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This paper considers dynamic coverage control of multiple power-constrained agents subject to 3D rigid body kinematics. The agents are deployed to patrol a domain until the entire space has reached a satisfactory level of coverage. This is achieved through the gathering of information by a forward-facing sensor footprint, modelled as an anisotropic spherical sector. Coverage and collision avoidance guarantees are met by a hybrid controller consisting of four operating modes: local coverage, global coverage, waypoint scan and subdomain transfer. Energy-aware methods are encoded into the global coverage state to shift the bulk of spatial redistribution onto less constrained agents. Additionally, a novel domain partitioning strategy is used that directs individual agents to explore within concentric hemispherical shells around a centralized charging station. This results in flight paths that are guaranteed to terminate at the charging station in the limit that agent batteries expire. The efficacy of this algorithm is presented through experimental trials with three agents in an indoor environment. Simulations are provided for ten agents.

This paper considers the persistent coverage of a 2-D manifold that has been embedded in 3-D space. The manifold is subject to continual impact by intruders which travel at constant velocities along arbitrarily oriented straight-line trajectories. The trajectories of intruders are estimated online with an extended Kalman filter and their predicted impact points contribute normally distributed decay terms to the coverage level. A formal hybrid control strategy is presented that allows for power-constrained 3-D free-flyer agents to persistently monitor the domain, track and intercept intruders, and periodically deploy from and return to a single charging station on the manifold. Guarantees on intruder interception with respect to agent power lifespans are formally proven. The efficacy of the algorithm is demonstrated through simulation., Extended version of work conditionally accepted for publication in Automatica

This paper considers the persistent coverage of a 2-D manifold that has been embedded in 3-D space. The manifold is subject to continual collisions by intruders that are generated with random trajectories. The trajectories of intruders are estimated online with an extended Kalman filter and their predicted impact points contribute normally distributed decay terms to the coverage map. A formal hybrid control strategy is presented that allows for power-constrained 3-D free-flyer agents to persistently monitor the domain, track and intercept intruders, and periodically deploy from and return to a single charging station on the manifold. Guarantees on intruder interception with respect to agent power lifespans are formally proven. The efficacy of the algorithm is demonstrated through simulation.

This paper considers dynamic coverage control of multiple power-constrained UAVs. The UAVs are deployed to patrol a domain until the entire space has reached a satisfactory level of coverage. This is achieved through the gathering of visual information by a forward-facing camera, modeled as an anisotropic spherical sector. Coverage and collision avoidance guarantees are met through the design of a high-level kinematic hybrid control scheme consisting of a hold state as well as three coverage modes: local, global and scan mode. Energy-aware methods are encoded into the global coverage state to shift the bulk of spatial redistribution onto less constrained agents. The efficacy of this algorithm is presented through simulation.

This paper considers dynamic coverage control of unicycle multi-agent systems under power constraints. The agents under consideration implement a visually based patrol protocol. They observe their environment via forward-facing conical anisotropic sensing regions. A local coverage control strategy is presented that allows for the cooperative search of a domain while maintaining collision avoidance guarantees using a novel control method based on the coverage level. Additionally, a novel energy-aware global coverage technique is introduced that restricts the operating range of power-constrained agents while shifting the network redistribution effort onto less constrained agents. The results of several scenarios are presented in simulation to illustrate the efficacy of these algorithms.

Solitary extramedullary plasmacytomas are uncommon neoplasms. They occur most frequently in the upper aerodigestive tract and account for 4% of the nonepithelial tumors in this site. The evolution of a plasmacytoma is unsteady and symptoms at presentation have included dystonia, dysphagia, oral pain, cough, and dyspnea on exertion. Plasmacytoma of the upper aerodigestive tract has not been previously reported as a cause of obstructive sleep apnea.