Optimal Positioning of Mobile Manipulators Using Closed Form Inverse Kinematics

Mobile manipulators have recently been subject to studies and researches thanks to their augmented mobility and interaction capability. In the precision agriculture field, the development and implementation of such systems can be advantageous in every aspect of the farm activities, e.g. harvesting, pruning, or trimming. This paper presents the implementation of a 7 degree of freedom manipulator upon a mobile rover prototype, designed for precision agriculture, in order to perform grape sampling tasks. While the redundancy of the arm is used to perform off-line collision avoidance with the environment and the mobile base itself, thanks to sampling based path planning methods, a closed form inverse kinematics solution allows to select the posture which maximizes the manipulability index of the manipulator. To do so, base mobility is used to reach the target and properly position the arm. The overall architecture was implemented on the real system and successfully validated through experimental tests.