Grasping in unstructured environments is one of the most challenging issues currently facing robotics. The inherent uncertainty about the properties of the target object and its surroundings compels the use of robot hands, which typically involve complex hands, require elaborate sensor suites, and are difficult to control. For this purpose, in this paper combining the kinematic structure of a three and two links finger for design and fabrication of robotic gripper will be evaluated. First, the

more »

... hallenges associated with grasping by careful mechanical design of gripper are analyzed. Then, the design and fabrication of a sample gripper by combining a three-links finger similar to the human index finger and a two-links finger similar to the thumb are described. In the following, the performance of this hand for grasping various objects will be examined. The results show that with two fingers and simple design, without the need for the complex control, c various objects can be grasped successfully. Also, the results demonstrate that compared with the previous researches and by proximity to the kinematic structure of the human hand fingers, by combining two with three link fingers this gripper will have a better performance than the previous symmetric gripper for successfully grasping large objects.