Browsing by Keyword "Visual servoing"
Now showing 1 - 2 of 2
Results Per Page
Sort Options
Item Design of a microgripping system with visual and force feedback for MEMS applications(2006) Giouroudi, I.; Hotzendorfer, H.; Andrijasevic, D.; Ferros, M.; Brenner, W.; COMPOSITEThis paper reports the design of a microgripping system with visual and force feedback for handling and assembly in microtechnology. The system consists of a microgripper, an electromagnetic microactuator, the Kleindiek Micromanipulator MM3A, a light microscope, a CCD camera and a computer. The microgripper is mounted on the Kleindiek Micromanipulator MM3A which has 3 degrees of freedom (two rotational axes, one linear axis), wide working range (240° in the rotational axes, 12 mm in the linear axis) and subnanometer resolution. An external CCD camera provides images for obtaining the actual axis positions and by applying inverse kinematics the actual position of the manipulators end-effector is calculated so as to perform coarse positioning. A second CCD camera in combination with a light microscope provides sufficiently precise data to perform the actual manipulation tasks. Since the gripper is electromagnetically driven, the movement of the gripper tips is a continuous mapping of the applied current. The applied current can be correlated to the actual distance between the tips by calibration. In case of gripping an object, the tips are hindered to close to the full extent. The resulting gripping force depends on the actual distance changes.Item Modeling and vision-based control of large-dimension cable-driven parallel robots using a multiple-camera setup(2019-08) Dallej, Tej; Gouttefarde, Marc; Andreff, Nicolas; Hervé, Pierre Elie; Martinet, Philippe; ROBOTICA_AUTOMAThis paper deals with the modeling and vision-based control of large-dimension cable-driven parallel robots. Inverse kinematics and instantaneous inverse kinematics models are derived from the elastic catenary cable modeling. These models turn out to be dependent on the pose of the mobile platform (end-effector), on the cable tangent directions and on the cable tensions. In order to control the motion of the robot, a position-based visual servo control is used, where the mobile platform pose is measured by vision and used for regulation. A multi-camera setup and load cells provide the aforementioned desired measurements, i.e., the mobile platform pose, the directions of the tangents to the cables, and the cable tensions. The proposed approach was validated in experiments on the large-dimension cable-driven parallel robot prototype CoGiRo of global dimensions 15 m × 11 m × 6 m (L × l × h). A maximum error of less than 1 cm in position and 0.5∘ in orientation was achieved. Moreover, in the case of cable-driven parallel robots larger than the prototype CoGiRo, simulations were conducted in order to assess the influence on the vision-based control of four instantaneous inverse kinematics models.