Cape Hatteras Lighthouse Relocation One Man, Two Robotic System Make History A Leica TCA1103 monitors the After several hours of It turns out the engineering track roadbed. Now very settlement as the lighthouse is training, the real work system was malfunctioning, comfortable with the robotic pushed off the original wooden began. giving engineers exact system, he borrowed the timbers by five hydraulic jacks. opposite information as to second Leica TCA1103 The riggers attached two the tilt. Within an hour, system, locked onto a Leica prisms to the main shaft of Leica’s robotic system 360° prism and began recor- the lighthouse structure: one became the primary light- ding data. The surveyor was stepped in to save it. They near the bottom and one house watchdog. operating two TCA1103’s at called on surveyors, attached near the top. The the same time! engineers and a construc- riggers then cut the granite Sitting side-by-side, the tion team to move the land- substructure and began engineers controlling the It took 23 days to move the mark 2,900 feet from its transferring load to 100 lifting jacks watched the lighthouse 2,900' to its new original location and 1,600 hydraulic shoring jacks robotic LCD readout for home on a 60’ x 60’ x 4’ feet from the sea. (each capable of lifting 100 slight changes. When the concrete and steel slab, tons). Once the shoring jacks lighthouse tilted slightly, designed so the leading In summary, this required were in place, the steel they would pressurize the edge would take the entire construction crews to cut the beams and lifting jacks appropriate jack to weight of the lighthouse as lighthouse from its founda- would be inserted to lift the rebalance the lighthouse to it rolled into position. tion, raise it six feet, insert a lighthouse an additional six vertical. Throughout this six- Engineers were concerned steel support system and feet. foot lift, the robotic system about the back of the slab then hydraulically move the It’s not really the application developers had in mind when did not monitor more than tipping up as a result of the they introduced the powerful, speedy and accurate Leica lighthouse along steel tracks Prior to the move, one of the a 0.3° movement at the top weight. Leica prisms were mounted on one-man robotic survey system – nor did they envision to a new foundation. Pretty engineering firms had also prism. the top and the base of the light- that one man might have reason to operate two at the straightforward, at least in installed a $250,000 electro- By now, the surveyor’s job house and checked every day. same time. But that’s exactly what happened during three theory. nic system designed to Once lifted, the construction was to monitor the move- The black box is the housing for surprising weeks this summer on the North Carolina monitor tilt and tip of the crews installed the steel rail ment of the slab – not the the Internet site camera. shores during the historic Cape Hatteras Lighthouse Monitoring Tilt: lighthouse during the move. track beneath the lighthouse lighthouse. He propped a relocation. Robotics System #1 Its system gauges recorded foundation, shifted the free-floating, 360°-prism The Hatteras lighthouse on its structure to the track and pole on the slab so it could Clearly, a key concern inside wall temperatures steel base and seven track rails prepared for the horizontal move up and down. Once A customer of Earl Dudley throughout this process and outside wall temperatu- as its nears the new location. move. Once again, the again, locked the robotic Associates, Leica’s local would be the lighthouse’s res on the black and white robotic system was used to station on to the prism, set dealer in North Carolina, stability. Modeling systems stripes. Some strain gauges monitor tilt. Engineers it in stakeout mode and called and said he wanted to demonstrated that the 208- were set inside to measure moved the lighthouse just measured cut-and-fill try a Leica Robotic on a foot tall lighthouse could tip changes in shape and distance as the lighthouse 4 inches along the steel track quantities during the entire series of lot surveys. The in any one direction no more roundness. In addition, The Leica TCA 1103 was also inched higher. If the on the first try. They then process. According to the survey specialists at Earl than 6.5 degrees before it gauges were attached to a used to monitor the settlement as lighthouse tilted, the robotic went forward with two full surveyors, the slab never Dudley Associates sent a was in danger of serious number of the existing the lighthouse was pushed “off“, readout would display a strokes, totaling 10 feet the deflected more than Leica TCA1103 with damage or falling. cracks to see if they widened and the settlement of the new come-and-go, similar to a first day. 0.025 feet. RCS1100 to the client. After or closed. Finally, two tilt foundation as the lighthouse was traditional stakeout receiving the unit, the custo- Operating as a back-up sensors were mounted on pushed “on“ (0.1 ft on the old operation. Steel Track Alignment: Today, the lighthouse stands mer called and mentioned resource, one surveyor from the inside walls at the top wood timbers and 0.02 ft on the Robotics #2 a safe 1,600 feet from the that he was at a lighthouse a local survey firm moved and bottom. Unfortunately, new concrete foundation). About two weeks into the sea, well away from the and he needed a little help! on-site to perform necessary electrical storms, power move, near disaster shifted Besides the lighthouse dangerous erosion. For Earl analysis during the light- outages and damp weather the robotic responsibilities monitoring, the surveyors Dudley and the lighthouse Within several hours, house move. It was his job plagued the sophisticated dramatically. On this day, needed to track the survey team, the monument Earl Dudley Associates’ to closely monitor this tilt system. The system mal- computer readouts alignment of the roll beams represents an historic event Tom Dudley found himself from the time the foundation functioned and occasionally suggested the lighthouse attached to the steel rail of their own – the successful A Leica TCA1103 was used to standing next to the historic was cut until the lighthouse failed. was leaning slightly to the track from the center point operation of dual one man align the “rails“. 129-year old Cape Hatteras moved onto its new founda- left. Engineers adjusted the to the new location. On any survey systems. “Centerline“ was held with Lighthouse on the shores of tion 2,900 feet away. As he Thus the survey system was jacks to compensate. A few given day, the lighthouse 0.01 ft for all seven rails. North Carolina’s barrier was usually working alone, to be used as a backup minutes later, the computer moved along this rail from Earl Dudley Associates gives islands near Buxton. robotics offered the only mechanism in case the readout suggested the light- 10 feet to 355 feet. special thanks to Greg viable, effective solution. engineering system failed. house was leaning a little Wagstaff and Mike Carlyle Cape Hatteras is the tallest New to the application of the During this transfer, the further to the left. Engineers In the meantime, while one from the Leica Product brick lighthouse in the world powerful technology, he surveyor used the TCA1103 compensated again. The robotic system continued to Support Group (Norcross, standing 208 feet tall and called on Earl Dudley to monitor the lighthouse surveyor using the robotic monitor the lighthouse GA) for their on-site help in weighing 4,800 tons. Over Associates to support the movement in two directions: system recorded data throughout the move, the evaluating the situation and the years, the sea eroded the on-site efforts. Earl Dudley the tilt and distance differen- reporting the exact opposite survey firm was also supporting this historic use surrounding sand and pres- Associates arrived with two tial. Operating in a stakeout conditions! required to monitor the of robotic technology. sed to within 160 feet of the of Leica’s TCA 1103 robotic mode, the robotic equip- elevation and alignment of Vicki Speed lighthouse foundation. The systems with coaxial Auto- ment continuously recorded the roll beams or the steel U.S. National Park Service matic Target Recognition. cut-fill quantities and 4 5.