Development of an Optical Three-Axis Tactile Sensor for Object Handing Tasks in Humanoid Robot Navigation System

Autonomous navigation in walking robots requires that three main tasks be solved: self-localization, obstacle avoidance, and object handling. This report presents a development and application of an optical three-axis tactile sensor mounted on a robotic finger to perform object handling in a humanoid robot navigation system. Previously in this research, we proposed a basic humanoid robot navigation system called the groping locomotion method for a 21-dof humanoid robot, which is capable of defining self-localisation and obstacle avoidance. Recently, with the aim to determining physical properties and events through contact during object handling, we have been developing a novel optical three-axis tactile sensor capable of acquiring normal and shearing force. The tactile sensor system is combined with 3-dof robot finger system where the tactile sensor in mounted on the fingertip. Experiments were conducted using soft, hard, and spherical objects to evaluate the sensors performance. Experimental results reveal that the proposed optical three-axis tactile sensor system is capable of recognizing contact events and has the potential for application to humanoid robot hands for object handling purposes.