Experimental investigation and theoretical modeling on Bernoulli gripper using water for supply power enhancement

Abstract

Bernoulli gripper is a fluid-driven vacuum suction device, widely used in automated production lines, with suction force regarded as its key mechanical indicator. Previous design methods for optimizing the structure and parameters showed very limited enhancement in suction force due to the compressibility of air, which limits the supply pressure and supply power. Therefore, this study proposes an innovative design for replacing the fluid medium from compressible gas to incompressible liquid (e.g., water). It was experimentally validated that the gripper using water can increase the supply power several times and the suction force dozens of times compared with that using air. Then, the pressure distribution and flow field of the gripper were investigated experimentally, implying that the flow field exists in the water-film zone and the bubble zone, with radial lines of water flow of equal cross section formed in the bubble zone. Furthermore, a model of pressure distribution was established, including the water-film zone, the bubble zone, and the boundary between the two. The theoretical results were basically consistent with the experimental results. This study provides an innovative idea, theoretical model, and experimental data for the optimal design and application of the Bernoulli gripper.