Production of Grippers Working with Bernoulli’s Principle for Laparoscopic Surgery and Optimization of Parameters that Affect Air Speed Required for Pulling Force

Abstract

Laparoscopic surgeries are conducted using instruments and a camera inserted through tubes into the body, without conventional large incisions. Existing grippers used in laparoscopy are long and have a geared structure. Since tissues should be compressed for adequate gripping, grippers increase the risk of tissue damage. In this study, to prevent tissue damage, non-contact grippers were produced and tested for gripping and lifting performance in terms of air speed. Non-contact gripping was achieved by vacuum by reducing the pressure between the compressed air sent to the gripper operating based on Bernoulli’s principle and the object to be lifted by the gripper surface. Each gripper’s air velocity required to generate buoyancy was optimized using the Taguchi method to investigate usability. By using the Taguchi L₁₆ orthogonal array, 16 experiments were conducted using 4 grippers, 4 air pressure conditions and 4 flow rates designed for air speed tests in increasing buoyancy. The results were analyzed using signal-to-noise ratio, analysis of variance and three-dimensional plots. The optimum combination consisted of 6.5 bar pressure and 3.4 m³/h air flow. The most effective factor was the gripper type. The results are important in preventing organ injuries when lifting flexible and sensitive tissues in laparoscopic surgery.