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A robot took a surgical retractor from a surgeon's hand with no real-world training data at all

AspireAI community · arXiv (2610.38234)
Surgeon-robot collaboration needs the robot to take over an instrument mid-procedure, and imitation learning normally demands expensive real demonstrations. SimRetract reports the first zero-shot sim-to-real transfer for that handoff: a policy trained only on simulated demonstrations takes a retractor from a surgeon's hand and preserves retraction at the moment of handoff, with no human demonstrations and no real-world fine-tuning. Deployed zero-shot, it grasped the retractor in 90 percent of 50 surgeon-defined phantom presentations and preserved retraction at handoff in 78 percent. The ablation is the interesting part - across ten policy configurations and 1,200 trials the authors localise the sim-to-real gap to specific components, and on the real robot removing the instrument mask alone collapses performance to 22 percent grasped and 12 percent held. The limit is honest and important: this is a phantom retractor, not live surgery.
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