Gentle Grasping: A Method with Low-Cost Magnetic Tactile Sensors

Abstract

Human tactile capabilities enable the manipulation of various objects seamlessly in everyday life. We present a grasping strategy employing a two-fingered parallel gripper with a low-cost magnetic tactile sensor. The sensor provides three-dimensional force feedback during the grasping process. Using the tactile sensing, we can detect slip during the object's lift phase. We propose a force approximation technique that dynamically adjusts force increments to identify the critical slip threshold of objects. This allows the robot to maintain a stable grasp on the threshold where an unknown object is about to slip. We validated our approach through experiments involving 20 diverse everyday objects. The results demonstrate that our slip detection based on low-cost magnetic tactile sensors is effective and that the proposed force approximation method swiftly determines the critical slip threshold for various everyday objects.