8 research outputs found
Bounded Distributed Flocking Control of Nonholonomic Mobile Robots
There have been numerous studies on the problem of flocking control for
multiagent systems whose simplified models are presented in terms of point-mass
elements. Meanwhile, full dynamic models pose some challenging problems in
addressing the flocking control problem of mobile robots due to their
nonholonomic dynamic properties. Taking practical constraints into
consideration, we propose a novel approach to distributed flocking control of
nonholonomic mobile robots by bounded feedback. The flocking control objectives
consist of velocity consensus, collision avoidance, and cohesion maintenance
among mobile robots. A flocking control protocol which is based on the
information of neighbor mobile robots is constructed. The theoretical analysis
is conducted with the help of a Lyapunov-like function and graph theory.
Simulation results are shown to demonstrate the efficacy of the proposed
distributed flocking control scheme
Coordinated Control of UAVs for Human-Centered Active Sensing of Wildfires
Fighting wildfires is a precarious task, imperiling the lives of engaging
firefighters and those who reside in the fire's path. Firefighters need online
and dynamic observation of the firefront to anticipate a wildfire's unknown
characteristics, such as size, scale, and propagation velocity, and to plan
accordingly. In this paper, we propose a distributed control framework to
coordinate a team of unmanned aerial vehicles (UAVs) for a human-centered
active sensing of wildfires. We develop a dual-criterion objective function
based on Kalman uncertainty residual propagation and weighted multi-agent
consensus protocol, which enables the UAVs to actively infer the wildfire
dynamics and parameters, track and monitor the fire transition, and safely
manage human firefighters on the ground using acquired information. We evaluate
our approach relative to prior work, showing significant improvements by
reducing the environment's cumulative uncertainty residual by more than and times in firefront coverage performance to support human-robot
teaming for firefighting. We also demonstrate our method on physical robots in
a mock firefighting exercise
Unmanned Aerial Systems for Wildland and Forest Fires
Wildfires represent an important natural risk causing economic losses, human
death and important environmental damage. In recent years, we witness an
increase in fire intensity and frequency. Research has been conducted towards
the development of dedicated solutions for wildland and forest fire assistance
and fighting. Systems were proposed for the remote detection and tracking of
fires. These systems have shown improvements in the area of efficient data
collection and fire characterization within small scale environments. However,
wildfires cover large areas making some of the proposed ground-based systems
unsuitable for optimal coverage. To tackle this limitation, Unmanned Aerial
Systems (UAS) were proposed. UAS have proven to be useful due to their
maneuverability, allowing for the implementation of remote sensing, allocation
strategies and task planning. They can provide a low-cost alternative for the
prevention, detection and real-time support of firefighting. In this paper we
review previous work related to the use of UAS in wildfires. Onboard sensor
instruments, fire perception algorithms and coordination strategies are
considered. In addition, we present some of the recent frameworks proposing the
use of both aerial vehicles and Unmanned Ground Vehicles (UV) for a more
efficient wildland firefighting strategy at a larger scale.Comment: A recent published version of this paper is available at:
https://doi.org/10.3390/drones501001