STITCH 2.0: Extending Augmented Suturing with EKF Needle Estimation and Thread Management
Kush Hari, Ziyang Chen, Hansoul Kim, Ken Goldberg
AI summary
Problem
Previous robot-assisted suturing systems struggle with inaccurate needle tracking, thread tangling, and uneven suture placement, preventing reliable full wound closure.
Approach
The system integrates an Extended Kalman Filter for precise 6D needle pose estimation, automated 3D suture alignment, and coordinated thread management to guide a surgical robot through consistent suture throws.
Key results
- Achieved 74.4% average wound closure with 4.87 sutures per trial without intervention
- Reduced execution time by 38% while increasing suture count by 66% compared to STITCH 1.0
- Reached 100% wound closure averaging six sutures when allowing two human interventions
- Introduced automated 3D suture alignment and EKF-based needle tracking to eliminate manual setup and improve pose accuracy
Why it matters
This advancement brings semi-autonomous surgical robots closer to clinical adoption by reliably automating a tedious, skill-dependent subtask to improve patient outcomes and reduce surgeon fatigue.
Abstract
Surgical suturing is a high-precision task that im- pacts patient healing and scarring. Suturing skill varies widely between surgeons, highlighting the need for robot assistance. Previous robot suturing works, such as STITCH 1.0 [1], struggle to fully close wounds due to inaccurate needle tracking and poor thread management. To address these challenges, we present STITCH 2.0, an elevated augmented dexterity pipeline with seven improvements including: improved EKF needle pose estimation, new thread untangling methods, and an automated 3D suture alignment algorithm. Experimental results over 15 trials find that STITCH 2.0 on average achieves 74.4% wound closure with 4.87 sutures per trial, representing 66% more sutures in 38% less time compared to the previous baseline. When two human interventions are allowed, STITCH 2.0 averages six sutures with 100% wound closure rate.