Rapid exploration of unknown areas through dynamic deployment of mobile and stationary sensor nodes

Abstract

When an emergency occurs within a building, it may be initially safer to send autonomous mobile nodes, instead of human responders, to explore the area and identify hazards and victims. Exploring all the area in the minimum amount of time and reporting back interesting findings to the human personnel outside the building is an essential part of rescue operations. Our assumptions are that the area map is unknown, there is no existing network infrastructure, long-range wireless communication is unreliable and nodes are not locationaware. We take into account these limitations, and propose an architecture consisting of both mobile nodes (robots, called agents) and stationary nodes (inexpensive smart devices, called tags). As agents enter the emergency area, they sprinkle tags within the space to label the environment with states. By reading and updating the state of the local tags, agents are able to coordinate indirectly with each other, without relying on direct agent-to-agent communication. In addition, tags wirelessly exchange local information with nearby tags to further assist agents in their exploration task. Our simulation results show that the proposed algorithm, which exploits both tag-to-tag and agent-to-tag communication, outperforms previous algorithms that rely only on agent-to-tag communication.

A Concept of Layered Robust Communication between Robots in Multi-agent Search & Rescue Scenarios

“…Taking the MAF algorithm as the base for implementation of the concept again will show that without direct communication only a small amount of data communicated between two agents, which is sufficient for the base algorithm as the work of Ferranti et al in [19], [16] and our work in [20] has shown. As mentioned in the introduction additional data can contain SLAM generated maps of the environment by the different robots.…”

“…The main drawback of this approach is that the agents may not find the markings again. To combat this problem the use of passive or active Radio-frequency identification (RFID) chips was proposed and tested in [13], [14], [15], [16].…”

“…Baglietto et al [15] and Ferranti et al [16] used these ideas to create multi-agent algorithms already using these mechanisms to allow an indirect communication via the distributed tags.…”

“…Examples of these algorithms are the Brick & Mortar algorithm, the extended variant from the same authors HybridExploration, and the Multi-Agent Flood algorithm (respectively [19], [16], [20]). …”

Exploiting a meeting channel to interconnect mobile robots

“…Such mobile robots can also be used to collaborate with each other to detect events or track mobile targets (Hogg et al, 2002;Lambrou and Panayiotou, 2009;Mottaghi and Vaughan, 2007). Another example is search and rescue operations, where robots are used to locate survivors in environments that might be difficult to access (such as partially collapsed buildings) or too large to explore quickly by first responders (Ferranti et al, 2009).…”