Real-time Capable Learning-based Visual Tool Pose Correction via Differentiable Simulation
Shuyuan Yang, Zonghe Chua
TL;DR
This work tackles the challenge of robust, real-time end-effector pose estimation for cable-driven MIS robots by coupling a vision-transformer estimator with a fully differentiable simulation-rendering pipeline. By training on synthetic data generated through a differentiable simulator, the approach learns corrections to the ECM-to-PSM transform and the last four PSM joints from endoscopic tool masks and noisy priors, enabling online pose correction. The method achieves near real-time performance and outperforms a gradient-descent baseline in accuracy and speed within simulation, highlighting its potential for sim-to-real transfer. Future work focuses on domain adaptation and real-world validation to realize autonomous, vision-assisted tool pose correction in clinical settings.
Abstract
Autonomy in Minimally Invasive Robotic Surgery (MIRS) has the potential to reduce surgeon cognitive and task load, thereby increasing procedural efficiency. However, implementing accurate autonomous control can be difficult due to poor end-effector proprioception, a limitation of their cable-driven mechanisms. Although the robot may have joint encoders for the end-effector pose calculation, various non-idealities make the entire kinematics chain inaccurate. Modern vision-based pose estimation methods lack real-time capability or can be hard to train and generalize. In this work, we demonstrate a real-time capable, vision transformer-based pose estimation approach that is trained using end-to-end differentiable kinematics and rendering in simulation. We demonstrate the potential of this method to correct for noisy pose estimates in simulation, with the longer term goal of verifying the sim-to-real transferability of our approach.
