Roddy: Rod Elasticity Incorporated into a Robot Manipulator for Rigid Tool Use around Rigid Environment

In order to enhance the capability of soft robot manipulator, we propose Roddy, a new type of soft robot system for manipulating a "rigid" tool softly. In Roddy, an elastic rod with a 6-axis force sensor is inserted in series between a rigid tool and a rigid robot manipulator. By utilizing the real-time shape estimation technology, Roddy can recognize the rigid tool position/orientation relative to a rigid environment with high accuracy and precision. Due to high compliance of Roddy, we can achieve accurate calibration of the manipulator tool relative to the environmental flat plane. Moreover, we can also achieve to map the location of obstacles on a plane by exploratory collisions. Based on this obstacle mapping algorithm, we demonstrate that Roddy can safely achieve quick scooping tasks where the rigid tool of the robot manipulator is continuously contact with the environmental rigid plane.