Cooperative caging using autonomous aquatic surface vehicles

Abstract

Abstract-We present a study on the use of cooperative robots to execute a caging mission on the water's surface. In particular, we consider the problem of using two robotic boats (under-actuated autonomous surface vessels) connected with a floating rope, to 'capture' a floating object from a known location on the water's surface and 'shepherd' it to a designated position. This paper focuses on the cooperative control strategy of the two vessels. Each vessel's behavior is governed by a supervisor software module that handles the communication with the other vessel and controls all elementary tasks that compose the overall mission. The elementary tasks, specifically developed for under-actuated vessels, are arranged by priority, and merged using a behavior-based approach, namely the NullSpace based Behavioral control. The proposed technique is validated by field experiments with two autonomous robotic boats on the surface of a lake.

Cooperative caging and transport using autonomous aquatic surface vehicles

“…The numerical simulations and the experimental results validate the proposed strategy and represent the first realization of a capture and transport mission via caging in an aquatic setting. This paper extends the results reported in [13] that summarized preliminary work on the coordination control strategy for ASVs performing the caging mission. In this paper, Fig.…”

“…118 • 15 38.74 W) to validate the proposed strategy in the field. Preliminary experiments presented in[13] validate the coordination strategy,…”

“…1 Two autonomous surface vehicles cooperatively caging an object floating on a lake surface we present for the first time a complete caging experiment using a real floating rope; we also give a hydrodynamic analysis to estimate the forces applied by the floating rope to the ASV hull, and the consequent modifications made to the low-level control. In fact, in [13] the only coordination strategy was tested, the target was not really caged since we did not effectively use the floating rope in experiments and the hydrodynamic effects of the rope were neglected in the control. Moreover, as a matter of practicality, the experiments reported here employ a fault management strategy for the supervisor to manage the 'target missing' case.…”

Cooperative line of sight target tracking for heterogeneous unmanned marine vehicle teams: From theory to practice

“…Other interesting results can be found in [2], where several unmanned surface crafts followed a manned vehicle that was allowed to move randomly, keeping a close formation, like it is reasonable if the vehicles are intended to perform a common survey. In [3], a scenario is used in which two surface vehicles linked by a rope are intended to capture and to transport a floating target. All these applications differ considerably from the scenario that inspired our work.…”

Cooperative search with autonomous vehicles in a 3D aquatic testbed

“…Several platforms have been documented in ocean environments [4], [5], in rivers and lakes [6] and in indoor facilities such as swimming pools [7]. Additional examples use surface vehicles such as kayaks [8] or lowspeed air vehicles (e.g., balloons) as proxies for underwater vehicles [9]. Ocean-going vessels can be prohibitively expensive for the university researcher, costing from $500K to over a million dollars for a larger deep-sea vehicle, depending on the desired size, sensors, and depth capabilities.…”