AUGUST 2016 CREW SAFETY. Product Review Leica Zeno 20. The Humble Rebar World-changing invention. GIS & Surveyors Long and winding road

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1 AUGUST 2016 CREW SAFETY Product Review Leica Zeno 20 GIS & Surveyors Long and winding road The Humble Rebar World-changing invention

2 Gaesing teaches a group of students from Esteli s university.

3 A Caffeinated Pick-Me-Up for a Surveying Career Ulrich Gaesing has been a surveying manager for Bielefeld, Germany, for 40 years. So when he was asked to help a coffee-growers cooperative in Nicaragua, Gaesing jumped at the opportunity. In early 2015 he embarked on a six-week project to survey small-scale coffee plantations in Central America s cloud forest. Nestled in the northern highlands of Nicaragua, Esteli is the country s third largest city; mountains surrounding Esteli reach 1,600 m (5,250 ft) above sea level and are forested in native and exotic trees. Beneath their shade, coffee plants thrive in the region s rich volcanic soil. Despite the region s ideal conditions, Esteli s small-scale coffee farmers remain poor; in order to command higher prices for their Arabica coffee beans, many apply for organic certification. The certification process requires them to submit maps showing clear farm boundaries; however, surveying costs to obtain these maps are typically out of reach. That s why in 2014 the Union of Cooperatives of Agriculture (UCA) contacted Esteli s sister city, Bielefeld, Germany, for help. Time to Change Things Up In 2014 Ulrich Gaesing, the longtime surveying manager for Bielefeld City, was ready for a change. Ulrich had visited Esteli earlier; in 1993 he was sent by Bielefeld to create a topical land register for the Central American city. I felt returning to Nicaragua would be a great adventure and give me the chance to do some good in the world, Gaesing said. This time he would be travelling independently with the support of his employer, but using vacation time and paying for his own flights. At the 2014 Trimble Dimensions User Conference, Gaesing met contacts including one from ALLTERRA, a geospatial distributor in Germany who generously provided equipment to the expedition: a Geodimeter 608S Autolock Total Station and two Trimble GeoXH GPS handhelds, as well as supporting software. While in Bielefeld Gaesing uses the Trimble S6 Total Station and a Trimble R10 GNSS System, in Nicaragua he used the Geodimeter Total Station under the thick tree canopy.» VIVIENNE WALLACE

4 L-R: Yoarci González, Ulrich Gaesing, Ramón Garcia and Julio Zeledón. Photo taken by the group s interpreter, Manuel Jung. A New Daily Grind From February to March 2015, Gaesing stayed in Esteli city on weekends; Monday through Friday he lived in the mountains with the coffee growers. I lived their life, he said. We rose with the sun at 5:30 a.m. and started the day with corn tortillas and coffee. Gaesing worked in a team of four or five that included a German-born translator, a Nicaraguan worker from the UCA and one or two local students. Because Esteli coffee trees grow among other larger trees, farm boundaries are not obvious. So on first arriving at each The simple accommodation Gaesing shared with the farmers was comfortable, but provided little insulation from cold mountain air at nighttime. farm, Gaesing walked the boundaries with the grower. He would then negotiate the forest canopy to capture his first GPS points. Imagine surveying in a country where there are no surveying points and no GPS reference system. That s what Nicaragua is like, said Gaesing. Knowing this constraint, Ulrich originally planned to use one GPS handheld on a surveying point with known UTM coordinates and use the second handheld for a new point perhaps 30 km (19 mi) away. He would then use simple differential calculations to compute coordinates for the new point. Unfortunately, no known surveying points were available, even in Esteli. Because he needed reference points to create a cadaster, Ulrich simply collected a few GPS positions a minimum of two per coffee plot. Thereafter he relied on terrestrial surveying with the Geodimeter. In the circumstances, the autonomous 5-m (16-ft) accuracy of the handhelds was sufficient. I was so pleased to receive the Geodimeter, said Gaesing. I used a newer Trimble CU control unit I was familiar with, and the instrument performed very well. Because there was no electricity in the mountains I used solar panels to recharge the batteries. Unfortunately, the only tripod I could source in Esteli had just two good legs! Conditions in the mountains were pleasant during the day, but at 1,200 m (3,900 ft) the temperatures plummeted at night, and

5 At home, Gaesing uses the Trimble S6 Total Station and Trimble R10 GNSS System. In Nicaragua, Ulrich stepped back in time, putting a Geodimeter Total Station through its paces under the tree canopy. the farmhouses had no electricity, phone or Internet. In the evenings, Gaesing recorded his experiences in a journal by torchlight. I wrote down all of my impressions and everything I saw, he said. I knew I wanted to share my story in some way or other when I returned home. When he finished work at each farm, Gaesing carried all his gear on foot to the next location. Postprocessing would wait till the weekend in Esteli when he had access to electricity and the Internet; Gaesing could then import data into Trimble Survey Manager software and roughly check his GPS coordinates in Google Earth. He ed his data to colleagues in Germany, who generated final maps via Trimble s GEOgraf software and AutoCAD How to Leave a Lasting Legacy Gaesing didn t just provide Esteli with farm surveys; he taught local Esteli students how to survey. For me the most important thing was to survey as much as possible during my time, he said. The second-most important thing was to teach other people. Gaesing was assisted each week by different students from Esteli s public university, Universidad Nacional de Ingenieria (UNI). One weekend, Gaesing taught a surveying class of keen students about GPS basics, coordinate systems and how to use the Geodimeter. Gaesing paid it forward by leaving the Geodimeter and Trimble GeoXH instruments with the university. A Mutually Beneficial Experience During his stay, Gaesing surveyed 8 farms totaling 35 hectares (86 acres) of coffee plots; each of the farms received organic certification. While the legacy he left in Esteli was unquestionably significant and successful, his own experiences in Esteli in 1993 and 2015 also left a great impression on him. And the thanks he received from the UCA gave him enormous satisfaction. Much like a good strong cup of organic mountain-grown coffee. Vivienne Wallace is a freelance writer specializing in high-tech positioning solutions, including conventional, GNSS and spatial imaging survey systems. Vivienne is based in New Zealand. Gaesing has turned his journal entries, memories and anecdotes, and photos of each visit into a book, recently published in Germany.