Evaluating the Optimal Heat Detector Deployment for Fire Detection

Wireless Sensor Networks (WSNs), composed of spatially distributed autonomous sensor nodes, have a wide range of application. One of the most interesting phenomena that can be monitored by WSN, among various physical, chemical and biological phenomena and different kind of events, is fire. In case of fire presence continuous monitoring and/or recording of sensitive or restricted parts are necessary for timely response and reaction. Fire monitoring applications require accurate deployment of the sensor nodes because their positions have a dramatic impact on the effectiveness of the WSN and the efficiency of its operation. The choice of the deployment scheme depends highly on the type of sensors, application and the environment that the sensors will operate in (residential buildings, hospitals, historical buildings, malls etc.). The main advantage of WSN usage can be also identified as a simple reconfiguration and maintenance of the created infrastructure, what can be of great importance for systems that are physically unaffected by changes, but they tend to change in terms of safety (e.g. ships, oil productive platforms, etc.). Knowing that the positions of nodes have a dramatic impact on the effectiveness of the WSN and the efficiency of its operation, in this paper the various strategies for positioning nodes in WSNs are considered: grid, triangular and strip. The objective of this paper is to properly place the heat detectors in certain indoor area, in such way that next two important network design objectives are satisfied: to maximize the network lifetime after fire ignition and to use a minimum number of sensors in order to achieve full area coverage.