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arXiv · 2610.08421

Post-Grasp Kinematic Repair for Robotic Insertion via Object-in-Gripper Reorientation

Haegu Lee·Christoffer Sloth
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Abstract

A stable grasp does not guarantee kinematically feasible robotic insertion because the object-in-gripper transform may force the robot towards singularities or joint limits along the prescribed insertion path. We study post-grasp kinematic feasibility repair through object-in-gripper reorientation. Given an achieved grasp and a fixed insertion path, we seek a small reorientation that restores kinematic feasibility. Sequential IK can miss such candidates by following an unfavorable joint-space path, while the nonsmooth feasibility landscape makes the search computationally expensive. We evaluate candidates using a branch-aware IK graph that maximizes the minimum feasibility margin over the discretized insertion path and use a learned task-conditioned prior to improve query ordering. The selected reorientation is executed through tactile-based extrinsic manipulation. In UR5e simulations, the planner without learned ranking reduces mean reorientation over successful trials by 51.5% compared with grid-based sequential IK. Adding learned ranking reduces this planner's mean planning time by an additional 51.1%. Real-robot experiments validate the complete pipeline.

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Haegu Lee, Christoffer Sloth. 2026-10-06. Post-Grasp Kinematic Repair for Robotic Insertion via Object-in-Gripper Reorientation. https://arxiv.org/abs/2610.08421

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