Figure 3

The training of the MLPs. The surface EMG features were the inputs to the MLPs, which used one of the joint angles as training target. The joint angles were obtained from the intact side (amputee subjects), or non-dominant side (intact-limbed subjects). When the EMG from the same side as kinematics was used for training, it was called ipsi-lateral training. When the EMG from the opposite side was used for training, it was called contra-lateral training. α₁, α₂, and α₃ are the joint angles of the three DoFs, as defined Eq. (1), Eq. (2), and Eq. (3), respectively.$\overline{{\alpha }_i}$ are the respectively estimates.