Edge tracing is important in manipulating deformable objects to reveal their original shape. In this paper, we propose a unique and improved tracing manipulation for towel spreading, an example of a deformable object using two robot arms with sensors-equipped grippers and a CCD camera. Tracing in this paper context involves tracing the towel’s edge. Robot arm movement is based on feedback from sensors and from images from the CCD camera. Our proposed tracing manipulation ensures that both corners grasped by robot are adjacent and not across, enabling the towel to be successfully spread. Experimental results from spreading rectangular towels with different thickness, stiffness, smoothness, and color using our improved tracing manipulation demonstrated that our proposal is also robust.

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