Low-Contact Grasping of Soft Tissue Using a Novel Vortex Gripper

Manipulation of soft tissues remains one of the most prevalent tasks during minimally-invasive surgery. How-ever, surgical instruments for soft tissue grasping are primarily composed of hard, metallic materials which could result in tissue damage, if not properly used, as well as require large contact areas, both locally during grasping, as well as across the entire organ during large manipulation tasks (e.g., running bowel). As an alternative to traditional pinch-type graspers for tissue manipulation, vortex technology, currently found in manufacturing applications with fragile materials, could hold great promise. Vortex technology creates a negative pressure vortex through the ejection of compressed air through a specialized nozzle. This technology enables low-contact grasping of materials, including those at a distance and even through levitation of objects. Unlike suction cups, vortex grippers are also capable of grasping complex, non-smooth surfaces. In this paper, we present the design of a vortex gripper for soft tissue manipulation. We investigate the force characteristics of this gripper in grasping soft objects with four common shapes of varying radii of curvature and also evaluate the gripper's performance in grasping bio-inspired, artificial intestine tissue. Finally, the paper concludes with proposed design enhance-ments for future use in applications with biological tissue.