Trajectory Optimization for High-Power Robots with Motor Temperature Constraints

  • Wei Xin Tan
  • Martim BrandãoEmail author
  • Kenji Hashimoto
  • Atsuo Takanishi
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10965)


Modeling heat transfer is an important problem in high-power electrical robots as the increase of motor temperature leads to both lower energy efficiency and the risk of motor damage. Power consumption itself is a strong restriction in these robots especially for battery-powered robots such as those used in disaster-response. In this paper, we propose to reduce power consumption and temperature for robots with high-power DC actuators without cooling systems only through motion planning. We first propose a parametric thermal model for brushless DC motors which accounts for the relationship between internal and external temperature and motor thermal resistances. Then, we introduce temperature variables and a thermal model constraint on a trajectory optimization problem which allows for power consumption minimization or the enforcing of temperature bounds during motion planning. We show that the approach leads to qualitatively different motion compared to typical cost function choices, as well as energy consumption gains of up to 40%.


Trajectory optimization Motion planning Legged robots Temperature Thermal models 



This work was supported by ImPACT TRC Program of Council for Science, Technology and Innovation (Cabinet Office, Government of Japan). Martim Brandão is supported by the EPSRC RAIN Hub, grant EP/R026084/1. Finally, we would like to thank N. Sakai for help with the open loop experiments and K. Kumagai for help with initially setting up the temperature experiments.


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  • Wei Xin Tan
    • 1
  • Martim Brandão
    • 1
    • 2
    Email author
  • Kenji Hashimoto
    • 1
    • 3
  • Atsuo Takanishi
    • 1
    • 3
  1. 1.Waseda UniversityTokyoJapan
  2. 2.Oxford Robotics InstituteUniversity of OxfordOxfordUK
  3. 3.Humanoid Robotics InstituteWaseda UniversityTokyoJapan

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