Soft Walls - Preventing Aircraft From Being Used as Weapons
:: In the wake of Sept 11, 2001, researchers in Electrical Engineering and Computer Sciences at UC Berkeley are studying ways to prevent aircraft from being used as weapons, with a project called Soft Walls. (From: The Scout Report)
In brief, modern aircraft all have electronics on board that is involved with the control and navigation of the aircraft. Many of the newer planes have computers on board that mediate the commands issued by the pilot and translate those commands into action, for example to bank and turn to the right. It is possible to modify the software in the computers in such a way that an airplane will refuse to enter pre-specified regions. We call these regions “no fly zones” and we call the boundaries of these regions “Soft Walls.” If an aircraft is equipped with the Soft Walls system, then if the pilot attempts to enter a no-fly zone, the airplane will be diverted. This happens gently at first, but if the pilot does not cooperate, then the system becomes more assertive. The key principle is to give the pilot as much control over the aircraft as is consistent with the constraint that the airplane does not enter the no-fly zone.The Soft Walls research study is part of The Ptolemy Project, which "studies modeling, simulation, and design of concurrent, real-time, embedded systems. The focus is on assembly of concurrent components."