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Abstract

Part I of this article showed that making robotic fingers from soft materials helps them cope with the following three prob lems. First, the impact forces that occur at the instant of grasping are reduced. Second, commonly used objects with uneven surfaces can be grasped comfortably due to the confor mal nature of the soft fingers. Third, the repeated strains that are induced during manipulations are dissipated. The problem to solve now is that of modeling and controlling the overall impedance of a soft finger or of a finger that has a soft tip. This is the issue addressed in this part.

This part presents the experimental determination of the pas sive impedance parameters of a soft (gel-filled) fingertip and formulates an approach to account for the soft fingertip model when controlling the overall impedance of a finger that carries the soft tip. The approach is demonstrated via four experi ments, each with a unique goal. Also showed experimentally is how the presence of passive damping helps reduce the peak impact forces that occur as a rigid object is grasped by the fingers of a robotic hand.

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References

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Soft Robotic Fingertips

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