Soft Robotics pp 120-133 | Cite as

Concepts of Softness for Legged Locomotion and Their Assessment

  • Andre Seyfarth
  • Katayon Radkhah
  • Oskar von Stryk
Conference paper


In human and animal locomotion, compliant structures play an essential role in the body and actuator design. Recently, researchers have started to exploit these compliant mechanisms in robotic systems with the goal to achieve the yet superior motions and performances of the biological counterpart. For instance, compliant actuators such as series elastic actuators (SEA) can help to improve the energy efficiency and the required peak power in powered prostheses and exoskeletons. However, muscle function is also associated with damping-like characteristics complementing the elastic function of the tendons operating in series to the muscle fibers. Carefully designed conceptual as well as detailed motion dynamics models are key to understanding the purposes of softness, i.e. elasticity and damping, in human and animal locomotion and to transfer these insights to the design and control of novel legged robots. Results for the design of compliant legged systems based on a series of conceptual biomechanical models are summarized. We discuss how these models compare to experimental observations of human locomotion and how these models could be used to guide the design of legged robots and also how to systematically evaluate and compare natural and robotic legged motions.


Human Walking Human Locomotion Legged Robot Legged Locomotion Animal Locomotion 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  • Andre Seyfarth
    • 1
  • Katayon Radkhah
    • 1
  • Oskar von Stryk
    • 1
  1. 1.Technische Universität DarmstadtDarmstadtGermany

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