Abstract
Japan faces a huge population decrease, which is especially alarming for labor issues in industrial fields, where factory automation is one solution. In fact, robots are already working in factories. However, the tasks they can perform are limited and cannot be changed easily because they depend on the surrounding environment. Most factory robots are only controlled by sequence control. To solve this problem, we developed a pneumatic robot arm driven by pneumatic actuators and constructed a wrist controller with no gravity. In this research, we propose a grasping strategy to pick up and place objects in industrial fields. We evaluated the dynamic characteristics of our wrist where various objects were grasped by the five -fingers of our robot arm. Based on this result, we constructed a wrist controller based on gravity. However, since we assume that the mass of an object is known, we also identified an object's mass using the change of the wrist angle after grasping it. As a result, PID control can be performed based on mass. By considering the wrist's movable region, we also got the robot's posture with which we obtained a restriction condition. By performing our specified task, we verified the validity of our proposed grasping strategy.
