Phase control for a legged microrobot operating at resonance

@article{Doshi2017PhaseCF,
  title={Phase control for a legged microrobot operating at resonance},
  author={Neel Doshi and Kaushik Jayaram and Ben Goldberg and Robert J. Wood},
  journal={2017 IEEE International Conference on Robotics and Automation (ICRA)},
  year={2017},
  pages={5969-5975}
}
We present an off-board phase estimator and controller for leg position near the resonance of the Harvard Ambulatory MicroRobot's (HAMR) two degree-of-freedom transmission. This control system is a first step towards leveraging the significant increase in stride length at transmission resonance for faster and more efficient locomotion. We experimentally characterize HAMR's transmission and determine that actuator phase is a sufficient proxy for leg phase across the range of useful operating… 
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