*3.4. Data Preparation*

Classification performances were tested after two di fferent approaches for feeding the classifier: giving only knee-angle signal (knee approach) or giving knee-angle and sEMG signals (KEMG approach) as input to train the classifier.

**Figure 2.** Example of normalized flexion-extension knee angle in sagittal plane measured in all the strides walked by a representative subject (red curves). Mean curve is depicted in white. Stance and swing durations are portrayed in green.
