FFNN	feed-forward neural network
HF	Hampel filter
HML	Human Motion Laboratory
LS	least squares
M3S	moving three sigma
mocap	MOtion CAPture
MSE	mean square error
NARX-NN	nonlinear autoregressive exogenous neural network
NN	neural network
PJAIT	Polish–Japanese Academy of Information Technology
RMSE	root mean squared error