Maintaining network connectivity and performance in robot teams

Abstract

In this paper, we present an experimental study of strategies for maintaining end-to-end communication links for tasks such as surveillance, reconnaissance, and target search and identification, where team connectivity is required for situational awareness. Our main contributions are threefold: ͑a͒ We present the construction of a radio signal strength map that can be used to plan multi-robot tasks, and also serve as useful perceptual information. We show how a nominal model of an urban environment obtained by aerial surveillance, is used to generate strategies for exploration. ͑b͒ We present reactive controllers for communication link maintenance; and ͑c͒ we consider the differences between monitoring signal strength versus data throughput. Experimental results, obtained using our multi-robot testbed in three representative urban environments are presented with each of our main contributions.

Autonomous transportation and deployment with aerial robots for search and rescue missions

“…In EMBER, range information is used for searching and tracking of mobile targets, using multiple robots (Hollinger et al, 2009). The multi-agent (combined ground and air) tasking also have been demonstrated recently (Hsieh et al, 2007;Hsieh et al, 2008).…”

Moving as a whole: multirobot traveling problem constrained by connectivity

“…However, this strategy cannot guarantee global connectivity when one set of robots loses connection with another set simultaneously. Hsieh et al [4] implemented a neighbor-based method where robots stayed connected to certain neighbors. If the link quality among the robots fell below a certain threshold, they moved to these neighbors.…”

“…CNN is lightweight and robust to environmental dynamics, while B-LKH generates solutions with less TTD as the cost of higher computational complexity. (4) Simulations are designed to investigate the influence of the amount of robots and ISs, communication range, and IS distributions. Comparisons of the algorithms are also made.…”

Coordinated Trajectory Planning for Efficient Communication Relay Using Multiple UAVs

“…An airborne relay can effectively connect to units operating over the horizon, beyond normal communication range, or under limited satellite communication environments. However, even if the equipment development is relatively mature, and considerable research on a mobile ad-hoc networking has been performed for ground robot teams [4,5,6], where to locate UAVs for efficient relay is still a pending problem due to UAV's dynamic and operational constraints.…”