@article {2022m-MohBicFraBarPra, title = {Aerial Tele-Manipulation with Passive Tool via Parallel Position/Force Control}, journal = {Applied Sciences, Special issue on Aerial Robotics for Inspection and Maintenance}, volume = {11}, year = {2021}, doi = {10.3390/app11198955}, author = {Mostafa Mohammadi and Davide Bicego and Antonio Franchi and Davide Barcelli and Domenico Prattichizzo} } @article {2018t-MasMohRobFra, title = {Shared Planning and Control for Mobile Robots with Integral Haptic Feedback}, journal = {The International Journal of Robotics Research}, volume = {37}, year = {2018}, month = {10/2018}, pages = {1395-1420}, abstract = {This paper presents a novel bilateral shared framework for online trajectory generation for mobile robots. The robot navigates along a dynamic path, represented as a B-spline, whose parameters are jointly controlled by a human supervisor and by an autonomous algorithm. The human steers the reference (ideal) path by acting on the path parameters which are also affected, at the same time, by the autonomous algorithm in order to ensure: i) collision avoidance, ii) path regularity and iii) proximity to some points of interest. These goals are achieved by combining a gradient descent-like control action with an automatic algorithm that re-initializes the traveled path (replanning) in cluttered environments in order to mitigate the effects of local minima. The control actions of both the human and the autonomous algorithm are fused via a filter that preserves a set of local geometrical properties of the path in order to ease the tracking task of the mobile robot. The bilateral component of the interaction is implemented via a force feedback that accounts for both human and autonomous control actions along the whole path, thus providing information about the mismatch between the reference and traveled path in an integral sense. The proposed framework is validated by means of realistic simulations and actual experiments deploying a quadrotor UAV supervised by a human operator acting via a force-feedback haptic interface. Finally, a user study is presented in order to validate the effectiveness of the proposed framework and the usefulness of the provided force cues.}, keywords = {Aerial Robotics, Optimal Trajectory Planning}, attachments = {https://homepages.laas.fr/afranchi/robotics/sites/default/files/2018t-MasMohRobFra-preprint.pdf , https://homepages.laas.fr/afranchi/robotics/sites/default/files/2018t-MasMohRobFra-video1.mp4 , https://homepages.laas.fr/afranchi/robotics/sites/default/files/2018t-MasMohRobFra-video2.mp4 , https://homepages.laas.fr/afranchi/robotics/sites/default/files/2018t-MasMohRobFra-video3.mp4}, author = {Carlo Masone and Mostafa Mohammadi and Paolo Robuffo Giordano and Antonio Franchi} } @article {2018u-StaMohBicDelYaPraRobLeeFra, title = {The Tele-MAGMaS: an Aerial-Ground Co-manipulator System}, journal = {IEEE Robotics and Automation Magazine}, volume = {25}, year = {2018}, month = {12/2018}, pages = {66-75}, attachments = {https://homepages.laas.fr/afranchi/robotics/sites/default/files/2018u-StaMohBicDelYaPraRobLeeFra-preprint.pdf , https://homepages.laas.fr/afranchi/robotics/sites/default/files/2018u-StaMohBicDelYaPraRobLeeFra.mp4}, author = {Nicolas Staub and Mostafa Mohammadi and Davide Bicego and Quentin Delamare and Hyunsoo Yang and Domenico Prattichizzo and Paolo Robuffo Giordano and Dongjun Lee and Antonio Franchi} } @conference {2017d-StaMohBicPraFra, title = {Towards Robotic MAGMaS: Multiple Aerial-Ground Manipulator Systems}, booktitle = {2017 IEEE Int. Conf. on Robotics and Automation}, year = {2017}, month = {05/2017}, pages = {1307-1312}, address = {Singapore}, abstract = {In this paper we lay the foundation of the first heterogeneous multi-robot system of the Multiple Aerial-Ground Manipulator System (MAGMaS) type. A MAGMaS consists of a ground manipulator and a team of aerial robots equipped with a simple gripper manipulator the same object. The idea is to benefit from the advantages of both kinds of platforms, i.e., physical strength versus large workspace. The dynamic model of such robotic systems is derived, and R Ro its characteristic structure exhibited. Based on the dynamical i structure of the system a nonlinear control scheme, augmented with a disturbance observer is proposed to perform trajectory tracking tasks in presence of model inaccuracies and external disturbances. The system redundancy is exploited by solving an optimal force/torque allocation problem that takes into account the heterogeneous system constraints and maximizes the force manipulability ellipsoid. Simulation results validated the proposed control scheme for this novel heterogeneous robotic system. We finally present a prototypical mechanical design and preliminary experimental evaluation of a MAGMaS composed by a kuka LWR4 and quadrotor based aerial robot.}, attachments = {https://homepages.laas.fr/afranchi/robotics/sites/default/files/2017d-StaMohBicPraFra-preprint.pdf , https://homepages.laas.fr/afranchi/robotics/sites/default/files/2017d-StaMohBicPraFra.mp4}, author = {Nicolas Staub and Mostafa Mohammadi and Davide Bicego and Domenico Prattichizzo and Antonio Franchi} } @conference {2016n-MohFraBarPra, title = {Cooperative Aerial Tele-Manipulation with Haptic Feedback}, booktitle = {2016 IEEE/RSJ Int. Conf. on Intelligent Robots and System}, year = {2016}, month = {10/2016}, pages = {5092-5098}, address = {Daejeon, South Korea}, abstract = {In this paper, we propose a bilateral tele-operation scheme for cooperative aerial manipulation in which a human operator drives a team of Vertical Take-Off and Landing (VTOL) aerial vehicles, that grasped an object beforehand, and receives a force feedback depending on the states of the system. For application scenarios in which dexterous manipulation by each robot is not necessary, we propose using a rigid tool attached to the vehicle through a passive spherical joint, equipped with a simple adhesive mechanism at the tool-tip that can stick to the grasped object. Having more than two robots, we use the extra degrees of freedom to find the optimal force allocation in term of minimum power and forces smoothness. The human operator commands a desired trajectory for the robot team through a haptic interface to a pose controller, and the output of the pose controller along with system constraints, e.g., VTOL limited forces and contact maintenance, defines the feasible set of forces. Then, an on-line optimization allocates forces by minimizing a cost function of forces and their variation. Finally, propeller thrusts are computed by a dedicated attitude and thrust controller in a decentralized fashion. Human/Hardware in the loop simulation study shows efficiency of the proposed scheme, and the importance of haptic feedback to achieve a better performance.}, attachments = {https://homepages.laas.fr/afranchi/robotics/sites/default/files/2016n-MohFraBarPra-preprint.pdf , https://homepages.laas.fr/afranchi/robotics/sites/default/files/2016n-MohFraBarPra.mp4}, author = {Mostafa Mohammadi and Antonio Franchi and Davide Barcelli and Domenico Prattichizzo} } @conference {2015c-GioMohFraPra, title = {A Force-based Bilateral Teleoperation Framework for Aerial Robots in Contact with the Environment}, booktitle = {2015 IEEE Int. Conf. on Robotics and Automation}, year = {2015}, month = {05/2015}, pages = {318-324}, address = {Seattle, WA}, keywords = {Aerial Physical Interaction, Aerial Robotics, Bilateral Shared Control of Mobile Robots}, attachments = {https://homepages.laas.fr/afranchi/robotics/sites/default/files/2015c-GioMohFraPra-preprint.pdf , https://homepages.laas.fr/afranchi/robotics/sites/default/files/2015c-GioMohFraPra.mp4}, author = {Guido Gioioso and Mostafa Mohammadi and Antonio Franchi and Domenico Prattichizzo} }