Research‎ > ‎Seminars‎ > ‎Seminars 2009‎ > ‎

11.11.2009 - BIRS: Noise, Time Delay and Balance Control

Ian Loram vs Ramesh Balasubramaniam
  • Passive versus active control of human balance
    • Passive control
      • passive joint meta-stabilization
        • Pin-joint model is not good for getting things to stand up
        • Joints conform during upright position.
      • muscle activity in standing balance
        • Muscles that appear to be on:
          • Soleus
          • Gastrocnemius
          • Ilipsoas
        • How much muscle activity is hidden from "sensing"?
          • VO2 = 20 W delta between standing and lying, 200 W delta between walking and standing
      • short range joint stiffness
        • Stiffness is high for small movements
        • Stiffness is low for large movements
      • control by intermittent activity
      • information flow in passive muscles
      • standing without passive mechanisms
    • Active control
      • The organization of task-specific solutions
        • PCA to determine dimensionality
        • UCM to separate task relevant vs task irrelevant
      • Does the cns understand physics?
      • Intermittency and prediction - Do they exist?
Manoj Srinivasan
  • Optimal control can predict "forward leaning" based on asymmetric "muscles" doing co-contraction.
Jason Kutch
  • Listening to actuators gives you information into how they act.
    • Signal dependent noise gives you information from the endpoint source about the muscles producing the force.
  • Spike-triggered averaging
    • the average stimulus preceding a spike