Series Elastic Actuators for legged robots

@inproceedings{Pratt2004SeriesEA,
  title={Series Elastic Actuators for legged robots},
  author={Jerry E. Pratt and Benjamin T. Krupp},
  booktitle={SPIE Defense + Commercial Sensing},
  year={2004}
}
Series Elastic Actuators provide many benefits in force control of robots in unconstrained environments. These benefits include high force fidelity, extremely low impedance, low friction, and good force control bandwidth. Series Elastic Actuators employ a novel mechanical design architecture which goes against the common machine design principal of "stiffer is better." A compliant element is placed between the gear train and driven load to intentionally reduce the stiffness of the actuator. A… 
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