A lesson in engineering economics

Prior to the making of Titanic, the largest single load ever moved on a movie set was in Batman and Robin, released in mid-1997. For key scenes in the movie, engineers needed to develop a power system to move and rotate a 45 ft-long telescope (Design News, 7-21-97). The telescope weighed 95,000 lbs.

So how did engineers feel when initially confronted with the task of lifting a two-million-pound scale model of the Titanic? In a word, skeptical. "It was the biggest load I'd ever been asked to move during 18 years in this business," notes John Rothas of Mayo Hydraulics, Bakersfield, CA.

After scribbling out some calculations, however, they soon learned that they could move it at rates of up to six inches per second--a significant speed for a two million-lb load. Using an eight-axis motion controller, they also synchronized movement of eight hydraulic actuators to within ±1.0 inches of the commanded position. The hydraulic portion of the project cost approximately $1.2 million.

"At first I thought it couldn't be done," recalls Greg Paddock, hydraulic territory manager for Parker Hannifin's Motion and Control Group, Irvine, CA. "But the lesson is that with enough money and enough time, just about anything can be done."