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Cutting skills are important for robots to acquire not only because of a need from kitchen automation, but also because of the technical challenge for robotic manipulation. Modeling of fracture and deformation during a cutting action, often based on the finite element method (FEM), provides the force and shape information used in knife control to implement a skill such as slice, chop, or dice. However, an object’s 3D mesh model can be computationally prohibitive for achieving a desired accuracy since numerous tiny elements must be used near the knife’s moving edge. To address this issue, we represent the object as evenly spaced slices normal to the cutting plane such that cutting of each slice requires only a 2D mesh. Fracture and force can be then interpolated between every two adjacent slices. Experiment with an Adept arm and an ATI force/torque (F/T) sensor has demonstrated reasonable accuracy in force and shape modeling.
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ICRA 2019 Digest Final
Effectiveness of cutting is measured by the ability to achieve material fracture with smooth knife movements. The work performed by a knife overcomes the material toughness, acts against the blade-material friction, and generates shape deformation. This paper studies how to control a 2-DOF robotic arm equipped with a force/torque sensor to cut through an object in a sequence of three moves: press, push, and slice. For each move, a separate control strategy in the Cartesian space is designed to incorporate contact and/or force constraints while following some prescribed trajectory. Experiments conducted over several types of natural foods have demonstrated smooth motions like would be commanded by a human hand.
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- Award ID(s):
- 1651792
- PAR ID:
- 10117630
- Date Published:
- Journal Name:
- International Conference on Robotics and Automation
- Page Range / eLocation ID:
- 3066 - 3072
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/ICRA.2019.8793894
