An Investigation of the Intrinsic Force Sensing Capabilities of Continuum Robots

-- This paper presents the theoretical analysis and the experimental validation of the force sensing capabilities of continuum robots. These robots employ super-elastic NiTi backbones and actuation redundancy. The paper uses screw theory to analyze the limitations and to provide geometric interpretation to the sensible wrenches. The analysis is based on the singular value decomposition of the Jacobian mapping between the configuration space and the twist space of the end effector. The results show that the sensible wrenches belong to a two-dimensional screw system and the insensible wrenches belong to a four-dimensional screw system. The theory presented in this paper is validated through simulations and experiments. It is shown that the force sensing errors have an average of 0.34 grams with a standard deviation of 0.83 grams. Another experiment of generating the stiffness map of a silicone strip suggests possible medical application of palpation for tumor detection. The presented stu...

• Type: Journal
• Year: 2008
• Where: TROB
• Authors: Kai Xu 0005, Nabil Simaan
• Keywords: Sensible Wrenches, Singular Value Decomposition, Super-elastic Niti Backbones, TROB 2008