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This paper presents the usage of holonomic mobile humanoid manipulators to carry out autonomous tasks in industrial environments, according to the smart factory concept and the Industry 4.0 philosophy. The problem of transporting lengthy objects, taking into account mechanical limitations, the conditions for avoiding collisions, as well as the dext...
Contexts in source publication
Context 1
... contrast to the original design, the robot proposed in this work was equipped with a holonomic (3, 0)-type platform with two pairs of Mecanum wheels and the arms with four DOF. The model of the humanoid manipulator on its holonomic platform is shown in Figure 1. As can be seen, the robot consists of four main components: ...
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... R 4 are the joint angles of the left and right arms, respectively. The rotation axes of the independent joints of the torso (i.e., the axes for the first, second, and third joints) and all joint axes of left arm are shown in Figure 1; the rotation axes of the right arm are similar. As shown, the arms are located at the end of the torso, and their bases are rotated by an angle of β. ...
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... order to verify the effectiveness of the proposed algorithm, computer simulations involving the humanoid mobile manipulator, presented in Figure 1, were considered. The kinematic parameters of the robotic system corresponding to the DH parameters, collected in Table 1, are given as (all physical values are expressed in the SI system): ...
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... error is reduced during the third phase of the task and 571 finally the beam is placed precisely on the conveyor. To demonstrate the effectiveness of the obstacle avoidance approach, the distances of the robot and the transported beam from the obstacles in the workspace were calculated and are presented in Figures 10 and 11. As can be seen, at the beginning of the first phase, the robot was close to the CNC machine and control panel. ...
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... beam was gripped, and the second phase of the task then began. In this phase, the robot lifted the beam, avoiding a collision with the container (see Figure 11), and moved it towards the roller conveyor. This phase ended when the beam was approximately 0.5 m above the conveyor. ...
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... phase ended when the beam was approximately 0.5 m above the conveyor. Finally, in the last phase, the robot placed the beam on the conveyor, so the distances of the robot end-effectors and the object from the conveyor tended to zero (see the third part in Figures 10 and 11). As can be seen, the distances from the obstacles during whole motion were greater than zero, so the trajectory, determined according to the proposed approach, was collision-free. ...
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... The values of the joint angles, obtained for the torso and the left and right arm, were mean normalized, i.e., scaled to a −0.5 to 0.5 range, in order to fit in the same range, and are presented in Figures 12-14, respectively. As can be seen, according to the assumed form of mapping D M (q), all values remained as close as possible to the middle of the ranges permitted. ...
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... values close to the limitations resulted from the given initial configuration or the requirements of the task, such as obstacle avoidance or reaching a given position and orientation. and presented in Figures 12, 13 and 14, respectively. As can be seen, according to the 589 assumed form of mapping D M (q), all values remain as close as possible to the middle 590 of the ranges permitted. ...
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... was shown in Section 2.4, in addition to the fulfillment of the mechanical and collision avoidance constraints, the maximization of the manipulability measure of the humanoid arms was considered as a secondary objective. Changes of this measure are shown in Figure 15. As can be seen, the manipulability measure at the beginning of the motion was relatively small; however, during the task execution, the effect of the secondary objective term could be seen, and the values of this measure increased. ...
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... clear decrease of the measure could be noticed around the 12th second, during the first phase of the task. This was a consequence of the reconfiguration necessary to grasp the beam resulting from the primary task; however, as is shown in Figure 15, after reaching the appropriate configuration, the manipulability measure increased. The second decrease occurred in the second phase when the robot avoided colliding with the container when lifting the beam. ...
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