Fig. 1From: Assessment of the underlying systems involved in standing balance: the additional value of electromyography in system identification and parameter estimationExperimental set up. a The Bilateral Ankle Perturbator (BAP) was used to apply the support surface (SS) rotations. b The actual SS rotation, body sway (BS) and ankle torque (T) were measured in combination with the muscle activation (MA). c A typical example of human reactions on the SS rotation. Time series are presented by mean and standard deviation averaged over data blocksBack to article page