Design of Flexible Pressure Sensor Applied to Mechanical Gripper

Abstract

Flexible electronic devices have emerged as a novel and popular research direction in the field of artificial intelligence, in which flexible sensor is an indispensable branch of flexible devices. In this article, a flexible pressure sensor is developed based on a liquid metal microchannel, which has the advantages of convenient measurement and easy integration. The sensor adopts Dragon skin 20 as the sensor matrix and Ga-In-Sn alloy as the conductive liquid. Meanwhile, there are two kinds of sensor structures are introduced which are the sensor only has a sensing layer and the sensor with an amplification layer. Through comparison of mechanical simulation models, the results suggest that adding the amplification layer structure can make the channel deformation more obvious, and the resistance change will be larger under the identical pressure, which indicating that adding amplification layer can effectively improve the sensitivity of sensor. We further demonstrate the basic characteristics of the sensor, and finally, it is proved by experiments that it can be installed on the mechanical gripper used to sense the pressure. This indicates that the flexible pressure sensor has relatively high sensitivity and the resistance value of sensor can well change with the size of pressure, which also indicates that the flexible pressure sensor has the possibility of applying in orchard manipulator picking for grasping force sensing to prevent peel breakage.