A Gripper for Flap Separation and Opening of Sealed Bags
Sergi Foix, Jaume Oriol Lladó, Carme Torras, Julia Borras Sol
AI summary
Problem
Separating and grasping thin, flexible layers of sealed sterile bags is a physically demanding, repetitive task for hospital nurses that standard robotic grippers cannot perform reliably.
Approach
The design uses an active dented-roller fingertip paired with compliant fingers that press the bag against a table, using controlled buckling to separate the top flap without dragging the bottom layer.
Key results
- Reliable separation and grasping of thin flexible flaps across multiple hospital materials
- Normal applied force identified as the primary performance variable
- Dual-gripper system successfully withstands forces required to robustly open sealed bag seals
- First robotic demonstration of automating the critical layer-separation step for sterile bag opening
Why it matters
Automates a highly repetitive, injury-prone hospital task, paving the way for safer, more efficient sterile supply preparation.
Abstract
Separating thin, flexible layers that must be in- dividually grasped is a common but challenging manipulation primitive for most off-the-shelf grippers. A prominent example arises in clinical settings: the opening of sterile flat pouches for the preparation of the operating room, where the first step is to separate and grasp the flaps. We present a novel gripper design and opening strategy that enables reliable flap separation and robust seal opening. This capability addresses a high-volume repetitive hospital procedure in which nurses manually open up to 240 bags per shift, a physically demanding task linked to musculoskeletal injuries. Our design combines an active dented-roller fingertip with compliant fingers that exploit environmental constraints to robustly grasp thin flexible flaps1. Experiments demonstrate that the proposed gripper reliably grasps and separates sealed bag flaps and other thin-layered materials from the hospital, the most sensitive variable affecting performance being the normal force applied. When two copies of the gripper grasp both flaps, the system withstands the forces needed to open the seals robustly. To our knowledge, this is one of the first demonstrations of robotic assistance to automate this repetitive, low-value, but critical hospital task.