Fig. 1

The external forces and torques in (a) are solely responsible for the centroidal momentum rate change in (b). (c): Linear momentum rate change \(\dot { \boldsymbol {l}}\) has a one-to-one correspondence with the GRF f. (d): The centroidal angular momentum rate change \(\dot { \boldsymbol {k}}\) is determined by both f and CoP location p. (e): Conversely, p is determined by both \(\dot { \boldsymbol {l}}\) and \(\dot { \boldsymbol {k}}\)