Progress toward multi‐robot reconnaissance and the MAGIC 2010 competition

Abstract

Tasks like search‐and‐rescue and urban reconnaissance benefit from large numbers of robots working together, but high levels of autonomy are needed to reduce operator requirements to practical levels. Reducing the reliance of such systems on human operators presents a number of technical challenges, including automatic task allocation, global state and map estimation, robot perception, path planning, communications, and human‐robot interfaces. This paper describes our 14‐robot team, which won the MAGIC 2010 competition. It was designed to perform urban reconnaissance missions. In the paper, we describe a variety of autonomous systems that require minimal human effort to control a large number of autonomously exploring robots. Maintaining a consistent global map, which is essential for autonomous planning and for giving humans situational awareness, required the development of fast loop‐closing, map optimization, and communications algorithms. Key to our approach was a decoupled centralized planning architecture that allowed individual robots to execute tasks myopically, but whose behavior was coordinated centrally. We will describe technical contributions throughout our system that played a significant role in its performance. We will also present results from our system both from the competition and from subsequent quantitative evaluations, pointing out areas in which the system performed well and where interesting research problems remain. © 2012 Wiley Periodicals, Inc.

Evaluation of parallel reduction strategies for fusion of sensory information from a robot team

“…Prior work has looked at the impact of communication constraints between robot team members on the exploration strategy and efficiency. For teams where the primary sensor is laser, the communication bandwidth is not particular stressed and a common solution is just to compress the data [6]. However, when RGB-D sensors are used, such as the Kinect or, as in our case, stereo-cameras, the volume of data transmitted by even a small team can overwhelm the available bandwidth, even for the latest 802.11 standards.…”

“…However, as Olson et al [6] point out, communications and communication bandwidth become an issue for a large team of robots. For this reason, communication issues have also received some attention.…”

Robust loop closing over time for pose graph SLAM

“…In any case, neither approach can guarantee 100% accuracy. Olson et al [18] proposed a simple perloop verification method that uses a depth-limited search to identify loops and rejects loop closures that encode a transformation that varies significantly from identity. Traditionally, simple per-loop closure techniques measures the "loopiness" of the loop closure being proposed.…”

Deformable-medium affordances for interacting with multi-robot systems

“…Alternative approaches that have been proposed include induced flows across agents [4], boundary value control [5], or behavioral interactions [6], [7], [8]. A related question concerns the appropriate structure of user interfaces that ensures that sufficient situational awareness is provided and that the user is not overloaded with swarm-related inputs [9], [10].…”