Marinvent display wins U.S. patent

 - September 21, 2006, 6:10 AM

Marinvent, the Canadian research firm, received a U.S. patent last month for its dynamic non-linear display technology, developed to bring a semblance of calm to displays that simultaneously must provide high resolution and large value ranges.

While the technology could be applied to a variety of tasks, from readouts at nuclear power plants to the gauges on oil tankers, Marinvent president and founder John Maris developed the dynamic non-linear display concept specifically to aid pilots during aggressive flight maneuvers or after an upset.

Maris, a former Canadian Forces instructor pilot, explained that during recovery from an upset, the crew can become confused by the fast motion on altitude tapes, which in extreme situations can be barely readable. If the airspeed is increasing rapidly at the same time, the two tapes sliding in opposite directions can create an optical illusion. The result is the sensation that the aircraft is banking when in fact it is not.

The non-linear dynamic display shows minimum and maximum values in the far top and bottom range, and the current value (say, the present altitude) in a separate box at the center of the tape. If the values begin to change rapidly, the numbers in the box in the middle of the tape will move rapidly. The rest of the tape, however, will show a much slower, calmer movement, which Maris said lets the pilot better comprehend and assimilate precisely what is happening. The non-linear scaling on the vertical tape readout ensures that the critical value–zero feet altitude–always stays on the screen while maintaining excellent display resolution near the aircraft’s current altitude.

The new, non-linear display format could significantly improve flight safety because it increases pilot awareness of ground proximity, experts say.

“With a normal altitude indicator you don’t get a real feel for what’s going to happen in several minutes, because you don’t know where the ground is,” said Rob Erdos, a senior researcher at Canada’s National Research Council (NRC), which has evaluated the concept. “The benefit of this technology is that it puts the ground in view and lets you know how close you are to it, as well as how fast you’re approaching it. You get a better feel for what’s happening in terms of altitude.”

Flight trials of the technology were conducted last year at the NRC’s Institute for Aerospace Research.