A Constraint Programming Approach to Multi-Robot Task Allocation and Scheduling in Retirement Homes

  • Kyle E. C. BoothEmail author
  • Goldie Nejat
  • J. Christopher Beck
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9892)


We study the application of constraint programming (CP) to the planning and scheduling of multiple social robots interacting with residents in a retirement home. The robots autonomously organize and facilitate group and individual activities among residents. The application is a multi-robot task allocation and scheduling problem in which task plans must be determined that integrate with resident schedules. The problem involves reasoning about disjoint time windows, inter-schedule task dependencies, user and robot travel times, as well as robot energy levels. We propose mixed-integer programming (MIP) and CP approaches for this problem and investigate methods for improving our initial CP approach using symmetry breaking, variable ordering heuristics, and large neighbourhood search. We introduce a relaxed CP model for determining provable bounds on solution quality. Experiments indicate substantial superiority of the initial CP approach over MIP, and subsequent significant improvements in the CP approach through our manipulations. This work is one of the few, of which we are aware, that applies CP to multi-robot task allocation and scheduling problems. Our results demonstrate the promise of CP scheduling technology as a general optimization infrastructure for such problems.


Multi-robot Task Allocation (MRTA) Retirement Home Large Neighborhood Search (LNS) Disjoint Time Windows Robot Energy 
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.



The authors would like to thank the Natural Sciences & Engineering Research Council of Canada (NSERC), Dr. Robot Inc., and the Canada Research Chairs (CRC) Program.


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Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  • Kyle E. C. Booth
    • 1
    Email author
  • Goldie Nejat
    • 1
  • J. Christopher Beck
    • 1
  1. 1.Department of Mechanical and Industrial EngineeringUniversity of TorontoTorontoCanada

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