Reducing Training Environments in Evolutionary Robotics Through Ecological Modularity

  • Collin CappelleEmail author
  • Anton Bernatskiy
  • Josh Bongard
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10384)


Due to the large number of evaluations required, evolutionary robotics experiments are generally conducted in simulated environments. One way to increase the generality of a robot’s behavior is to evolve it in multiple environments. These environment spaces can be defined by the number of free parameters (f) and the number of variations each free parameter can take (n). Each environment space then has \(n^f\) individual environments. For a robot to be fit in the environment space it must perform well in each of the \(n^f\) environments. Thus the number of environments grows exponentially as n and f are increased. To mitigate the problem of having to evolve a robot in each environment in the space we introduce the concept of ecological modularity. Ecological modularity is here defined as the robot’s modularity with respect to free parameters in its environment space. We show that if a robot is modular along m of the free parameters in its environment space, it only needs to be evolved in \(n^{f-m+1}\) environments to be fit in all of the \(n^f\) environments. This work thus presents a heretofore unknown relationship between the modularity of an agent and its ability to generalize evolved behaviors in new environments.



We like to acknowledge financial support from NSF awards PECASE-0953837 and INSPIRE-1344227 as well as the Army Research Office contract W911NF-16-1-0304. We also acknowledge computation provided by the Vermont Advanced Computing Core.


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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  • Collin Cappelle
    • 1
    Email author
  • Anton Bernatskiy
    • 1
  • Josh Bongard
    • 1
  1. 1.The University of VermontBurlingtonUSA

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