• Corpus ID: 208548400

Safe rendering of high impedance on a series-elastic actuator with disturbance observer-based torque control

  title={Safe rendering of high impedance on a series-elastic actuator with disturbance observer-based torque control},
  author={Kevin Haninger and Abner Asignacion and Sehoon Oh},
An important performance metric for series-elastic actuators is the range of impedance which they can safely render. Advanced torque control, using techniques such as the disturbance observer, improve torque tracking bandwidth and accuracy, but their impact on safe impedance range is not established. However, to define a safe impedance range requires a practical coupled stability condition. Here, passivity-based conditions are proposed for two variants of DOB torque control, and validated… 

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