Design project carried out under the supervision of Prof. Zhang Ming Hui at Shagdong University of Science and technology China.
Human hand is a major organ of human body and its anatomy is very complex. The human hand has 27 Degrees of freedom (DOF). This number can be justified by the complexity and capability of the human hand. These 27 DOFs are actuated by 29 muscles driving the 19 bones and 19 articulations associated with them. A Dexterous hand is developed to obtain 16 DOFs through the control of 16 pneumatic actuators. The pneumatic actuators were selected base on the following calculations which is done for a 100 mm Diameter sphere.
(These calculations are based on a bachelor thesis completed under the supervision of Prof. Zhang Ming Hui) The index finger position and acting forces are calculated based on F1 and F2. Those values are then used to select the actuator. According to the force requirement a contracting diaphragm type FESTO pneumatic actuator was selected for the application. More information regarding the force calculations and actuator selection can be found from the URLs mentioned at the end of this article. The fingers are controlled using artificial tendons which are connected to the pneumatic actuators as shown in Figure 1.
Figure 1 : Index finger artificial tendon arrangement
Figure 2 illustrates two grasping patterns of the designed prosthetic. The Prosthetic hand is designed to obtain five grasping patterns which are Cylindrical, Tip, Hook, Spherical and Lateral. The figure showcase the gripping operation of a spherical and cylindrical object.
Figure 2 : Grasping a sphere and a cylinder with a 100 mm diameter
I am working on some design aspects and focusing on improvements for the control of the Prosthetic.
Supervised by:
Prof. Zhang Ming Hui
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