Robotics is fast developing as a neoteric branch of engineering. As a vital topic in the field of robotics, robotic hands are widely studied by a variety of institutes and organizations because grasping and manipulation are the fundamental functionalities in application. Robotic hand is expected as flexible and versatile as human hand. However, due to the lack of information and the limitation of structures, plenty of conventional robot hands are far from intelligence. Therefore, assisted techniques are employed to improve the ability of information extraction, particularly the visual assistance. Hand-eye is a kind of visual assisted architecture which is used for detecting objects adapting to the end-effector. Even plenty of researches about the hand-eye robot were conducted, t...[ Read more ]

Robotics is fast developing as a neoteric branch of engineering. As a vital topic in the field of robotics, robotic hands are widely studied by a variety of institutes and organizations because grasping and manipulation are the fundamental functionalities in application. Robotic hand is expected as flexible and versatile as human hand. However, due to the lack of information and the limitation of structures, plenty of conventional robot hands are far from intelligence. Therefore, assisted techniques are employed to improve the ability of information extraction, particularly the visual assistance. Hand-eye is a kind of visual assisted architecture which is used for detecting objects adapting to the end-effector. Even plenty of researches about the hand-eye robot were conducted, the circumscribed field of view still remains to be a problem. Meanwhile, as the integration level of camera device grows rapidly, a more compact arrangement of the hand-eye device is expected and may solve the field of vision problem. Then the corresponding characteristics and benefits are to be investigated.

In this thesis, a multi-fingered robotic hand is developed with stereo cameras on palm which aims at precisely grasping objects and dexterously manipulating. The robotic hand design, stereo vision establishment and grasping theories are primarily concerned. Main issues are investigated and several methods are put forward to apply the stereo visual technology in robotic hand implementations. Firstly, the mechanism and transmission of hand are analyzed and designed to satisfy various requirements. Then, the corresponding closed-loop approach is proposed to control this robotic hand. On the other aspect, the stereo visual assistant is built on palm. To measure the absolute distance of objects, adequate methods of target localization are designed to match varied applying conditions. Moreover, the grasping theories are developed with an emphasis on the contacting stage, and the hand shrinking method is given in accordance with the designed system. Finally, for implementing the grasp with integrated platform, strategies and procedures are formulated, and the comparison is carried out as well.

Both analysis and experiments are conducted, and the obtained results verify the methods proposed in this thesis. It shows that the precision of the distance measured by stereo vision system can be higher than 2mm, and the performance of robotic hand grasping meets the requirements in practice.

Key words: multi-fingered robotic hand, stereo vision, versatility.