Modeling and control for underwater robotic manipulators - an example

A closed form dynamic model of an autonomous underwater robotic vehicle (URV) with multiple manipulators is derived in this paper. The model components include the vehicle body, the m manipulators with n_i links for each manipulator. It is a generic model that can cope with any number of manipulators and links. The four major hydrodynamic forces included in this model are: added mass, profile drag, fluid acceleration and buoyancy. The model for an URV with two manipulators attached to it is used as an example to show the performance of the model based control scheme. Tracking motions for both vehicle and the two manipulators are tested to show the effectiveness of the nonlinear feedback control scheme. It successfully decouples and linearizes the complex URV system with manipulators, thus attaining a good coordinated control between the vehicle and the attached manipulators