Abstract
Cutting changes both the shape and topology of deformable objects, making accurate simulation challenging for robotic manipulation. A simulator must track the cutting tool as a cut develops, preserve the resulting discontinuities after tool withdrawal, and enable newly exposed surfaces to interact with the tool and with each other. Existing formulations often prescribe cut surfaces in advance or couple material separation to auxiliary geometric fields. We introduce BladeMaster, a GPU-accelerated cutting framework based on the total Lagrangian material point method (TLMPM). Our key idea is to encode the cutting history directly on material points through persistent side labels generated online from the blade geometry. These labels govern particle–grid coupling, preserving connectivity within intact material while preventing spurious coupling across cut faces after tool withdrawal. Our formulation supports progressive and intersecting cuts without predefined cut surfaces or particle duplication. Material–material contact enables cut surfaces to recontact and slide against each other without reconnecting, while two-way tool–material coupling allows material reaction forces to influence tool motion. Experiments demonstrate tool-driven cutting followed by manipulation, with faster-than-real-time performance on representative tasks.
Robotic Cutting and Manipulation
The robot cuts a banana and pushes the pieces aside. Simulation and the real robot follow the same knife trajectory.
Simulation Results
Sequential Slicing
The knife cuts thin slices that topple under gravity and accumulate on the cutting board. Material below the blade remains connected until the cut is complete.
Knife-tip Scoring at Two Depths
The same cross-shaped knife-tip path is repeated at two penetration depths. Both create intersecting partial cuts, leaving the material connected underneath.
Gravity-driven Cutting
The knife falls under gravity as material reaction forces rotate it and deflect its path. The cut surface is generated online along this evolving trajectory. With lower blade sharpness, the knife does not cut through the block.
Two-way Tool–Material Coupling
Material reactions decelerate the freely moving knives. Higher initial speeds produce deeper penetration.
Comparisons
Slice Lifting
BladeMaster's persistent discontinuities keep the cut slice separated after knife withdrawal, allowing it to be lifted independently. With identical particle sampling and knife motion, the single-field baseline pulls the surrounding material upward.
Comparison with CRESSim-MPM(Ou and Tavakoli, 2025)
Independent manipulation
After two cuts, only the left piece receives an initial leftward velocity. With BladeMaster, it moves away while the middle and right pieces remain near their original positions. In CRESSim-MPM, the middle and right pieces are also pulled leftward. This demonstrates that BladeMaster supports independent manipulation after successive cuts.
| Measurement | BladeMaster | CRESSim-MPM |
|---|---|---|
| Mean cut gapFirst cut at half depth · 0.5 mm-thick blade | 0.654 mm | 4.059 mm |
| Volume contractionMiddle piece after both cuts | 0.506% | 8.746% |
BibTeX
@misc{yang2026blademasterrealtimeroboticcutting,
title = {BladeMaster: Real-Time Robotic Cutting
Simulation with Online-Generated
Persistent Discontinuities},
author = {Zhanyu Yang and Yunuo Chen and
Yanjia Huang and Joseph Masterjohn and
Yin Yang and Chenfanfu Jiang},
year = {2026},
eprint = {2609.27342},
archivePrefix = {arXiv},
primaryClass = {cs.RO},
url = {https://arxiv.org/abs/2609.27342}
}