Under a situation where network infrastructures are interrupted by a devastating natural disaster, few communication channels left for survivors to request help are proximity-based communications on their mobile devices, for example Bluetooth and Wi-Fi direct. Since these technologies have a limited transmission range, rescue teams need to travel over a disaster area and physically come close to survivors to detect signals emitted from their devices. In this paper we demonstrate how to combine connectionless broadcast capabilities of existing mobile/wearable devices on the market, together with the high-mobility and proximity-based connectivity of drones (e.g., quadcopters), to help rescue teams discover signals from survivors.
Followings are the Android APK binaries for each component.
|Component||Device type||APK file|
The figure illustrates the entire system of the proposed survivor locator system. This system is decentralized and consists of 3 components: Broadcaster, Locator, and Aggregator. These components communicate with each other using proximity-based wireless channels based on Wi-Fi and Bluetooth.
The Broadcaster is intended for survivors who request help. This component runs on privately owned smart-devices such as smartphones or smartwatches. It broadcasts emergency messages required to locate survivors by using connectionless broadcast. An emergency message contains at least the identifier of survivor's device and GPS coordinates, if available.
The Locator detects messages emitted from Broadcasters, and is supposed to run on moving drones (or any other moving device). When a Locator device detects a message transmitted from a Broadcaster device, it stores such information into its local storage. If the received message does not contain valid GPS coordinates (which may be common indoor), they are replaced with the coordinates of the Locator drone itself. If a locator comes in proximity with another locator, they will exchange information about detected broadcasters.
The Aggregator runs on devices/computers used by rescue teams in a control center. Locator drones fly back to the control center, uploading collected emergency messages to the Aggregator. The Aggregator visualizes the location of each survivor based on the received messages on a map. By analyzing the visualized results and considering resources/time available, rescue teams can then build an efficient rescue plan in a timely manner.