At bauma, Bomag will be displaying for the first time its BW 177DH-3 roller with DGPS (Differential Global Positioning System). With the aid of satellite navigation, the position of the roller can be determined to the nearest 5 cm, the German firm says.

"The use of satellite navigation is a highly recommended particularly on large-scale construction projects; in other words in situations in which orientation depends very largely on the grid arrangement and advance planning of the sites as well as on the driver's reliability and ability to concentrate," observes a spokesman for Bomag. "And this is where the advantages of DGPS come into their own, both in construction operation and in quality assurance."

As a result of use of the system, high surface performance can be achieved, the roller trace can be followed precisely, which means extra help for the driver when moving along the roller paths, and the compacted areas can be documented precisely to the centimetre, co-ordinate related, and without any gaps in the record, he notes.

The global positioning system technology can be observed visually as well on the roller. A high-performance on-board PC, with colour touchscreen and specially developed software running under Windows NT, links the compaction-measured values with the path co-ordinates, stores them, and prints them out on easy-to-assess coloured cards.