An online method for tight-tolerance insertion tasks for string and rope

Abstract

This paper presents a fast tight-tolerance threading technique for string and rope. Instead of relying on simulations of these deformable objects to plan a path or compute control actions, we control the movement of the string with a virtual magnetic vector field emanating from the narrow openings we wish to thread through. We compute an approximate Jacobian to move the tip of the string through the vector field and propose a method to promote alignment of the head of the string to the opening. We also propose a method for re-grasping the string based on the relationship between the string's configuration, the orientation of the opening, and direction of gravity. This re-grasping method in conjunction with our controller can be used to thread the string through a sequence of openings. We evaluated our method in simulation (with simulated sensor noise) and on the Da Vinci surgical robot. Our results suggest that our method is quite robust to errors in sensing, and is capable of real-world threading tasks with the da Vinci robot, where the diameter of the string (3.5mm) and opening (4.9mm) differ by only 1.4 mm.978-1-4799-6923-4/15/$31.00 ©2015 IEEE

Robotic Manipulation of Elongated and Elastic Objects

“…Early models of deformable linear objects were designed based on the analysis of the physics of the phenomenons that govern the motion of the DLO. In the literature, there are several approaches to physics-based DLO modeling, like (i) Finite Element Method (FEM) [31], [12], (ii) continuous elastic rod models [32], [17], (iii) multi-body models [33], [34], or (iv) jacobian-based models [35], [8], each of which with its pros and cons [36], [37].…”

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Data-Driven Robotic Manipulation of Cloth-like Deformable Objects: The Present, Challenges and Future Prospects

“…We hope this review can provide a comprehensive snapshot of the current state of the art in this field and function as a development manual for the future progression of the field. In addition to the four major task families in this review, there are also some other tasks in the literature, including cloth hanging [20], bed making [21], ironing [22], rope insertion [23] and suturing [24]. Due to the limited number of relevant publications, we do not cover these in our review.…”