If Captain Kirk were an equipment operator, this would be his chair. On the right, a single joystick steers. To the left, a color computer screen shows travel direction and speed. The one-piece console rotates automatically as the operator moves the machine from forward to reverse. All that’s missing is sound advice from Mr. Spock.

In Control Paving operators don’t have to twist their necks, thanks to a new cab design.(Photo by Tudor Hampton
for ENR)

Mounted independently of the frame, a climate-controlled cab slides 12-in. side-to-side for visibility. Underneath, two access doors swing open and a hydraulic hand pump slowly drops the engine block to the ground for service.

These high-tech features are offered on three new models of rigid-frame asphalt rollers from Germany’s Hamm AG, a unit of the Wirtgen Group, a $914-million-a-year manufacturer of paving, milling and rolling equipment. First introduced in Europe a year ago and shown last month at CONEXPO-CON/AGG, the 4-to-9-tonne compaction machines will be available to North American buyers early next year, according to company officials.

Gottfried Beer, product manager, calls the DV series "a new step" in the development of asphalt rollers. The units incorporate tandem vibratory and oscillating drums, a Hamm exclusive that keeps one drum on the ground at all times. Stuart W. Murray, president of Wirtgen America Inc., Nashville, Tenn., says that vibratory drums spend "half their life" off the ground. Oscillating drums maintain contact, yielding smooth and dense pavement, he adds.

Five years of research and development on the DV culminated with Hamm’s new "HI-DRIVE" operator station. Because the captain’s chair rotates 360° as the operator guides the machine, the joystick always points in the direction of travel, enhancing operator comfort.

But the HI-DRIVE cab design did not come without some trademark-infringement hurdles. The "smart" joystick triggered one auto maker to "put their nose under our tent," Murray says, although no formal complaints were ever filed. Hamm eventually received two major European design awards for the DV compaction machines. Several patents are still pending.

Wirtgen has not yet set a price for the DV series in North America. But as far as sales go, it expects to ship over 50 to 75 units next year. So far, it already has sold about 60 in Europe.