Redundancy in Biology and Robotics: Potential of Kinematic Redundancy and its Interplay with Elasticity


Redundancy facilitates some of the most remarkable capabilities of humans, and is therefore omni-present in our physiology. The relationship between redundancy in robotics and biology is investigated in detail on the Series Elastic Dual-Motor Actuator (SEDMA), an actuator inspired by the kinematic redundancy exhibited by myofibrils. The actuator consists of two motors coupled to a single spring at the output. Such a system has a redundant degree of freedom, which can be exploited to optimize aspects such as accuracy, impedance, fault-tolerance and energy efficiency. To test its potential for human-like motions, the SEDMA actuator is implemented in a hopping robot. Experiments on a physical demonstrator show that the robot’s movement patterns resemble human squat jumps. We conclude that robots with bio-inspired actuator designs facilitate human-like movement, although current technical limitations may prevent them from reaching the same dynamic and energetic performance.

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Tom Verstraten is a postdoctoral fellow of the Research Foundation Flanders — Fonds voor Wetenschappelijk Onderzoek (FWO). Part of this work was funded by the European Commission starting grant SPEAR (no. 337596) and the DFG grants BE 5729/2 and BE 5729/1. We would like to thank Rustam Galljamov and Philipp Overath for their assistance with the demonstrator and the experiments.

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Correspondence to Tom Verstraten.

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Verstraten, T., Schumacher, C., Furnémont, R. et al. Redundancy in Biology and Robotics: Potential of Kinematic Redundancy and its Interplay with Elasticity. J Bionic Eng (2020).

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  • bioinspired
  • redundant actuation
  • series elastic actuation
  • hopping robots
  • energy efficiency
  • human physiology