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Grasping in dynamic environments presents a unique set of challenges. A stable and reachable grasp can become unreachable and unstable as the target object moves, motion planning needs to be adaptive and in real time, the delay in computation makes prediction necessary. In this paper, we present a dynamic grasping framework that is reachabilityaware and motion-aware. Specifically, we model the reachability space of the robot using a signed distance field which enables us to quickly screen unreachable grasps. Also, we train a neural network to predict the grasp quality conditioned on the current motion of the target. Using these as ranking functions, we quickly filter a large grasp database to a few grasps in real time. In addition, we present a seeding approach for arm motion generation that utilizes solution from previous time step. This quickly generates a new arm trajectory that is close to the previous plan and prevents fluctuation. We implement a recurrent neural network (RNN) for modelling and predicting the object motion. Our extensive experiments demonstrate the importance of each of these components and we validate our pipeline on a real robot.
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This content will become publicly available on December 12, 2026
Loop closure grasping: Topological transformations enable strong, gentle, and versatile grasps
Grasping mechanisms must both create and subsequently hold grasps that permit safe and effective object manipulation. Existing mechanisms address the different functional requirements of grasp creation and grasp holding using a single morphology but have yet to achieve the simultaneous strength, gentleness, and versatility needed for many applications. We present “loop closure grasping,” a class of robotic grasping that addresses these different functional requirements through topological transformations between open-loop and closed-loop morphologies. We formalize these morphologies for grasping, formulate the loop closure grasping method, and present principles and a design architecture that we implement using soft growing inflated beams, winches, and clamps. The mechanisms’ initial open-loop topology enables versatile grasp creation via unencumbered tip movement, and closing the loop enables strong and gentle holding with effectively infinite bending compliance. Loop closure grasping circumvents the tradeoffs of single-morphology designs, enabling grasps involving historically challenging objects, environments, and configurations.
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- PAR ID:
- 10691775
- Publisher / Repository:
- Science
- Date Published:
- Journal Name:
- Science Advances
- Volume:
- 11
- Issue:
- 50
- ISSN:
- 2375-2548
- Page Range / eLocation ID:
- eady9581
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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