Dynamic Virtual Fixture Generation Based on Intra-Operative 3D Image Feedback in Robot-Assisted Minimally Invasive Thoracic Surgery

Abstract

This paper proposes a method for generating dynamic virtual fixtures with real-time 3D image feedback to facilitate human–robot collaboration in medical robotics. Seamless shared control in a dynamic environment, like that of a surgical field, remains challenging despite extensive research on collaborative control and planning. To address this problem, our method dynamically creates virtual fixtures to guide the manipulation of a trocar-placing robot arm using the force field generated by point cloud data from an RGB-D camera. Additionally, the “view scope” concept selectively determines the region for computational points, thereby reducing computational load. In a phantom experiment for robot-assisted port incision in minimally invasive thoracic surgery, our method demonstrates substantially improved accuracy for port placement, reducing error and completion time by 50% (p=1.06×10−2) and 35% (p=3.23×10−2), respectively. These results suggest that our proposed approach is promising in improving surgical human–robot collaboration.

Keywords

• virtual fixtures
• 3D image-guided robots
• virtual force field
• human–robot collaboration