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This paper presents a direct image-based controller to perform the guidance of a mobile manipulator using image-based control. An eye-in-hand camera is employed to perform the guidance of a mobile differential platform with a seven degrees-of-freedom robot arm. The presented approach is based on an optimal control framework and it is employed to control mobile manipulators during the tracking of image trajectories taking into account robot dynamics. The direct approach allows us to take both the manipulator and base dynamics into account. The proposed image-based controllers consider the optimization of the motor signals sent to the mobile manipulator during the tracking of image trajectories by minimizing the control force and torque. As the results show, the proposed direct visual servoing system uses the eye-in-hand camera images for concurrently controlling both the base platform and robot arm. The use of the optimal framework allows us to derive different visual controllers with different dynamical behaviors during the tracking of image trajectories. This research was supported by the Valencia Regional Government through project GV/2018/050.

[Resumen] Este artículo propone un sistema de control visual directo basado en imagen para guiar a un manipulador móvil. El robot está compuesto por una plataforma móvil diferencial con un brazo de 7 gdl (grados de libertad) y una cámara en configuración eye-in-hand. Como se describe en el documento, la información visual se emplea para guiar tanto el robot manipulador como la plataforma base durante el seguimiento de trayectorias definidas en el plano imagen. A diferencia de los enfoques anteriores, el sistema propuesto en este documento emplea un control visual directo para guiar al manipulador móvil. De esta forma, el controlador genera directamente los pares (fuerza y momentos) que se aplicarán al manipulador y la plataforma base teniendo en cuenta la dinámica del robot. Este artículo describe los diferentes componentes cinemáticos y dinámicos del controlador propuesto y se valida a partir del seguimiento de trayectorias de imágenes repetitivas y no repetitivas. [Abstract] This paper proposes a direct image-based visual servoing system for the guidance of a mobile manipulator. The robot is composed of a mobile differential platform with a 7 dof (degrees of freedom) arm and an eye-in-hand camera. As described throughout the paper, the visual information is employed to guide both the robot manipulator and the base platform for the tracking of image trajectories. In contrast with previous approaches, the one proposed in this paper employs a direct visual servoing system for guiding mobile manipulators. In this case, the controller directly generates the torques (force and moments) to be applied to the manipulator and base platform taking into account the robot dynamics. This paper describes the different kinematic and dynamic components of the proposed controller and it is validated during the tracking of repetitive and nonrepetitive image trajectories