Parallel Elastic Actuation for Efcient

oFor legged devices, their ability of carrying pay- load is a necessity for a wide range of tasks. In this paper, we present a new approach of carrying payload by using a parallel elastic mechanism, which is able to carry payloads of at least 3 times of its bodyweight. Although the robot has no sensory feedback and consists of only two rigid bodies and one spring loaded joint, it is able to achieve efcient and stable forward hopping for a wide range of attached payload. The presented payload carrier ETH Cargo is based on the further development of our platform CHIARO for the payload range between 0 and 100kg. After parameter optimization using simulations, a series of real world experiments prove stable and high efciency hopping of the prototype over a wide range of payloads. I. INTRODUCTION

[1]  Zhuohua Shen,et al.  Towards the Understanding of Hip Torque and Leg Damping Effects on Model Stability , 2012 .

[2]  Martin Buehler,et al.  Stable open loop walking in quadruped robots with stick legs , 1999, Proceedings 1999 IEEE International Conference on Robotics and Automation (Cat. No.99CH36288C).

[3]  Martin Buehler,et al.  Controlled passive dynamic running experiments with the ARL-monopod II , 2006, IEEE Transactions on Robotics.

[4]  André Seyfarth,et al.  A comparison of parallel- and series elastic elements in an actuator for mimicking human ankle joint in walking and running , 2012, 2012 IEEE International Conference on Robotics and Automation.

[5]  Jonathan E. Clark,et al.  iSprawl: Design and Tuning for High-speed Autonomous Open-loop Running , 2006, Int. J. Robotics Res..

[6]  C. Glocker,et al.  Formulation and Preparation for Numerical Evaluation of Linear Complementarity Systems in Dynamics , 2005 .

[7]  Fumiya Iida,et al.  Self-stable one-legged hopping using a curved foot , 2014, 2014 IEEE International Conference on Robotics and Automation (ICRA).

[8]  Marc H. Raibert,et al.  Legged Robots That Balance , 1986, IEEE Expert.

[9]  Pei-Chun Lin,et al.  A simple running model with rolling contact and its role as a template for dynamic locomotion on a hexapod robot , 2014, Bioinspiration & biomimetics.

[10]  Jonathan E. Clark,et al.  A reduced-order dynamical model for running with curved legs , 2012, 2012 IEEE International Conference on Robotics and Automation.

[11]  Leonid B. Freidovich,et al.  Parallel Elastic Actuators as a Control Tool for Preplanned Trajectories of Underactuated Mechanical Systems , 2010, Int. J. Robotics Res..

[12]  Russ Tedrake,et al.  Efficient Bipedal Robots Based on Passive-Dynamic Walkers , 2005, Science.

[13]  Ronald S. Fearing,et al.  Sliding and hopping gaits for the underactuated Acrobot , 1998, IEEE Trans. Robotics Autom..

[14]  Justin Seipel,et al.  A simple model for clock-actuated legged locomotion , 2007 .