Multifunctional forceps for use in endoscopic surgery-initial design, prototype, and testing

This paper presents a 3.0 mm diameter multifunctional endoscopic forceps design for use in minimally invasive flexible endoscopic surgical procedures. Multifunctional capabilities including grasping, spreading, and cauterizing tissue are demonstrated experimentally and compared to commercially available forceps. Models of the proposed design predict considerable improvements in opening range (140%) and force application (87%) for both grasping and spreading when compared to currently used endoscopic forceps. Several of the tool's design characteristics promote fail-safe malfunctions, including locking before catastrophic failure and a decreased likelihood in detached parts. Initial benchtop testing shows good agreement between prototype performance and model prediction. Frictional losses experienced during testing were found to depend on load orientation.