Jnaneshwar Das

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This paper presents an oceanographic toolchain that can be used to generate multi-vehicle robotic surveys for large-scale dynamic features in the coastal ocean. Our science application targets Harmful Algal Blooms (HABs) which have significant societal impact to coastal communities yet are poorly understood ecologically. Bloom patches can be large spatially(More)
Robotic sampling is attractive in many field robotics applications that require persistent collection of physical samples for ex-situ analysis. Examples abound in the earth sciences in studies involving the collection of rock, soil, and water samples for laboratory analysis. In our test domain, marine ecosystem monitoring, detailed understanding of plankton(More)
Dynamic positioning is an important application for marine vehicles that do not have the luxury of anchoring or mooring themselves. Such vehicles are usually large and have arrays of thrusters that allow for controllability in the sway as well as the surge and yaw axes. Most smaller boats however, are underactuated and do not possess control in the sway(More)
— We present a collaborative team of two under-actuated autonomous surface vessels (ASVs) that performs a cooperative navigation task while satisfying a communication constraint. Our approach is based on the use of a hierarchical control structure where a supervisory module commands each vessel to perform prioritized elementary tasks, a behavior-based(More)
Autonomous Underwater Vehicles (AUVs) are revolutionizing oceanography through their versatility, autonomy and endurance. However, they are still an underutilized technology. For coastal operations, the ability to track a certain feature is of interest to ocean scientists. Adaptive and predictive path planning requires frequent communication with(More)
Addressing the challenges of feeding the burgeoning world population with limited resources requires innovation in sustainable, efficient farming. The practice of precision agriculture offers many benefits towards addressing these challenges, such as improved yield and efficient use of such resources as water, fertilizer and pesticides. We describe the(More)
— We address the effects of the aquatic communication channel constraints on the control performances of marine robot teams. The aquatic acoustic channels suffer from significant frequency and distance dependent attenuation, extensive time-varying multipath, motion-induced Doppler distortion and extreme channel latency due to the low speed of sound.(More)
With the advent of Autonomous Underwater Vehicles (AUVs) and other mobile platforms, marine robotics have had substantial impact on the oceanographic sciences. These systems have allowed scientists to collect data over temporal and spatial scales that would be logistically impossible or prohibitively expensive using traditional ship-based measurement(More)