Soft Fingertip with Tactile Sensation for Detecting Grasping Orientation of Thin Object

The study proposed a sensitive soft fingertip based on magnetic flux density (MFD) changes to be applied to robot gripper for grasping and manipulating a thin object such as a circuit board. The fingertip consists of 5 neodymium magnets and a 3-axis Hall sensor. The cylindrical shape of fingertip was fabricated with 3D printer. When the board was pushed onto the fingertip, the applied force, push displacement and object orientation can be determined by analyzing the changes of MFD induced by the displacement of magnets. Finite element (FE) model was developed to simulate the fingertip's deformation and MFD distribution. Experimental validation was performed to validate the model. We conclude that the applied force and contact orientation of the board were able to be determined by sensor's output with a given push displacement. The ability of detecting fingertip's deformation and contact orientation made it high potential to be applied to robot grippers for handling task.

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