Christopher D. Rahn

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Soft robotics: Biological inspiration, state of the art, and future research Deepak Trivedi a; Christopher D. Rahn a; William M. Kier b; Ian D. Walker c a Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, University Park, PA, USA b Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA(More)
This paper describes the results of field trials and associated testing of the OctArm series of multi-section continuous backbone "continuum" robots. This novel series of manipulators has recently (Spring 2005) undergone a series of trials including open-air and in-water field tests. Outcomes of the trials, in which the manipulators demonstrated the ability(More)
High-power lithium ion batteries are often rated with multiple current and voltage limits depending on the duration of the pulse event. These variable control limits, however, are difficult to realize in practice. In this paper, a linear Kalman filter based on a reduced order electrochemical model is designed to estimate internal battery potentials,(More)
This paper focuses on a class of robot manipulators termed “continuum” robots—robots that exhibit behavior similar to tentacles, trunks, and snakes. In previous work, we studied details of the mechanical design, kinematics, path-planning and small-deflection dynamics for continuum robots such as the Clemson “Tentacle Manipulator.” In this paper, we discuss(More)
This paper introduces a novel continuum manipulator consisting of two flexible sections connected by rigid base plates. Each section uses 6-8 opposing contracting and extending McKibben actuators to provide two-axis bending. The contracting/extending actuator pairs are sized and positioned to provide matched rotation and torque. The experimental manipulator(More)
In this paper, we describe our recent results in the development of a new class of soft, continuous backbone (“continuum”) robot manipulators. Our work is strongly motivated by the dexterous appendages found in cephalopods, particularly the arms and suckers of octopus, and the arms and tentacles of squid. Our ongoing investigation of these animals reveals(More)
Unlike traditional rigid linked robots, soft robotic manipulators can bend into a wide variety of complex shapes due to control inputs and gravitational loading. This paper presents a new approach for modeling soft robotic manipulators that incorporates the effect of material nonlinearities and distributed weight and payload. The model is geometrically(More)
Obstacle avoidance and object identification are important tasks for robots in unstructured environments. This paper develops an actuated whisker that determines contacted object profiles using a hub load cell. The shape calculation algorithm numerically integrates the elastica equations from the measured hub angle, displacement, forces, and torque until(More)
Contact sensors can provide high-information-density object surface sensing in harsh and/or opaque environments. This paper describes the design, modeling, control, and data processing of a contact imager consisting of a flexible whisker mounted on a two-axis robot through a load cell. The whisker sweeps around and into contact with unknown objects,(More)