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Localization is a key ability for robot navigation and collision avoidance. The advent of technologies such as GPS have led to many improvements in terrestrial navigation. Unfortunately traditional electromagnetic (EM) communications propagate poorly through lossy media such as underwater and underground. Therefore, localization remains a challenging problem in such environments, necessitating other approaches such as acoustics and magnetic induction (MI). This paper investigates estimating the relative location of a pair of MI triaxial coil antennas in air, as a preliminary step to underwater applications. By measuring the voltages induced in the receiving antenna when the transmitting antenna's coils are turned on sequentially, the distance between the antennas can be computed. Then, with knowledge of the current velocities of the antennas, we can apply a particle filter to generate an estimate of the location of the transmitting antenna with respect to the receiving one. The theory is supported by simulations and later verified through a series of experiments. 

This paper investigates motion planning for one or more robot(s) that attempt to harvest agents from a moving swarm. Generating motion paths that maximize the number of agents harvested differs from many traditional coverage problems because the agents move. This movement allows previously cleared areas to become recontaminated. We assume that the swarm agents prefer certain regions over others, and that we can represent the swarm by a Markov Process that encodes the agents' preferred regions and their speed of motion. We exploit this model to design and simulate robotic coverage paths that maximize the number of agents harvested by a fleet of robots in a given time budget. 

Magnetic Induction (MI) is a promising technique for near-field wireless underwater communications. Although the literature has some theoretical analyses and lab experiments for underwater MI communication, there is a lack of field tests in underwater environments, especially in subsea environments. In this paper, we leverage the remotely operated vehicle (ROV) and the remotely controlled boat (RCB) to develop an MI wireless communication system, and conduct field tests for MI communication performance in both fresh water and sea water. The experiment results show that even in the most challenging subsea environment, the MI communication has very good near-field transmission performance with a small coil antenna and low power consumption.