Chobit Hand: A Gripper for A Linear-Shaped Food Adjusting Precise Weight of Serving

In many cases in the field of food processing and production, serving is still done by workers rather than by robots. However, linear foods such as spaghetti need to be served precisely and quantitatively, which is difficult for a conventional robot gripper. Therefore, in this study, we developed a new end-effector that can grasp a small amount of linear food with high accuracy. By installing several fingers on this end-effector and driving a fixed number of fingers according to the error between the target and the measured weight of food, we can compensate for the error. After investigating several parameters and selecting the optimal finger shape, the end-effector grasped one noodle with a success rate of nearly 90%. Next, we introduced capacitance sensors to all fingers to detect successful grasping. The sensors enabled us to construct a system that compensates for the weight errors in the amount of serving by detecting whether each finger is grasping and controlling the number of fingers that open accordingly. We conducted experiments with spaghetti and succeeded in adjusting the amount of food with an error of less than 2g.