Thin plate manipulation by an under-actuated robotic soft gripper utilizing the environment

This paper presents methodologies for dexterous manipulation by an underactuated robotic soft gripper with a low DOF. While the softness and passive joints provide a stable grasp, the manipulations become challenging owing to the complexities of modeling and state estimation. To investigate the drawbacks, target manipulations using a support surface and gravity are defined in this study. By realizing the target manipulations, methodologies for utilizing both the support surface and gravity in manipulation are validated. For manipulation utilizing the support surface, the key states - at which the type of gripper motion primitive changes - are defined, and gripper motion at the key states is produced with a DNN-based motion generator. For manipulation utilizing gravity, the fall risk of the object is formulated as a constraint for a criterion function, and a parameters-online-exploration based methodology is adopted. The validity of the methodologies is demonstrated through several experiments.