IEEE Robotics & Automation Magazine - September 2018 - 60

system for deciding which action a robotic agent should
accomplish based on ethical principles [13]. The target application is elder care, and the target robotic system is TiaGO
(PAL Robotics). Proof of
concept is currently perAll of the code and modules formed using Nao. The
ethical engine continuously reevaluates the situused are based on wellation as observed by the
known accessible libraries, robot by connecting to
Playful's shared memory.
Via the evaluations it
part of the roboticist's
interfaces with, it sets the
priority of the higher-level
standard tool kit.
subtrees based on their
ethical desirability. Details
may be found in [14], a presentation video is online [19], and
the latest results are being prepared for publication. The success of this approach would enhance the reactivity displayed
by robots without sacrificing the framework's ability to interface with other advanced decision-making algorithms.
Conclusions
Playful is a software creation for behavior engineering whose
front end is a scripting language based on a reactive programming paradigm. It supports the development of simple,
clear, and well-structured code that brings robots to life.
Unlike other complex software and robotic architectures,
Playful is easy to use and deploy. It uses a five-keyword
scripting language that supports the rapid definition of
dynamic behavior trees of arbitrary complexity. Playful not
only allows for specifying the desired logic, but it expresses
the flow of information that should be applied at runtime. As
a result, reactive behavior can be created using expressive
instructions. Playful is agnostic regarding the middleware
and the robotic platform it runs on, making it a convenient
tool for a wide range of applications.
Acknowledgments
This research was supported in part by the Max Planck Society, National Science Foundation (grants IIS-1205249, IIS1017134, and EECS-0926052), the Office of Naval Research,
and the Okawa Foundation.
References
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Available: https://youtu.be/V8utFzn7DJk

Vincent Berenz, Autonomous Motion Department, Max
Planck Institute for Intelligent Systems, Tübingen, Germany. E-mail: vberenz@tuebingen.mpg.de.
Stefan Schaal, Autonomous Motion Department, Max Planck
Institute for Intelligent Systems, Tübingen, Germany, and
Computational Learning and Motor Control Lab, University
of Southern California, Los Angeles, United States. E-mail:
sschaal@usc.edu.
http://www-clmc.usc.edu/publications/S/schaal-TRSL.pdf http://playful.is.tuebingen.mpg.de http://youtu.be/Kb6O0KKXKp8 http://youtu.be/784eL6uSKbk http://youtu.be/ivJ8ZdUPOPo http://youtu.be/V8utFzn7DJk
IEEE Robotics & Automation Magazine - September 2018

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