Design Optimisation and Control of Compliant Actuation Arrangements in Articulated Robots for Improved Energy Efficiency

The development of energy efficient actuation represents one of the biggest challenges in robotics research today. This letter presents the generalisation of design and control concepts for a recently introduced asymmetric compliant actuator, as well as its extension to multi-DoF articulated robotic systems. The actuator design consists of two actuation branches with significantly different stiffness and energy storage capacity properties driving a single joint. The letter studies and presents a novel method to select the design parameters of asymmetric compliant actuation schemes to improve the energy efficiency of multi-DoF articulated robots powered by this type of actuators. An optimisation problem is formulated to optimise the actuation parameters for energy efficient operation. Simulation studies performed on a 2-DoF leg as proof-of-concept demonstrate significant improvements in electrical energy efficiency and reduction in peak torque and electrical power requirements. Furthermore, biarticulated actuation arrangements are also investigated, and they are proven to further enhance the energy efficiency of the robotic leg.

[1]  Fumiya Iida,et al.  Bipedal walking and running with spring-like biarticular muscles. , 2008, Journal of biomechanics.

[2]  M. Tomizuka,et al.  Control of Rotary Series Elastic Actuator for Ideal Force-Mode Actuation in Human–Robot Interaction Applications , 2009, IEEE/ASME Transactions on Mechatronics.

[3]  Antonio Bicchi,et al.  Soft-actuators in cyclic motion: Analytical optimization of stiffness and pre-load , 2013, 2013 13th IEEE-RAS International Conference on Humanoid Robots (Humanoids).

[4]  Giorgio Grioli,et al.  VSA-II: a novel prototype of variable stiffness actuator for safe and performing robots interacting with humans , 2008, 2008 IEEE International Conference on Robotics and Automation.

[5]  Nikos G. Tsagarakis,et al.  Development and Control of a Compliant Asymmetric Antagonistic Actuator for Energy Efficient Mobility , 2016, IEEE/ASME Transactions on Mechatronics.

[6]  Yasuo Kuniyoshi,et al.  Mowgli: A Bipedal Jumping and Landing Robot with an Artificial Musculoskeletal System , 2007, Proceedings 2007 IEEE International Conference on Robotics and Automation.

[7]  Bram Vanderborght,et al.  MACCEPA, the mechanically adjustable compliance and controllable equilibrium position actuator: Design and implementation in a biped robot , 2007, Robotics Auton. Syst..

[8]  Atsushi Konno,et al.  Design and evaluation of a gravity compensation mechanism for a humanoid robot , 2007, 2007 IEEE/RSJ International Conference on Intelligent Robots and Systems.

[9]  Bram Vanderborght,et al.  Variable Recruitment of Parallel Elastic Elements: Series–Parallel Elastic Actuators (SPEA) With Dephased Mutilated Gears , 2015, IEEE/ASME Transactions on Mechatronics.

[10]  Stefano Stramigioli,et al.  The Variable Stiffness Actuator vsaUT-II: Mechanical Design, Modeling, and Identification , 2014, IEEE/ASME Transactions on Mechatronics.

[11]  Yoichi Hori,et al.  Comparing Approaches for Actuator Redundancy Resolution in Biarticularly-Actuated Robot Arms , 2014, IEEE/ASME Transactions on Mechatronics.

[12]  Sehoon Oh,et al.  Design and Control Considerations for High-Performance Series Elastic Actuators , 2014, IEEE/ASME Transactions on Mechatronics.

[13]  Nikolaos G. Tsagarakis,et al.  An asymmetric compliant antagonistic joint design for high performance mobility , 2013, 2013 IEEE/RSJ International Conference on Intelligent Robots and Systems.

[14]  Matthew M. Williamson,et al.  Series elastic actuators , 1995, Proceedings 1995 IEEE/RSJ International Conference on Intelligent Robots and Systems. Human Robot Interaction and Cooperative Robots.

[15]  V M Zatsiorsky,et al.  Tendon action of two-joint muscles: transfer of mechanical energy between joints during jumping, landing, and running. , 1994, Journal of biomechanics.

[16]  Gerrit Jan VAN INGEN SCHENAU,et al.  From rotation to translation: Constraints on multi-joint movements and the unique action of bi-articular muscles , 1989 .

[17]  Antonio Bicchi,et al.  Variable Stiffness Actuators for Fast and Safe Motion Control , 2003, ISRR.

[18]  Nikolaos G. Tsagarakis,et al.  Safe human robot interaction via energy regulation control , 2009, 2009 IEEE/RSJ International Conference on Intelligent Robots and Systems.

[19]  Alin Albu-Schäffer,et al.  On the Passivity-Based Impedance Control of Flexible Joint Robots , 2008, IEEE Transactions on Robotics.

[20]  Jadran Lenarčič,et al.  A Biarticulated Robotic Leg for Jumping Movements: Theory and Experiments , 2009 .

[21]  Nikolaos G. Tsagarakis,et al.  Compliant antagonistic joint tuning for gravitational load cancellation and improved efficient mobility , 2014, 2014 IEEE-RAS International Conference on Humanoid Robots.

[22]  Oliver Eiberger,et al.  The DLR FSJ: Energy based design of a variable stiffness joint , 2011, 2011 IEEE International Conference on Robotics and Automation.

[23]  Nikos G. Tsagarakis,et al.  A New Actuator With Adjustable Stiffness Based on a Variable Ratio Lever Mechanism , 2014, IEEE/ASME Transactions on Mechatronics.

[24]  Antonio Bicchi,et al.  Optimality principles in stiffness control: The VSA kick , 2012, 2012 IEEE International Conference on Robotics and Automation.

[25]  Nikolaos G. Tsagarakis,et al.  MACCEPA 2.0: compliant actuator used for energy efficient hopping robot Chobino1D , 2011, Auton. Robots.

[26]  Nikolaos G. Tsagarakis,et al.  MACCEPA 2.0: Adjustable compliant actuator with stiffening characteristic for energy efficient hopping , 2009, 2009 IEEE International Conference on Robotics and Automation.

[27]  M. Anthony Lewis,et al.  A robot leg based on mammalian muscle architecture , 2009, 2009 IEEE International Conference on Robotics and Biomimetics (ROBIO).

[28]  Nikolaos G. Tsagarakis,et al.  Exploiting natural dynamics for energy minimization using an Actuator with Adjustable Stiffness (AwAS) , 2011, 2011 IEEE International Conference on Robotics and Automation.