José Guadalupe Romero

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— Regulation of passive outputs of nonlinear systems can be easily achieved with an integral control (IC). In many applications, however, the signal of interest is not a passive output and ensuring its regulation remains an open problem. Also, IC of passive systems rejects constant input disturbances, but no similar property can be ensured if the(More)
— The problem of robustness improvement, visà vis external disturbances, of energy shaping controllers for mechanical systems is addressed in this paper. First, it is shown that—if the inertia matrix is constant—constant disturbances (both, matched and unmatched) can be rejected simply adding a suitable integral action. For systems with non–constant inertia(More)
Despite the recent progress in physically interactive and surgical robotics, the active deformation of compliant objects remains an open problem. The main obstacle to its implementation comes from the difficulty to identify or estimate the object's deformation model. In this paper, we propose a novel vision-based deformation controller for robot(More)
Despite the recent progress in physically interactive and surgical robotics, the active deformation of compliant objects remains an open problem. The main obstacle comes from the difficulty to identify/estimate the object's deformation properties. This paper presents a new visually servoed deformation controller for unknown elastic objects. The control law(More)
— A solution to the problem of global exponential tracking of mechanical systems without velocity measurements is given in the paper. The proposed controller is obtained combining a recently reported exponentially stable immersion and invariance observer and a suitably designed state–feedback passivity–based controller, which assigns to the closed–loop a(More)
In this paper, we address the active deformation control of compliant objects by robot manipulators. The control of deformations is needed to automate several important tasks, for example, the manipulation of soft tissues, shaping of food materials, or needle insertion. Note that in many of these applications, the object's deformation properties are not(More)
— In this paper, we address the global exponential stability problem of perturbed mechanical systems in free-motion and interacting with passive environments. Particularly, we are interested in incorporating an exponentially stable response to a robust passivity-based control design. We formulate and analyse the stability of the proposed controllers based(More)
— In this brief, we address the robust force regulation problem of mechanical systems in physical interaction with compliant environments. The control method that we present is entirely derived under the energy shaping framework. Note that for compliant interactions, standard energy shaping methods (i.e., potential shaping controls using static-state(More)