A Face Attention Technique for a Robot Able to Interpret Facial Expressions

  • Carlos Simplício
  • José Prado
  • Jorge Dias
Part of the IFIP Advances in Information and Communication Technology book series (IFIPAICT, volume 314)


Automatic facial expressions recognition using vision is an important subject towards human-robot interaction. Here is proposed a human face focus of attention technique and a facial expressions classifier (a Dynamic Bayesian Network) to incorporate in an autonomous mobile agent whose hardware is composed by a robotic platform and a robotic head. The focus of attention technique is based on the symmetry presented by human faces. By using the output of this module the autonomous agent keeps always targeting the human face frontally. In order to accomplish this, the robot platform performs an arc centered at the human; thus the robotic head, when necessary, moves synchronized. In the proposed probabilistic classifier the information is propagated, from the previous instant, in a lower level of the network, to the current instant. Moreover, to recognize facial expressions are used not only positive evidences but also negative.


Facial Symmetry Focus of Attention Dynamic Bayesian Network 


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Copyright information

© IFIP International Federation for Information Processing 2010

Authors and Affiliations

  • Carlos Simplício
    • 1
    • 2
  • José Prado
    • 1
  • Jorge Dias
    • 1
  1. 1.Institute of Systems and Robotics, at Department of Electrical Engineering and Computers of University of CoimbraCoimbraPortugal
  2. 2.School of Technology and Management of Institute Polytechnic of LeiriaLeiriaPortugal

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