites are available. To solve this problem, Leica Geo- systems has developed the world's first GPS+Locata receivers for use in open-pit mines, tracking both GPS and Locata sig- nals simultaneously. This provides centi- meter-level machine positioning, even when RTK (real-time kinematic)-GPS fails completely, Gambale stated. Locata reported that Newmont's Boddington gold mine in Western Australia was the first in the world facility to deploy a Locata-enabled Jps network. Giving almost 100% RTK-GPS level positioning availabil- ity without relying only on satellite signals, the Locata-enabled Jps has fundamentally changed the way the mine operates its fleet machine automation system. Even during a recent major satellite outage, which totally disrupted the RTK base stations and rendered survey-grade GPS unavailable, Locata kept delivering centimeter-level positioning in the pit. The company cited a Boddington fleet manager as stating pub- licly "that there is no way we would go back to a GPS-only world again." Total Stations from Topcon While much of the focus is understandably on the larger scale of things, there remains a real need for "traditional" types of survey equipment that can be used for site-spe- cific and underground surveying. Most of the world's manufacturers of survey equip- ment include this type of instrument in their product portfolios, albeit considerably more sophisticated technologically than the theodolites and levels that Young was familiar with in the early 1900s. As an example, Topcon Positioning Systems offers its DS series of compact, auto-tracking total stations, designed for one-man operation in tasks such as volume surveying and setting-out. The DS includes an electronic distance-measurement system with a range of up to 1,000 m (3,280 ft), while the operator can control the instru- ment remotely from the prism pole, up to 300 m away. Auto prism tracking is also available as an option. Perhaps designed with mining and exploration in mind, the instrument's IP65 waterproof cover helps exclude dust and driving rain, while the instrument itself can be used in temperatures from –20°C to 50°C. Security is also built into the DS series, Topcon added, with its inbuilt TSshield communications module including a fea- ture that enables an instrument to be dis- abled remotely if it is lost or stolen. Data handling and manipulation is done using Topcon's Magnet software in both the field and the survey office, with data download via a USB port. Riegl: Laser Scanners The Austrian surveying equipment manu- facturer, Riegl, used the last MINExpo in Las Vegas to launch its VZ-6000 laser scanner. Designed for ultra-long range applications in topography and mining, the JULY 2014 • E&MJ; 29 www.e-mj.com M A P P I N G & S U R V E Y I N G A Reigl laser scanner in use at AngloGold Ashanti's Geita mine in Tanzania. (Photo courtesy of 3D Laser Mapping). One-person operation with a Topcon DS total station. EMJ_pg28-31_EMJ_pg28-31 7/1/14 11:46 AM Page 29