Computer-Aided Visual Communication for Way-Finding in Emergency in Indoor Environment

Effective and rapid finding a way out in emergency is always a problem for occupants who get trapped in indoor environment such as inside buildings or vessels. In such a case, rescuers often rely on emergency signs or verbal communication to direct trapped people to the exits. However, many problems could arise on the move such as mobile signal interruption, low visible scene caused by dense smoke, etc. These problems might prevent the rescuers to communicate with Command Centre as well as to occlude them to see the emergency signs and passageway clearly. Additionally, a complex spatial layout with occluded spaces will add more difficulties in decision the correct way to take.

To address these problems, this paper introduces an approach which uses visual communication with the aid of Virtual Reality (VR) and Augmented Reality (AR) technology to provide rescuers the effective and efficient direction messages during rescue operation. Content of the visual support is determined and generated corresponding to the rescuer’s information (current position of rescuer, rescuer’s head orientation) and current environment visibility. It is made up by combining a dynamic You-Are-Here (YAH) map superimposing on either real environment or virtual environment. Dynamic YAH map which presents the comprehensive spatial layout will be rotated in a way that the map’s view is always congruent with the real layout with respect to the reader’s viewing perspective. In case of low visible scene, a virtual environment (VR mode) is retrieved to enable the rescuer to identify the current places and the escape routes. Alternatively, if scene is clear the user could be able to see the real scene (AR mode) while still keep track of superimposing information (computergenerated). The generated visual representation will be then displayed on rescuer’s Head Mounted Display (HMD) in realtime manner.

This kind of visual effect could reduce mental interpretation and the user’s manipulation in reading supporting information of an emergency task. Therefore, it could speed up the time for decision making in emergency situations or during rescue operation as well.