Parametrically Modeled DH Table for Soft Robot Kinematics: Case Study for A Soft Gripper

Recently, researches and innovations were greatly developed in the field of soft robotics due to the advantages of higher flexibility and safer operations. Researchers have designed new materials, new manufacturing methodologies and advanced control techniques for soft robots. Some commercial products such as soft grippers are now available in the market and applied in the area of agriculture, medicine, machinery, etc. This paper aims to show how to mathematically describe the motions of soft robots. A method of parametrically modeled Denavit-Hartenberg (DH) parameters was used for soft robot kinematic analysis. A soft finger with soft polydimethylsiloxane (PDMS) body and rigid polylactic acid (PLA) bone structures were made by a molding process and actuated by cable. The bending motion of the soft finger changed the link angle and the link length of the soft finger, which were parametrically modeled. This case study showed the DH parameters of the soft finger nonlinearly changed with respect to the control parameter.